Sunday 6 October 2024

Rule of Thumb in Polymer Engineering: How Economy of Scale Can Lower Costs

 Hello and welcome to this new Rule of Thumb post. More Rule of Thumbs can be found in my section "Start here"

Economy of Scale: A Brief Explanation

Economy of scale refers to the cost advantage that arises when a company increases its production level. In simpler terms, the more a company produces, the lower the cost per unit becomes. This is because fixed costs (like rent, machinery, and salaries) are spread out over a larger number of units.

How Economy of Scale Can Lower Costs

  • Increased Production Efficiency: Larger production runs often lead to more efficient processes, reducing waste and improving productivity (each time the cumulative production of a given product gets doubled, costs can be reduced in range of 15%).
  • Bargaining Power with Suppliers: Larger companies can negotiate better deals with suppliers due to their increased purchasing volume.
  • Specialized Equipment: Investing in specialized equipment can significantly reduce production costs for large-scale operations.
  • Risk Diversification: Larger companies can better absorb market fluctuations and other risks.
Example: Plastic Injection Moulding

In plastic injection molding, economy of scale is a significant factor in determining production costs. A company that produces a large number of plastic parts can benefit from:

  • Specialized Moulding Machines: High-volume production justifies the investment in advanced, efficient moulding machines that can produce parts faster and with less waste.
  • Optimized Production Processes: With experience and scale, companies can fine-tune their production processes to minimize setup time, reduce cycle times, and improve quality. Using a Lang-factor of 0.75 we can reach a cost reduction of 30% when doubling the production amount (Figure 1).  
  • Bulk Material Purchasing: Larger quantities of plastic resin can often be purchased at a discounted rate, reducing material costs.
  • Efficient Manufacturing Layout: A well-designed manufacturing layout can streamline production flow, minimizing material handling and reducing overhead costs.
Figure 1: xample economy of scale in plastic injection moulding - doubling the production amount leads to a 30% cost reduction. 


By leveraging economy of scale, plastic injection moulding companies can significantly lower their production costs, making their products more competitive in the marketplace. 

Thanks for reading and #findoutaboutplastics

Greetings

Herwig Juster
Literature:
[1] https://www.stratxsimulations.com/latest_materials_circular_markstrat/NetHelp/enu/Handbook-SM-B2C-DG/DocToHelpOutput/NetHelp/index.html#!Documents/productivitygains.htm
[2] https://www.voestalpine.com/highperformancemetals/en/blogposts/how-to-increase-efficiency-and-productivity-in-plastic-injection-molding/#


Friday 4 October 2024

Polymer Selection Funnel Example - Smartphone Front Bezel (Consumer Electronics Material Selection)

Hello and welcome to another polymer material selection example for which we use the POMS-Funnel Method (in detail explained here and in this video). Today’s mission is to select the optimal polymer for Liquid Crystal Display (LCD) bezel used in smartphones. 

Figure 1 presents the four different stages of the material selection funnel as well as the tools we can use to facilitate the selection. We can use this as a guideline throughout the selection journey. 

Figure 1: Polymer Selection Funnel - overview of the four different funnel stages and tools.

POMS-Funnel Method: 

Funnel stage 1: Material selection factors

In the first Funnel stage we focus on gathering and understanding all the requirements of the LCD bezel for smartphones (Figure 2).  
Figure 2: Overview of a LCD front bezel used in the iPhone 14 Plus. Aim of the first funnel step is to lay out the requirements.


Covering effectively the product requirements, a combination of functionality questions and selection factor questions can support you to achieve this. First we have to ask some questions on the functionality of the part. 

Following questions can help us with this assessment:
-What are the performance requirements (structural, etc.)?
-Do you want to combine multiple parts or functions?
-What will be the structural load of the part (static, dynamic, cycling, impact, etc.)?
-What will be the environmental impact on the part (chemical, temperature, time)?
-What is the expected lifetime of the product?

After answering the functionality questions, we continue with the, in my point of view,  six essential questions on material selection factors (6 What's).

A more detailed list can be found here (incl. download): Material Selection Requirements Checklist

1. What is the service environment of your part?
2. What are the regulatory requirements?
3. What types of load at which service temperature and time need to be fulfilled?
4. What other things such as wear and friction, electrical properties such as CTI, electrical breakdown strength, aesthetics and colour (relevant for application with food contact, and toys), and more, need to be considered?
5. What is the processing and fabrication method?
6. What are the economic and commercial considerations?

In general, LCD bezels, the outer frame that surrounds the LCD screen in smartphones, play a crucial role in both aesthetics and functionality. The materials used for these bezels must meet specific requirements to ensure optimal performance and durability.

Key Requirements for LCD Bezel Materials:

Aesthetics:
-Color: The bezel's color should complement the overall design of the smartphone and align with current trends.
-Finish: The finish can range from matte to glossy, depending on the desired aesthetic.
Texture: The texture can be smooth, textured, or even embossed to create a unique feel.

Durability:
-Scratch Resistance: The material should be resistant to scratches, as smartphones are often carried in pockets or bags and may come into contact with other objects.
-Impact Resistance: The bezel should be able to withstand minor impacts without cracking or shattering.
-Strength: Thin wall frame need to have high strength levels too, together with dimensional stability.
-Wear and Tear: The material should be durable enough to resist wear and tear over time.

Functionality:
-Signal Transmission: The bezel material should not interfere with wireless signal transmission, such as Wi-Fi or cellular data. The material should have a dielectric constant of 3.5.
-Display Visibility: The bezel should not obstruct the viewing angle of the LCD screen.
-Thermal Conductivity: The material should have good thermal conductivity to help dissipate heat generated by the smartphone's internal components.
-Processability: High flow material enabling to fill thin wall thickness; possibility for  IML/IMD “In-Mold Labelling/Decoration”,

Cost:
-Affordability: The material should be cost-effective to ensure that the smartphone remains competitive in the market.

Capturing all requirements and project details can be done by using the requirement worksheet and Table 1 shows the outcome. 
Table 1: Overview of requirements for the LCD front bezel using the requirement worksheet. 

Funnel stage 2: Decision on thermoplastic or thermoset

With the LCD bezel requirements, together with the understanding of the differences of thermoplastics (amorphous and semi-crystalline) and thermosets we can screen the databases and material suppliers for suitable material candidates.  

There are reliable database such as Campus and Omnexus and I created dashboards to support this step too: 



All dashboards can be found also here.

Deciding between the thermoplastic or thermoset route is the first step. In our case, thermoplastics offer many advantages for this application, especially impact performance at low and high temperatures and injection moulding in the range of million parts per year in an economical way. Reviewing the bezel requirements, both amorphous and semi-crystalline materials are feasible. 

After the material screening, I pre-selected the following materials (Table 2): 
  • Lexan® HFD4472 (PC-CoPo-GF20)
  • Kalix 2545 (PA 6.10-GF45; bio-sourced)
  • TORAYCON™ 7151G-F03 (PBT+SAN-GF30)
  • Zytel® HTN52G35HSL (PPA-GF35; PA6T/66-GF35)
Table 2: Overview preselected grades and their commercial suppliers.

Funnel stage 3: Selection discussion with worksheet (qualitative matrix analysis)

The third funnel stage represents a core element in the whole material selection funnel. It is a detailed selection discussion with a worksheet. I call it the decision matrix analysis and it ranks all of the pre-selected polymers. The decision matrix analysis consists of five steps. The base calculation principle is a scoring of each of the pre-selected materials for each of the material selection factors. In the end we add up all weighted scores for each material. The materials with the highest score are most suitable for selection and further investigation in the fourth stage.

How to start the qualitative matrix analysis?
I developed an online tool in order to facilitate this step here (Polymer Material Selector V1.1). As an alternative, you can reach out to me and I will provide you with an excel version of it. I only considered the must-have requirements.

In Table 3 the outcome of the qualitative matrix analysis is shown. PA 6.10-GF45 scored the highest number of points (score: 132 points), followed by PC-CoPo-GF20 (score: 98 points) and PBT+SAN-GF30 (score: 97 points) and PPA-GF35 (score: 93). All four materials should be validated in the Funnel stage 4 since there are important tests such as the antenna performance tests, falling and rolling test, and anti-stain test. 

Table 3: Results of the qualitative matrix analysis.

Funnel stage 4: Testing, selection of material and vendor

In the final step of the POMS-method we perform the antenna performance tests, falling and rolling test, and anti-stain test, as well as build first prototypes (with the support of CAE - filling simulation). Once all the test results are available, the final material decision can be done. 

For the premium consumer segment of smartphones, PA6.10-GF45 and PC-CoPo-GF20 are a good choice and if surface aspects are not the most important criteria, the remaining two materials (PPA and PBT+SAN) can be considered too. 

Conclusions
In this example we applied the POMS-method  for selecting the optimal thermoplastic grade for a LCD bezel used in smartphones. It is a systematic approach with a resin-agnostic view allowing to consider different material choices and document them for a later review and optimization. 

More polymer material selection examples using the funnel approach can be found here:

Thanks for reading and #findoutaboutplastics

Greetings

Herwig Juster
Literature:
1] https://www.sunsky-online.com/de/p/EDA006095301/For-iPhone-15-Plus-Front-LCD-Screen-Bezel-Frame.htm
[2] https://www.polymerio.com/tds-pds/pbt-compound-toray-toraycon-7151g-f03-b--tds-pds
[3] https://materials.celanese.com/de/products/datasheet/SI/Zytel%20HTN52G35HSL%20BK083
[4] https://www.syensqo.com/en/brands/kalix-hppa
[5] https://www.sabic.com/en/products/specialties/lnp-compounds-and-pc-copolymer-resins/lexan-copolymer
[6] https://www.plastics.toray/de/products/toraycon/pbt_003.html











Wednesday 11 September 2024

Plastic Part Marking Codes: ISO 11469 vs. ISO 16396

Hello and welcome to a new blog post. Today we discuss the differences between ISO 11469 and ISO 16396 used for plastics identification as well as for part marking and how each of them is used in the plastics industry.

Check out this post which provides you with an overview on the major part marking codes  and standards (incl. miniguide for downloading).

Download the miniguide here.

Why Plastic Part Marking Codes?

Identification of plastics products is easier with a part marking system. This allows for better decision making for:

  • handling plastic products,
  • better waste recovery
  • more efficient disposal.

Plastic identification and part marking with ISO 11469

ISO 11469:2016 defines a system of uniform marking of products which were made from plastics materials and it references the following standards since they are indispensable for its application: 

  • ISO 472, Plastics — Vocabulary
  • ISO 1043-1, Plastics — Symbols and abbreviated terms — Part 1: Basic polymers and their special characteristics
  • ISO 1043-2, Plastics — Symbols and abbreviated terms — Part 2: Fillers and reinforcing materials
  • ISO 1043-3, Plastics — Symbols and abbreviated terms — Part 3: Plasticizers
  • ISO 1043-4, Plastics — Symbols and abbreviated terms — Part 4: Flame retardants

Example for marking according ISO 11469: acrylonitrile-butadiene-styrene polymer “>ABS<”

ISO 16396-1:2022: Polyamide moulding and extrusion materials

On the other hand we have the ISO 16396 which was introduced particularly for Polyamides used in injection moulding and extrusion (PA 6, PA 66, PA 69, PA 610, PA 612, PA 11, PA 12, PA MXD6, PA 46, PA 1212, PA 4T, PA 6T and PA 9T and copolyamides of various compositions for moulding and extrusion).

The designation consists out of five data blocks:

-Data block 1: identification of the plastic by its abbreviated term (PA), and information about the chemical structure and composition

-Data block 2: position 1: Intended application and/or method of processing; positions 2 to 8: Important properties, additives and supplementary information

-Data block 3: designatory properties

-Data block 4: fillers or reinforcing materials and their nominal content

-Data block 5: contains additional information which may be added if needed

Example: PA6T/66 MH, 14-190, GF50

  • PA6T/66: Polyamide 6T which is a homopolymer based on terephthalic acid and Polyamide 66 which is based on hexamethylenediamine and adipic acid. 
  • M: injection moulding; 
  • H: heat ageing stabilized
  • 14: viscosity number (in ml/g) > 130 but below 150; 
  • 190: tensile modulus of elasticity between 17000 MPa and 20000 MPa
  • GF50: wt% 50 glass fiber reinforcement

Below you find a YouTube shorts on this topic too. 

Thanks for reading/watching and #findoutaboutplastics

Greetings

Herwig Juster

[1] https://www.iso.org/obp/ui/en/#iso:std:iso:11469:ed-3:v1:en

[2] https://www.findoutaboutplastics.com/2020/12/plastic-part-marking-overview-codes-and.html


Sunday 8 September 2024

High Performance Thermoplastic Selection - Polysulfides (Polyphenylene sulfide - PPS), Polysulfones (PSU, PESU, PPSU), and Polyarylates (PAR) [Part 2A]

Hello and welcome to the second part of our High Performance Thermoplastics selection blog series. The second part will focus on the introduction of high performance polymers, their chemistry and production processes, their main properties, their processing methods, and last but not least, applications.

Here you can jump to Part 1.

There are six major high performance thermoplastics families (“the magnificent six”) which we will discuss: 

-Part 2A: Polysulfides (Polyphenylene sulfide - PPS), Polysulfones (PSU, PESU, PPSU), and Polyarylates (PAR)

-Part 2B: Imide-Based Polymers (PEI, PAI, PESI, TPI, PI) and Polybenzimidazoles (PBI, PBI+PEEK, PBI+PEKK)

-Part 2C: Polyether (PPE, PAEK, PEEK, PEKK)

-Part 2D: Liquid Crystal Polymers (LCP)

-Part 2E: Semi- and Fully Aromatic Polyamides (PARA, PPA, Aramid)

-Part 2F: Polyhalogenolefins (PTFE, PCTFE, FEP, PVDF, ECTFE)

All thermoplastics can be visualized by using the performance pyramid, as shown in Figure 1. Based on production volumes, performance, and price, thermoplastics can be categorized as commodity plastics such as Polyolefins, engineering plastics such as Polyamide, and high performance polymers. Polysulfides (PPS), Polysulfones (PSU, PESU, PPSU), and Polyarylates (PAR) are highlighted since they will be discussed in this post.

Figure 1: Plastics Performance Pyramid highlighting PPS, Polysulfones, and PAR. 

Polysulfides (Polyphenylene sulfide - PPS), Polysulfones (PSU, PESU, PPSU), and Polyarylates (PAR)

The first major family we discuss is the Polysulfide family which contains Polyphenylene sulfide (PPS), followed by Polysulfones (PSU, PESU, PPSU), and Polyarylates (PAR). Polyphenylene ether (PPE) can be added to this family too, however I placed it in the family of Polyethers together with Polyetheretherketone (PEEK). 

Polyphenylene sulfide (PPS) - The polymer that thinks it’s metal…

Everyone who had already a part made out of PPS in his hand and let it drop will immediately recognize its metal-like sound. Thus, sometimes PPS is referred to as the “polymer that thinks it’s metal”. 

Chemistry and Production

PPS is a semi-crystalline polymer and its backbone consists of aromatic rings (phenylene groups) linked by sulfide bridges. This unique structure grants PPS its remarkable properties. The production process typically involves step-growth polymerization, where para-dichlorobenzene reacts with sodium sulfide under specific conditions in a solvent like N-methylpyrrolidone (NMP). However, numerous modifications and post-treatments can be employed to create specific PPS grades with tailored properties. There are two main routes making PPS and depending which route was taken, a so-called cured PPS (“flash PPS”, referring to the flash evaporation of water and solvent at the end of the two-step process; first step: sodium hydroxide reacts with solvent N-Methyl-2-pyrrolidone (NMP); step two: hydrogen sulfide gas introduced and a suspension is the result; curing by air is needed to increase the molecular weight; it leads to chain elongation and branching; typical MW before curing: 18,000 – 22,000 and after: 45,000) or linear PPS (“quench PPS”, where the reaction takes place in a solvent and it is continuous without having to remove water; "quench" or "quenching" = process of rapidly heating and mixing the slurry from the reactor with a quench medium, usually water and/or steam, leading to polymerization determination). The flash process has a higher yield efficiency (>92 %), good operational stability with better quality control. The quench process results in higher MW directly ( MW ~50,000) and lower yield efficiency (~88%).

Cured (“branched”) PPS has a dark brown color and in the beginning, linear PPS grades showed superior toughness, less off-gasing, lower flash appearance, and improved weldline strength. Parts ade out of cured PPS show an improved dimensional stability and creep performance. However, over time and with production improvements, differences were minimized.  

Well-known trade names for PPS include Ryton® (Syensqo), Torelina® (Toray), Fortron® (Celanese), Durafide® (Polyplastics), Xytron® (Envalior) and DIC PPS (DIC).

Properties of PPS

  • High-temperature performance: PPS boasts a melting point around 280°C (536°F) and can withstand continuous use (UL 746B) at temperatures exceeding 200°C (424°F). This makes it ideal for applications that encounter extreme heat.
  • Chemical resistance: PPS exhibits exceptional resistance to a wide range of chemicals, including strong acids, bases, and solvents. This allows it to function in harsh chemical environments. Concentrated nitric acid is one of the few chemicals which can dissolve PPS, apart from that there are no other chemicals which can dissolve PPS at a temperature below 200°C. 
  • Dimensional stability: PPS maintains its shape remarkably well at elevated temperatures, minimizing warping or shrinkage. For medium sized parts, 0.1% of its given dimension can be held and for large parts, 0.2% of the set dimension can be held.
  • Flame retardant: PPS is inherently flame retardant and self-extinguishing, making it a safe choice for applications requiring fire resistance. It can achieve the UL94 V0 at 0.75 mm and has a limiting oxygen index (LOI) which is estimated according to ISO 4589, of 45%.
  • Electrical insulator: The non-polar structure of PPS makes it a good electrical insulator. 
  • Excellent flow properties: allowing to fill thin wall thicknesses. Amount of crystallization is around 50%. 

Table 1 summarizes selected mechanical properties of non reinforced PPS, cured PPS, and linear PPS moulding compounds. Often questions around the part marking code for highly filled PPS compounds arise. According to ISO 11469, the 65 wt% PPS compound R-7-120NA has following part marking code, which is in line with the VDA 260 too: >PPS-(GF+MD)65<.

Table 1: Selected mechanical properties of non reinforced PPS, cured PPS, and linear PPS moulding compounds [1].

Processing Methods

PPS can be processed using various techniques:

  • Injection Moulding: This is the most common method for shaping PPS into complex parts. Mould temperatures of minimum 135°C are needed to have a proper crystallization of the polymer. 
  • Extrusion: PPS can be extruded into sheets, rods, tubes, and pipes for diverse applications.
  • Machining:  PPS exhibits good machinability, allowing for the creation of precise components.
  • Coating: PPS powders can be used to coat metal sureafce such as kitchen pans. 

Applications of PPS

Due to its exceptional properties, PPS finds applications in a variety of industries:

  • Automotive:  PPS is used for pump components, engine parts close to the combustion engine, and electrical connectors due to its heat and chemical resistance. Also for e-mobility, PPS plays a key role, especially for high temperature electronics. Currently, a typical internal combustion engine (ICE) has around 700 grams of PPS polymer on board. New numbers form Asia reveal that there will be 3 to 4 kg of PPS in electric vehicles (EVs) and hybrid electric vehicles (HEVs).
  • Chemical Processing: PPS is ideal for pipes, valves, and pump housings due to its excellent chemical resistance.
  • Electrical & Electronics: PPS is a valuable material for connectors, circuit boards, and other electrical components because of its electrical insulating properties.
  • Aerospace: PPS finds use in aircraft components due to its lightweight nature and high-temperature performance.

Economic Aspects

PPS is a high-performance polymer, and its production costs are typically higher than those of some commodity plastics. However, PPS prices are still much lower compared to other high performance polymers such as PEEK. PPS and its exceptional properties often translate into longer lifespans, reduced maintenance needs, and improved performance, justifying the initial investment.

PPS stands out as a versatile and high-performance thermoplastic. Its unique combination of properties makes it a valuable material for demanding applications across various industries. As polymer engineering continues to evolve, PPS is certain to remain a key player for years to come.


Polysulfones (PSU, PESU, PPSU) - Take me to the moon

Polysulfones (PSFs) are an amorphous class of high-performance thermoplastics renowned for their exceptional properties, including heat resistance, chemical resistance, and dimensional stability. These attributes make them ideal for applications requiring materials that can withstand harsh conditions and maintain their integrity over time. Polysulfone was used as an external sun protection helmet visor for the Apollo 11 crew which landed on the moon on  July 20th 1969. 

Chemistry and Production

The chemical structure of polysulfones is characterized by a repeating ether sulfone unit (-O-SO2-). This unique structure contributes to the material's excellent properties.

Polysulfones are typically produced through a nucleophilic aromatic substitution reaction between bisphenol A and a dichlorosulfone. The reaction is carried out in a polar aprotic solvent, such as dimethyl sulfoxide (DMSO), in the presence of a base.

Main Properties

  • Heat resistance: Polysulfones have a glass transition between 190°C (374 °F) for PSU and 220°C (428 °F) for PESU and PPSU, leading to a  high heat deflection temperature, making them suitable for applications in hot environments.
  • Chemical resistance: They are resistant to a wide range of chemicals, including acids, bases, and solvents.
  • Dimensional stability: Polysulfones exhibit excellent dimensional stability, maintaining their shape and size even under varying conditions.
  • Flame retardancy: Many polysulfone grades are inherently flame-retardant and fulfil the UL94 V0.
  • Hydrolytic stability: They are resistant to hydrolysis, making them suitable for applications in contact with water. PSU and PPSU polymers exhibit excellent resistance to hydrolysis, remaining stable under high-temperature steam and water exposure. This characteristic makes them suitable for medical instruments requiring repeated autoclaving. For example, PSU performs well even after 100 autoclave cycles at 134°C. PPSU on the other hand, maintains its original physical properties like rigidity and ductility up to 1000 cycles at the same temperature.
  • Biocompatibility: There are polysulfone (PSU) and polyphenylene sulfone (PPSU) grades which have been developed for usage in medical devices that require long-term biocompatibility. For example, there are PSU and PPSU grades such as Syensqo's Eviva PSU and Veriva PPSU grades which are biocompatible polymers developed for long-term medical implants. They meet regulatory standards for devices in contact with bodily tissue/fluids for 30+ days and are manufactured following ISO 13485 and cGMP guidelines. In addition, standard grades of polysulfone and PPSU are used in medical devices that are in contact with bodily fluids and tissue short-term, or less than 24 hours.

Differences between polysulfone (PSU), polyethersulfone (PESU) and polyphenylene sulfone (PPSU)

While all three materials - polysulfone (PSU), polyethersulfone (PESU), and polyphenylene sulfone (PPSU) - are high-performance thermoplastics with similar properties, there are some key differences between them.

  • Polysulfone (PSU): The repeating unit in PSU is a bisphenol A sulfone. PSU offers good heat resistance, chemical resistance, and dimensional stability.
  • Polyethersulfone (PESU): PESU has a repeating unit of bisphenol S ether sulfone. It exhibits excellent heat resistance, hydrolytic stability, and chemical resistance, making it suitable for applications in harsh environments.
  • Polyphenylene Sulfone (PPSU): PPSU has a repeating unit of biphenyl sulfone. It offers exceptional heat resistance, mechanical strength, and flame retardancy. It has the highest stress crack resistance and notched impact strength of all three types of Polysulfones. 

Table 2 compares the different properties of PSU, PESU, and PPSU to each other. 

Table 2: Comparison of the the different properties of PSU, PESU, and PPSU.

Processing Methods
Polysulfones can be processed using various methods, including:
  • Injection molding: This is the most common method for producing polysulfone parts.
  • Extrusion: Polysulfones can be extruded into sheets, films, and profiles.
  • Blow molding: This process is used to produce hollow objects from polysulfone.
  • Thermoforming: Polysulfones can be thermoformed into complex shapes.

Applications
  • PSU: Automotive components, electronics, medical devices, and food processing equipment.
  • PESU: Medical devices, electronics, water filtration, and chemical processing.
  • PPSU: Aerospace components, electronics, medical devices, and high-temperature applications.
Trade Names and Economic Aspects
There are a hand full of  major chemical companies which produce polysulfones, including:
  • BASF: Ultrason® E PESU; Ultrason® P PSU; Ultrason® S PPSU;
  • Syensqo: Udel® (PSU), Veradel® (PESU), Radel® (PPSU)
  • Sumitomo Chemical: Sumikaexcel® PESU
The market for polysulfones is expected to continue to grow due to their versatility and performance advantages. However, the high cost of polysulfones compared to other engineering thermoplastics can limit their use in some applications. For lower end applications it is competing against Polycarbonate (PC) and in the high-performance segment with Polyetherimide (PEI). 

Polysulfones are a valuable class of high performance thermoplastics with a wide range of applications. Their exceptional properties, including heat resistance, chemical resistance, and dimensional stability, make them ideal for demanding environments. As the demand for high-performance materials continues to grow, the use of polysulfones is expected to increase in the coming years.


Polyarylates (PARs) - UV protection with excellent retention of optical properties, combined with high temperature resistance

Polyarylates (PARs) is an aromatic polyester derived from aromatic dicarboxylic acids and bisphenols. They possess a combination of excellent properties, including high heat resistance, chemical resistance, and mechanical strength, making them suitable for a wide range of applications.

Chemistry and Production
The synthesis of polyarylates typically involves a condensation polymerization reaction between aromatic dicarboxylic acids and bisphenols. The most common monomers used are terephthalic acid (TPA) and bisphenol A (BPA) or bisphenol S (BPS). However, other monomers can be used to tailor the properties of the resulting polymer.

The reaction is typically carried out in a melt polymerization process, where the monomers are heated in the presence of a catalyst. The reaction proceeds by forming ester linkages between the carboxylic acid and phenolic groups. Based on the used monomers we can distingish between Type 1 and Type 2 PAR. 

Type 1 vs. Type 2 Polyarylates: A Key Distinction
Polyarylates can be broadly categorized into two types based on their chemical structure and properties: Type 1 and Type 2 (Table 3).

Type 1 Polyarylates
  • Structure: Typically composed of only aromatic hydroxycarboxylic acid. Most common Type 1 PAR is the Poly-4-hydroxybenzoate (PHB) which consists of aromatic rings linked by ester groups.
  • Properties: Known for their excellent heat resistance, dimensional stability, and chemical resistance. They often exhibit a balance of properties, making them suitable for a wide range of applications.

Type 2 Polyarylates
  • Structure: Typically composed of terephthalic acid (TPA) and bisphenol A (BPA) or other aromatic dicarboxylic acids or bisphenols, such as isophthalic acid or bisphenol S. Most common Type 2 is the Polybisphenol-A terephthalate (PBAT).
  • Properties: May exhibit enhanced properties in specific areas, such as higher toughness, lower water absorption, or improved flame retardancy. The choice of monomers can be tailored to meet specific application requirements.
Table 3: Structure and property comparison of Type 1 and Type 2 PAR. 


Main Properties
Polyarylates exhibit a number of desirable properties, including:
  • High heat resistance: They have excellent thermal stability, allowing them to be used in high-temperature applications. BPAT has a Tg of 196°C (384.8 F), allowing for a short term usage up to 170°C. The heat deflection temperature (1.8 MPa) of BPAT is 174°C (345.2 F) and 40°C higher compared to PC (Tg=148°C; HDT = 135°C). 
  • Chemical resistance: They are resistant to a wide range of chemicals, including acids, bases, and solvents. They are especially resistant towards oils and alcohols when blended with PET, still keeping their transparency. Resistance towards alkali, ketones, and aromatic hydrocarbons is slow.   Also, neat PAR resins are more sensitive to stress cracking. 
  • UV stability: The UV-stability of PARs is high, since UV radiation causes the formation of a protective layer which in turn serves as UV protection. PARs are able to prevent the passage of ultraviolet light at and below 350 nm and transmit almost 90% light at a wavelength of 400 nm or more. It could be shown in various 8,000-hour long-term tests that PAR, in contrast to PS and PC, retains its almost untarnished shine even under the influence of UV. 
    • Why is there such a high ultraviolet absorption capacity and high weathering durability? PAR absorbs UV energy and causes a so-called Fries rearrangement reaction. This reaction produces a benzophenone structure on the resin surface. As a consequence, PAR is able to block light of 400 nm or less. The tone of color (yellowing) changes of PAR too due to the Fries rearrangement.
  • Mechanical strength: They have good mechanical properties, including high tensile strength, flexural strength, and impact resistance. In general, they can be placed between Polycarbonate and Polysulfones. Strength and stiffness are better compared to PC. Impact strength is high at lower temperatures (-40°C), however not as high as with PC. Additionally, the elongation at break is not as good as that of PC.
  • Dimensional stability: They exhibit low shrinkage and excellent dimensional stability. PARs have excellent elastic recovery which makes them a suitable material for spring applications. 
  • Electrical properties: They have good electrical properties, such as high dielectric strength and low water absorption.
  • Optical properties: almost as transparent as Polycarbonate and PMMA. PARs have a slight yellow color and transmit almost 90% light.
  • Good for blending with other polymers: 
    • with PET and PETG, to decrease shrinkage and warpage of PET; 
    • with PC and PBT, in order to increase the thermal heat resistance.
    • with PC, PET and PETG, to integrate a permanent UV protection. 

Processing Methods
Polyarylates can be processed using various methods, including:
  • Injection moulding: This is the most common method for processing polyarylates, allowing for the production of complex parts. PARs have a high melt viscosity and processing is harder. As a result, flow enabler such as adding special groups or atoms, mineral filler/glass fiber reinforcement, and alloying with other polymers, resulting PAR/PET, PAR/PA, PAR/ PC is done. Since the structure of PAR is similar to PC, it can be processed by the same injection moulds. 
  • Extrusion: Polyarylates can be extruded into sheets, films, and profiles.
  • Thermoforming: This process involves heating a sheet of polyarylate and forming it into a desired shape.
  • Compression moulding: This method is suitable for producing large, thick-walled parts.

Applications
Polyarylates are used in a wide range of applications, including:
  • Automotive industry: Components such as engine covers, under-hood parts, and interior trim.
  • Electrical and electronics: Connectors, circuit boards, and housings.
  • Medical devices: Surgical instruments, implants, and diagnostic equipment.
  • Aerospace: Structural components and protective coatings.
  • Industrial equipment: Pump housings, valves, and pipes.
Trade Names and Economic Aspects
Following major chemical companies produce polyarylates under various trade names, including:
  • Unitika: U-Polymer®
  • Westlake Plastics: Ardel® (only semi-finished products)
The market for polyarylates is growing at an average of 3% p.a., driven by increasing demand in various industries. The high performance and versatility of polyarylates make them attractive to manufacturers seeking materials with superior properties.

Outlook to Part 2B
In Part 2B we continue with the detailed discussion of Imide-based polymers (PEI, PAI, PESI, TPI, PI) and Polybenzimidazoles (PBI, PBI+PEEK, PBI+PEKK).


Thank you for reading!
Greetings and #findoutaboutplastics
Herwig Juster

Literature:

[1] https://www.syensqo.com/en/brands/ryton-pps

[2] https://www.plastics.toray/products/torelina/

[3] https://www.celanese.com/products/fortron-polyphenylene-sulfide

[4] https://plastics-rubber.basf.com/global/de/performance_polymers/products/ultrason

[5] https://www.syensqo.com/en/brands/radel-ppsu

[6] https://www.unitika.co.jp/plastics/e/products/par/upolymer/

[7] Kaiser - Kunststoffchemie für Ingenieure

[8] https://www.mueller-ahlhorn.com/par-polyarylat-ein-polymer-mit-vielseitigen-eigenschaften/

[9] https://www.genesismedicalplastics.com/what-is-polysulfone/?no_cache=1725462936

[10] https://www.syensqo.com/en/chemical-categories/specialty-polymers/healthcare/implantable-devices

[11] https://m.ky-plastics.com/news/similar-to-pc-but-more-advanced-polymer-poly-49365791.html

[12] https://www.unitika.co.jp/plastics/e/products/par/unifiner/

[13] https://www.unitika.co.jp/plastics/e/products/par/upolymer/p-series/ps-01.html

[14] http://www.enexinternational.com/PPS_Presentation_for_Web.pdf

[15] https://patents.google.com/patent/WO2016099694A1/en

Thursday 5 September 2024

Permanent UV protection of PC, PET and PETG without special additives

Hello and welcome to a new post. Today I answer another community question, this time around how to integrate a permeant UV protection for parts made out PC and PET, as well as PETG without losing the optical appearance over time, together with mechanical properties. 

There are engineering polymers such as Polymethylmethacrylate (PMMA; known by its famous trade name “Plexiglas”) which have very good optical properties (light transmission up to 92%) and a very good inherent weatherability and ageing properties. There are other polymers such as Polycarbonate (PC) and Polyethylene terephthalate (PET) which, when exposed to UV radiation, change their appearance and properties over time. To prevent this, UV stabilizers can be added, however over time they are consumed and loose their effectiveness. Also, optical properties are influenced by adding additives. 

Another approach for having a long-lasting UV protection is by blending PC and PET with Polyarylate (PAR), an amorphous high performance polymer. 

Polyarylates (PARs) are a class of high-performance thermoplastics derived from aromatic dicarboxylic acids and bisphenols. They possess a combination of excellent properties, including high heat resistance, chemical resistance, and mechanical strength, making them suitable for a wide range of applications.

Why? 

The UV-stability of PARs is high, since UV radiation causes the formation of a protective layer which in turn serves as UV protection. It could be shown in various 8,000-hour long-term tests that PAR, in contrast to PS and PC, retains its almost untarnished shine even under the influence of UV. Also, almost as transparent as Polycarbonate and PMMA.

Additional effects of blending PET with PAR is the decrease of shrinkage and warpage, as well as an increase in thermal stability. The later is valid for PC too. 

Check out my new Youtube #shorts on this topic too: 


If you want to learn more about high performance polymers and their "special skills", check out here my high performance thermoplastics selection blog post series I recently started. 

Thanks for reading and watching!

Greetings and #findoutaboutplastics

Herwig 

Literature:

[1] https://www.findoutaboutplastics.com/2023/10/design-properties-for-polymer-engineers.html

[2] https://www.unitika.co.jp/plastics/e/products/par/upolymer/

Monday 19 August 2024

Condensed Comparison of Plastic Piping Materials for Residential Use (HDPE vs PEX-A, PEX-B, and PEX-C)

Hello and welcome to this post on plastic piping materials used for residential building applications, and mainly we will compare HDPE pipes to PEX-A, PEX-B, and PEX-C pipes. 

What are the top 5+ plastics used in building and construction?

Most used plastics in building and construction are polyvinyl chloride (PVC), high density polyethylene (HDPE), expanded polystyrene (EPS), polyurethane (PU), polycarbonate (PC) and polymethyl methacrylate (PMMA). PVC is used for window frames and floorings, HDPE for tubing and piping, EPS and PU for outside and inside insulation. PC and PMMA is used for transparent sheeting applications applied for example at carports. Benefits of using plastics in construction are that they are lightweight, energy efficient, quick and safe installation compared to other materials, cost effective and high resistance to UV and fire. 

A detailed example of a polymer material selection for water plumbing pipes can be found here

Comparison of HDPE and PEX as piping materials

HDPE

  • HDPE stands for High-Density Polyethylene.
  • Characteristics: Highly durable, resistant to chemicals and corrosion, and has a long lifespan.
  • Common Uses: Primarily used for underground drainage and sewer systems due to its strength and resistance to harsh conditions. Less common in residential plumbing for interior applications.

PEX (PEX-A, PEX-B, PEX-C)

PEX is a type of cross-linked polyethylene. The different types (A, B, and C) vary based on the cross-linking process.

PEX-A:

  • Created using a peroxide cross-linking process.
  • Characteristics: Most flexible, resistant to high temperatures and pressures, and has excellent memory recovery.
  • Common Uses: Widely used in residential plumbing for hot and cold water distribution, radiant heating, and snow melting systems.

PEX-B:

  • Created using a silane or moisture process.
  • Characteristics: Good flexibility, balance of cost and performance, and suitable for most residential applications.
  • Common Uses: Popular choice for residential plumbing due to its balance of properties and cost-effectiveness.

PEX-C:

  • Created using an irradiation process.
  • Characteristics:  Less flexible than PEX-A and PEX-B, and offers good resistance to chemicals and high temperatures.
  • Common Uses: Used in selected residential applications, and less common than PEX-A and PEX-B.

Table 1 shows a summary of the key differences between HDPE, PEX-A, PEX-B, and PEX-C piping materials. 

Table 1: Key differences summary of HDPE vs PEX (A, B, and C) as piping materials. 

In conclusion, HDPE as piping material is primarily used for underground applications. PEX-A is the most flexible and performs best in demanding conditions. PEX-B offers a good balance of properties and is a popular choice. PEX-C is less flexible and still suitable for some residential applications.

The optimal piping material choice for your specific project depends on factors such as budget, desired performance, and local building codes.

Watch below a video I made on this topic too: 



Thanks for reading and #findoutaboutplastics

Greetings,

Literature:

[1] https://www.sharkbite.com/us/en/resources/blog/the-differences-between-pex-a-b-and-c#:~:text=This%20is%20the%20most%20common,%2C%20method%20of%20cross%2Dlinking.

[2] https://www.theplasticbottlescompany.com/plastic-types/hdpe-plastic/#:~:text=High%20Density%20Polyethylene%2C%20commonly%20shortened,when%20used%20for%20HDPE%20pipes.

[3] https://insulation-more.co.uk/blogs/the-pipe-duct-lagging-expert/polyethylene-piping-benefits-applications-and-lagging#:~:text=With%20its%20high%20strength%2Dto,systems%2C%20gas%20pipelines%2C%20sewage%20drainage



Sunday 11 August 2024

High Performance Thermoplastic Selection - Introduction to High Performance Polymers (Part 1)

 

High Performance Plastics Selection by Herwig Juster

Hello and welcome to this blog post series on High Performance Thermoplastics selection. 

Improper selection of plastics for the application is the leading cause for plastic part failure and since most parts fail along weld lines or knit lines, optimal mould design including filling and processing of the part are crucial too. 

Furthermore, there are almost 100 generic “families” of plastics and additionally blending, alloying, and modifying with additives results in 1,000 sub-generic plastic types leads to the following crucial question: How should you choose the optimal polymeric material for your part? Especially, when there are high temperatures, high mechanical requirements, as well as high chemical resistance needs for your application are involved, selecting a high performance polymer will be the key to the solution.  

I have chosen a holistic approach to answer the aforementioned questions and therefore structured this post series in five major parts (Figure 1):

1. Introduction to High Performance Polymers

2. Short profile of the "magnificent six" families:

-Polysulfides (Polyphenylene sulfide - PPS), Polysulfones (PSU, PESU, PPSU), and Polyarylates (PAR)

-Imide-Based Polymers (PEI, PAI, PESI, TPI, PI) and Polybenzimidazoles (PBI, PBI+PEEK, PBI+PEKK)

-Polyether (PPE, PAEK, PEEK, PEKK)

-Liquid Crystal Polymers (LCP)

-Semi- and Fully Aromatic Polyamides (PARA, PPA, Aramid)

-Polyhalogenolefins (PTFE, PCTFE, FEP, PVDF, ECTFE)

3. Key properties and design data for selection

4. Polymer Material Selection 4-stage funnel methodology (POMS-Funnel-Method)

5. Examples for Ultra- and high performance polymer selection

Figure 1: content of the high performance thermoplastics selection blog post series. 

Let us start with the introduction to high performance thermoplastics (HPTs). 

Introduction to Ultra- and High Performance Polymers

Definitions and classification of high performance thermoplastics

High performance polymers, also often referred to as high heat polymers, can be defined over the continuous use temperature (CUT) by using the Underwriters Laboratory (UL) Relative Thermal Index (RTI). According to the UL 746B, high heat polymers need to withstand a continuous use temperature of 150°C for 100,000 hours (approx. 11 years), while retaining at least half of the initial properties afterwards. 
Polymers such as PPS and PEEK inherently fulfill this requirement. Conversely, Polyphthalamides (PPA’s) need to be mechanically reinforced and thermal stabilized so that their continuous use temperature can rise from 130°C to 150°C. Most PPA’s have a continuous use temperature between 120°c and 130°C.

Figure 2 shows the continuous use temperature of commodity, engineering and high performance thermoplastics including the 150°C border. 

Figure 2: Continuous Use Temperature (CUT) of thermoplastics with 150°C borderline in red for high heat plastics.

Not only are high performance thermoplastics used for high temperature applications. There are low-temperature applications such as aircraft parts, oil rigs, industrial refrigeration, superconducting magnets, and liquid-helium devices, which are exposed to temperatures down to -270°C. Material selection becomes critical to prevent any part failure at such low service temperatures. At temperatures below -40°C, the choice for plastic materials becomes limited and fluoropolymers such as PTFE can be a solution. Most important property of fluoropolymers at low temperatures is their ductility: when reaching the absolute zero temperature point (-269°C), the ductility of these polymers holds at approximately 1%. All in all, fluoropolymers are a good material choice for static seals at low temperatures.

Although HPTs main purpose is to be used at elevated or low temperatures, they possess many other exploitable useful properties as well. For instance, crystalline polymers such as poly(ether ether ketone) and poly(phenylene sulfide) can be found in several room temperature applications due to their superior environmental resistance, in particular to organic solvents and acid and alkaline media.
Another definition is over the sales price. Due to their unique properties and added value, HPTs experience low-volume sales at a relatively high selling price. When you compare the ratio of sales price of aliphatic Polyamides to that of high heat polymers, this spreads from 1:3 to 1:20. These ratios vary with the markets the polymers are sold for i.e., automotive, aerospace, electrical-electronic and chemical process industries. 

The classification of HPTs into amorphous and semi-crystalline polymers which is also known from commodity and engineering thermoplastics can be done with HPTs as well. Amorphous representatives are polysulfone (PSU), poly (ether sulfone) (PES), polyetherimide (PEI), thermoplastics polyimide (TPI), and poly(amide imide) (PAI). Semi-crystalline representatives are semi-aromatic Polyamide (PARA, PPA), poly (phenylene sulfide) (PPS), high performance polyesters (LCP, PCT),  poly(benzimidazole) (PBI), fluoropolymers (PTFE, PFA/MFA), poly(ether ether ketone) (PEEK), and poly(ether ketone) (PEK). The latter, especially when filled with glass, carbon, and minerals keep useful mechanical properties above their glass transition temperature (Tg). PEEK, for example, has a Tg of 148 °C , however its continuous service temperature is 250 °C. Also, unfilled PAI is the polymer with highest tensile strength up to 260°C continuous use. PBI is the polymer with the highest Tg, 427°C. In addition, it does not burn. Overall, it is used in applications where highest demand in temperatures, harsh chemicals, and plasma environments are necessary, e.g. fire protection clothing. It is possible to cast PBI into a coating, film or membrane.

In terms of worldwide production, 400 million tons plastics were manufactured in 2022 [13], and 0.2% (0.8 million tons) can be related to high performance polymers.

History, manufacturing and first applications

The plastics boom time started back in the 1960s and in this time the movie hit “The Graduate” was launched. Mr. McGuire turned to Benjamin saying:” There's a great future in plastics. Think about it.” 
And he was right. An early representative of high performance polymers was Poly Phenylene Sulfide (PPS), which was a byproduct of the chemical reaction of benzene and sulfur in the presence of aluminium chloride. It was discovered by Friedel and Crafts in 1888. However, in 1963 Edmonds and Hill developed a new way to produce PPS by using dihalogenated aromatics with sodium sulfide in a polar solvent. Industrialization of PPS succeeded in 1972 by using the Edmond and Hill process and Phillips Petroleum marketed it under the name Ryton®. Mr. Plunkette observed the formation of PTFE in 1938 in his laboratories at DuPont and this material, known as Teflon, quickly gained traction. Another example is the synthesis of poly(aryl ether ketones) (PAEK’s) by Johnson from Union Carbide in the late 1960’s. In 1962, DuPont introduced Polyimide (PI), sold under the name Kapton, to the markets and in 1965, Union Carbide launched the full scale production of Polysulfone (PSU), named Udel®. In the same year, the Amoco Chemical Corporation brought Poly Amide Imide (PAI), under the name Torlon®, to the plastics industry. Polyetehersulfone (PESU) followed in 1972 by ICI and 3M. PEEK was commercialised by ICI at their location in Hillhouse, United Kingdom in 1981. Also in 1981, Amoco introduced a PPA, under the brand name Amodel®. In 1982 General Electric Plastics, respectively J. Wirth introduced the polyetherimide (PEI) resin under the trade name Ultem®. One of the first applications of PEI was in head-lamp reflectors for cars. PEI can be easily metallized and has high dimensional stability at higher service temperatures.  A remarkable application of Polysulfone was as sun protection helmet visor (outer visor) in astronauts’ helmets. Their main function was to protect the astronaut from sun exposure and high temperatures. For this, the inner surface of the polysulfone-based visor was also coated with gold for extended sun visor protection capabilities. The gold coating supported the protection against generated heat inside the helmet as well.

Base production principle for all the high performance thermoplastics mentioned before is the nucleophilic polycondensation, which is a chemical reaction between two functional groups and loosing low-molecular weight by-products such as water and alcohols. Important is to use high-purity monomers (>99%) in order to achieve high molecular mass polymers. Production of high performance plastics is technically more challenging compared to commodity polymers and therefore, for each polymer a dedicated reactor is needed. Manufacturing of compounds is done in-house for the major part, however chemical companies work together with toll-compounders to expand capacity in a fast way or to provide a local source of the compound. 

Why can high performance handle high heat and harsh chemicals?

For better understanding the fundamental structure- property relationships of high performance polymers, we go back to the basic structure of a polymer such as a Polyethylene (PE). The main backbone consists of carbon-carbon bonds and on the carbons, hydrogens are also bonded. This linear macromolecule has a maximum temperature resistance of ca. 80°C and continuous use temperature of 50°C. PE with its aliphatic structure is prone to chain (unzipping) degradation reactions and therefore additives such as heat stabilizer need to be added. Exchanging the aliphatic elementary by aromatic, resistance to chain degradation can be achieved. Reason that the unzipping process is stopped with aromatic elements is that any free radicals generated are stabilized by the Pi-system of the aromatic ring. 

If we replace the carbon in the main chain with a phenyl group, which is an aromatic cyclic group of atoms with the formula C6H5 we obtain the Polyparaphenylene (PPP) (Figure 3). In general, the Benzene ring will be appearing often in the chemical structure of high performance polymers since it forms the major backbone element. It is a ring of six carbon atoms and it is bonded by alternating single and double bonds, however the double is never clearly localized. This in turn makes it harder to be externally attacked. 

Figure 3: Replacing carbon in the main chain with a phenyl group will result in Polyparaphenylene (PPP).

PPP has a temperature resistance of 500°C and is a linear macromolecule made out of benzene building blocks. Aromatic structures result in high macromolecule stiffness. Aromatics in the backbone are a main driver to obtain high heat and chemical resistance. The detailed look at the structure of benzene reveals that the double bonds are not statically localized, i.e. electrons move along the carbon cyclic structure, which is expressed by the ring in the structural formula. This together with inherent molecular stiffness supports stability at high temperatures and in contact with chemicals. If we alternate benzene rings and amide groups, we will get a polymer called poly para-phenyleneterephthalamide (PPTA) or more common known as Aramid and has a heat resistance of 250°C (decomposition temperature between 430-480°C; peak temperature use up to 400°C). It can be processed to fibers and makes it a perfect material for personal protective equipment for firefighters and armed forces.

7 basic building blocks of high performance thermoplastics

The high thermal resistance of PPP has one major downside, i.e. it makes it unsuitable for all melt-based processing techniques such as injection moulding and extrusion. However, the integration of heteroatoms such as Oxygen, Nitrogen, and Sulfur in a polymeric aromatic-based structure can change this. Following, common chemical groups which are used to make melt-processable high performance polymers are described.

1. Diphenyl ether group (Figure 4): In this case, oxygen is the linkage of two phenyls. Diphenyl ether groups are used for example in Polyaryletherketones (PAEK’s). Also, as Phenyl ether group it is used to make Phenyl ether polymers such as PPE+PS (Noryl®).

Figure 4: Diphenyl ether group.

2. Diphenylsulfone group (Figure 5): Here, sulfur is double-bonded to oxygen as well as bonded to phenyls. Diphenylsulfone groups are the main building block for Polysulfone (PSU), Polyethersulfone (PESU) and Polyphenylsulfone (PPSU).

Figure 5: Diphenylsulfone group.

3. Diphenylketone group (Figure 6): Oxygen is bonded over a double bond to carbon resulting in a carbonyl group. Together with the diphenyl, it forms the ketone group. The ketone group is the second crucial element for obtaining Polyetheretherketones (PEEKs).

Figure 6: Diphenylketone group.

4. Diphenylsulfide group (Figure 7): Here, sulfur is linked to phenyls and forming the sulfide group. It forms the basis of Polyphenylensulfide (PPS).

Figure 7: Diphenylsulfide group.

5. Imide group (Figure 8): It consists out of two acyl groups (R-C=O) bounded to nitrogen. It is the base element of Polyimides (PIs), Polyamideimides (PAIs), and Polyetherimides (PEIs).

Figure 8: Imide group.

6. Terephthalic acid (TPA) and Isophthalic acid (IPA) (Figure 9): It is used as precursor for making Polyethylene terephthalate (PET). It also forms the monomer for Polyphthalamides (PPAs). Two carboxyl groups are attached to a benzene in a 1,4 or 1,3 configuration.

Figure 9: Terephthalic acid (TPA) and Isophthalic acid (IPA).

7. Fluor-carbon group (Figure 10): the fluor-carbon bond is the most stable single bond with 485 kJ/mol bonding energy (in comparison, carbon-carbon bond has 350 kJ/mol). Additionally, the fluor atom is much larger compared to the carbon forming a protecting layer around the carbon-carbon main chain. This explains to the same extent the high chemical and thermal stability of fluoropolymers such as PTFE and PVDF.

Figure 10: Fluor-carbon group.

What is their market size and role within the plastics industry? 

In 2021, globally 390 million tons of plastics were produced and this represents 1 vol% (0.4 wt%) of the 90 billion tons of materials which include ceramics, metals, and many more. 90% of the 390 million tons are commodity plastics (351 million tons) and 9.8 % are engineering plastics (38 million tons). High performance thermoplastics represent around 0.2% (78.000 tons) of the global plastics production. Demand growth of high performance thermoplastics is driven by several industries such as automotive (transformation to e-mobility), semiconductor (ensuring the next generation of chips), air, space, and defence industry, as well as electric and electronics. 

Research & Innovation, sales, and marketing of high performance thermoplastics 

Research and development, together with innovation play a key role in the business of high performance polymers. Growth is driven by presenting new material solutions to the market and therefore, an important part of the budget is dedicated to such activities. 

Basically, there are three major routes the high performance polymer manufacturer are taking to drive innovate material growth forward: 
1. New composition: new base polymer combined with additives to have a new compound
2. Extension of existing product line: using existing base polymers and combine it with new additives to achieve new functions such as thermal conductive or blend to existing base polymers to lower costs or have for example better mechanical properties
3. Synthesis of base monomers and polymers: focus to improve the synthesis of monomers in order to lower costs and improve process technology too. 

There are combinations of the three paths and management can steer depending on which economical cycle we are, to focus on one or the other path. Base for all developments is an in-depth understanding of the end-customer requirements which need to be fulfilled with the material solution. Application development, together with customers can range between 6 months in industries such as mobile devices, three to five years in automotive industry, and up to 10 years in medical and aircraft/aerospace applications due to regulatory fulfilment. 

Sales and marketing of high-performance plastics is technically intensive, especially in the early phases of plastic product development. Specialized sales teams with a focus on the end user market such as  automotive industry, consumer, medical technology are needed. And also, high performance plastics sales teams have a greater technical orientation compared to commodity plastic sales teams. For example, material manufacturers which provide solutions to extend the injection tool life, improve yield and provide support in product development generate more value for the customer than a material manufacturer who provides just a discount on the material. 

Stay tuned for part 2 “Short profile of the "magnificent six" families” where we will start with Polysulfides (PPS, Polysulfones) and Polyarylates.

Thanks for reading and #findoutaboutplastics

Greetings,

Herwig 

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

!NEW! Ultra and High Performance Polymer Selection - new online course coming soon - join the waiting list

Literature: 
[1] https://www.findoutaboutplastics.com/2020/05/the-secret-of-high-performance-polymers.html
[2] https://www.findoutaboutplastics.com/2018/09/high-heat-plastics-hhp-demystified-incl.html
[3] https://www.findoutaboutplastics.com/2020/01/high-performance-polymers-suitable-for.html
[4] Vinny Sastri: Plastics in medical devices
[5] D. Parker, J. Bussink, H. van de Grampel, et al., Polymers, High-Temperature, Ullmann’s Encyclopedia of Industrial Chemistry, DOI: 10.1002/14356007.a21_449.pub3
[6] Raymond B. Seymour and Gerald S. Kirshenbaum: High Performance Polymers: Their Origin and Development
[7] Johannes Karl Fink High Performance Polymers, Second Edition (Plastics Design Library)Jul 1, 2014
[8] http://pbipolymer.com/about/celazole-pbi-advantage/
[9] https://www.findoutaboutplastics.com/2019/07/take-me-to-moon-celebrating-50-years.html
[10] https://www.dupont.com/content/dam/dupont/amer/us/en/safety/public/documents/en/Kevlar_Technical_Guide_0319.pdf
[11] https://plasticseurope.org/knowledge-hub/plastics-the-facts-2022/
[12] Kaiser: Kunststoffchemie für Ingenieure
[13] https://plasticseurope.org/knowledge-hub/plastics-the-fast-facts-2023/