Pivot Search - Rethinking Plastics with Herwig Juster I Interview

Hello and welcome to this interview!

I had the pleasure to discuss with Harrison McVeigh Carroll from Pivot Search why plastics are the solution and not the problem, and show how we enable better sustainably at PlastFormance.

Thanks for watching!

Herwig 

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

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

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

My personal website

Plastic Compounds: 5 Key Considerations for Formulating Optimal Thermoplastic Compounds

Hello and welcome to this blog post. Having worked over one year at a plastic compounding company focusing on highly filled plastics, I would like to share some fruit for thought when formulating thermoplastics compounds. In this post we discuss in my point of view the most important considerations (Figure 1). 

Figure 1: 5 Key Considerations for Formulating Optimal Thermoplastic Compounds

Let us get started with the 5 key considerations: 

1) Gather product requirements

It is important to gather as much information on the end-use application and industry the part will be used. OEMs and Tier-1 suppliers will provide such information. Industries have different standards which need to be fulfilled and may limit the use of certain additives (f.e. Healthcare industry). Also we need to be aware of mechanical loads, temperature exposure (short- and long term), as well as chemical exposure. 

2) Selecting the base polymer

Depending on the requirements and industry the application will be used, selection of the base polymer can start. We can select among a wide range of polymers from commodities such as PP, engineering plastics such as Polyamide, and high performance polymers such as PPS and PEEK. Apart from fulfilling the requirements, it is important to keep the polarity and the pH level of the base polymer in mind since both characteristics influence the filler and additive choice. 

3) Selecting additives

In our plastics additives series we already discussed the differences of fillers, reinforces and additives. Check them out here: Part 1, Part 2, Part 3. 

Adding additives can improve and protect different areas of the base polymer. UV stabilisers prolong the lifetime of the base polymers, together with UV absorber for additional protection. Also, we can add antioxidants and in some cases such as Polyolefins, without the usage of antioxidants proper processing would be not even possible.  Furthermore, we can influence the viscosity, impact strength, friction, thermal conductivity, and provide anti static behaviour.

For formulating it is important to calculate in volume percent. Later when you do compounding we switch to weight percentage since you want to weigh in the different materials. 

4) Selecting reinforcements

Property modification of the base polymer is done by using reinforcements such as glass fiber or other types of fibers. Also, fillers are used to lower the overall costs. Mainly calcium carbonate (chalk), magnesium silicate (talc), mica, and glass beads are used to fulfil this. Filler levels above 80 wt% are possible if you want to increase the density of the compound. 

Barium sulphate is used to achieve a higher density, calcium carbonate is a well-known cost reducer. Increasing the rigidity and heat deflection temperature, as well as thermal conductivity is done by talc. If sound deadening properties are needed, mica is a good option. Reducing frictional properties is done by glass beads. 

5) Compounding your formulation

Now we selected the bases polymers, additive package and filler and/or reinforcements. In the next step we have to combine all components via a twin screw extrusion lab line. Having the material in your hands, first tests such as tensile strength, HDT, density, and impact can be done. This allows you to check where you are standing in terms of desired material requirement achievement. If you are happy with the outcome, it is time to move to a production compounding line which is able to make +1 ton of material per hour. Scaling up a standard material with three to four components may have some challenges in the ramp up, however can be resolved quickly. However, if your lab line compound consists of eight to ten components, scale up on the production line may result in bigger challenges. Furthermore, quality checks need to be done in-line, removing material during the production run, making tensile sample bars and testing them. Then results need to be immediately communicated back and changes applied if needed. On the production line, the optimal processing window including temperature profile along the line needs to be estimated. Heart of the extrusion line is the arrangement of the screws which consists of different elements such as mixing, dispersing and transporting. 

Finally you have your plastic compound as it was planned and the formulation as well as production parameters are frozen. Additionally, a quality check via DSC curve can be done, having a footprint for later occasions. Also, the certificate of analysis is done which is needed to supply the customer, together with the material. 

If you have any questions or want to create your own plastic compound, pl. reach out here to support you and if you need plastic sample material for testing, you can reach out here. 

Thanks and #findoutaboutplastics

Herwig 

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

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

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

My personal website

Literature:

[1] https://encompolymers.com/blog/5-common-types-of-polymer-additives-and-their-benefits/

[2] https://interplasinsights.com/plastic-industry-insights/technical-101-formulating-plastic-compounds/

[3] Roger F. Jones - Strategic management for the plastics industry

Polymer Selection Funnel Example - Radar transparent plastics for Advanced Driver Assistance Systems (Radar and Lidar)

Hello and welcome to another polymer materials selection example using the Polymer Funnel methodology. In this post we discuss the selection of radar transparent plastics for e-mobility applications such as Radar and Lidar. Figure 1 presents the four different stages of the material selection funnel and this overview serves us as a guideline.

Figure 1: Polymer Selection Funnel with its four stages.

Global e-Mobility market 2030

Battery electric vehicles (BEVs) are on the rise in Europe and research found out that in Europe around 16% of all new car sales will be BEVs by 2025. This number has the potential to rise to almost 50% by 2023. Looking at a global level, BEV sales will grow from 12 to 25% in the same time period. 

What are the top 5+ plastics used in the automotive industry?

In the past 40 years plastic materials incrementally found their way into automobiles and will continue to support the e-mobility revolution. Currently, the average global plastic amount used in cars is 100 kg. I made an infographic on this topic which can be found here. 

The top three plastics used in Automotive by volume are PP, PVC, and PU, Followed by engineering polymers such as Polyamides, Polyesters (PBT), POM, ABS, PMMA, and PC. On the high performance side, polymers such as PEEK, PPS, PPA, fluoropolymers and fluorelastomers are used. 

Polymer material selection for radar transparent applications - selecting the optimal plastic material

Apart from the rise of e-mobility, we see a rise in autonomous driving applications in cars to improve safety and in the long run have a new way of mobility. Part of the autonomous and safety equipment (Advanced Driver Assistance Systems = ADAS) are radar and lidar systems to analyze the surroundings of the car.

Figure 2 shows as an example the Porsche Macan Distronic Radar made by Automotive Tier-1 Bosch.  Main components are the front cover which is often referred to as radome, the back cover, together with the RF absorber and circuit boards. In this material selection example we focus on the radome element.

Figure 2:  Porsche Macan Distronic Radar made by Automotive Tier-1 Bosch.

Funnel stage 1: Material selection factors

In Funnel stage 1 we assess the requirements which need to be fulfilled by the radome material:

• Environment including temperature rating: exposure to UV-light and resistance towards weatherability conditions is needed;
• Radar transparency: low dielectric constant (Dk) and low dissipation factor (Df) since low values mean better dielectric materials with less dielectric heating which is needed for high-frequency applications such as radar equipment. Estimated according to the ASTM D2520, ASTM D150 (estimated at @Frequency 1.00e+6 Hz) or IEC 60250. Df should be between 10 and 200; loss tangent of 0,01 in the ultra-wide 79-GHz millimeter wave band. The dielectric constant should in the range of 3 @76 GHz (rule of thumb).
• Temperature rating (HDT @ 1.82 MPa): min 200 °C
• Mechanical requirements: resistance towards stones; impact modified materials; 
• Chemicals and chemical compatibility: salt and salt water; 
• Space layout: limited; dimensions of radom are given; integration into car bumper; 
• Lasting: 5.000 hours
• Costs: medium to higher cost range possible; 
• Recyclability: must be given at end of life;
• Laser welding: is optional;

Table 1 summarizes the important requirement information (requirement worksheet).

Table 1: Requirement worksheet of Funnel stage 1. 

Funnel stage 2: Decision on thermoplastic or thermoset

In Funnel stage 2 we assess whether a thermoplastic or thermoset material is able to fulfil the described requirements from step 1. Thermoset polymer matrix as Radar dome materials are used in aircraft and airspace, however in Automotive production lot numbers are ranging in the million parts per year. Since we need longer cycle times in thermoset moulding compared to thermoplastic moulding, together with better impact performance of thermoplastics, selection is made for the thermoplastic route. 

Since we selected the thermoplastic root, we can choose between semi-crystalline and amorphous polymers. In our case we continue on the semi-crystalline route which allows for better chemical resistance compared to certain amorphous grades. 

Among the semi-crystalline engineering polymers we have Polyamides (aliphatic short- and long chain), Polyester (PBT), and POM.

For further decision making on the base polymer type, it helps to check the Dielectric Constant (ε) of different materials (Figure 3). 

Figure 3: Dielectric Constant (ε) of different materials.

Next, let us check the polarity of base polymers. Polar polymers such as PMMA, PVC, Polyamide, and PC absorb moisture from the environment and this in turn will raise the dielectric constant and lower the resistivity. Temperature (10-degree rule) accelerates the chain movement and enables dipole polarization which further decreases the insulation properties of such polymers. On the other hand, non-polar polymers such as PE, PP, PS, PTFE, and PPS are not affected by changing the electrical properties when exposed by moisture and temperature increase. 

PBT absorbs much less water compared to aliphatic Polyamides and it keeps its dimensional stability in dry and wet environments. Dielectric constant (Dk) and low dissipation factor (Df) are in a good range too and this leads to a search in PBT grades from different material suppliers on databases such as CAMPUS or Omnexus. 

We found the following four PBT grades suitable for Radar domes, which have laser weldability, hydrolysis resistance, strength, toughness, and low Warpage (Table 2): 

• TORAYCON™ 1101G-30H
• TORAYCON™ 4158G-30H (laser welding)
• Pocan B1205XHR 
• Sabic LNP™ THERMOCOMP 6F006

Other options in the high performance polymer segment for radomes would be PPS or PEI. 

Table 2: Overview pre-selected thermoplastics.

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

Now we have reached the heart of the Polymer Selection Funnel method: the qualitative matrix analysis. First we rank how good each of the materials can fulfil the requirements from step 1 (0 to 5=best), followed by secondly, assigning priorities to each of the requirements (0 to 5 = highest priority). Finally a multiplication of the requirement fulfilment with the priority is done and the values are added up for each material. Table 3 summarises the outcome of this process.

The grades 1101G-30H, 4158G-30H, and THERMOCOMP 6F006 are close together in result points followed by B1205XHR. 

Table 3: Result of the qualitative matrix analysis. 

Funnel stage 4: Testing, selection of material and vendor

In the final stage of the funnel we test and validate the pre-selected grades from the outcome of Funnel step 3. If laser weldability, together with excellent Radar transparency is the focus, then 4158G-30H and THERMOCOMP 6F006 will be in the validation focus. Otherwise, 1101G-30H and B1205XHR can be evaluated too. After ordering sample materials and designing a prototype tool or 3D printing parts, evaluation on part level can start. Depending on the OEM testing standard, several investigations need to be performed, especially Radar transparency at different frequencies needs to be evaluated. In our case, 1101G-30H, THERMOCOMP 6F006, and B1205XHR are good material choices. If assembling with the base house of the Radar using laser welding is needed, then further tests need to be conducted. 

Request a sample of the shown plastic compounds here 

Conclusions 

There are several advantages in the use of engineering polymers such as PBT for Radar radomes and ADAS applications in general:

• Low dielectric constant
• Low dissipation factor
• Excellent mechanical properties (high strength and modulus; high impact resistance)
• Weatherability and UV resistance
• Processing via injection moulding in high numbers
• Low water absorption

By using the four step Polymer Funnel method we could systematically find the optimum material for our radome application. 

More polymer material selection examples can be found in my "start here" section. 

Thanks for reading and #findoutaboutplastics!

Greetings, 

Herwig 

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

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

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

My personal website

Literature: 

[1] https://lanxess.com/de-DE/Presse/Presseinformationen/2021/08/LANXESS-entwickelt-Konzept-fuer-Radarsensoren-mit-integriertem-Waermemanagement

[2] https://www.curbellplastics.com/materials/industries/radomes/

[3] https://www.rohde-schwarz.com/cz/applications/characterizing-the-material-properties-of-polymers-for-radomes-and-bumpers-to-optimize-radar-transparency-application-card_56279-1233408.html

[5] https://www.diva-portal.org/smash/get/diva2:1136102/FULLTEXT01.pdf

[6] https://radar-blog.innosent.de/en/design-of-a-radome/ SG

[7] https://www.generalplastics.com/technical-papers/dielectric-materials-use-radomes#:~:text=POLYURETHANE%20FOAMS%20IN%20RADOMES%3A,performance%20of%20the%20antenna%20inside. SG

[8] https://www.ti.com/lit/an/swra705/swra705.pdf?ts=1683015383043 SG

[8] https://solutions.covestro.com/-/media/covestro/solution-center/brochures/pdf/ep_sensor-brochure_en_final.pdf

[9] https://www.accenture.com/us-en/insights/automotive/electric-vehicles-on-the-rise

[10] https://www.ebay.de/itm/125432456436?var=0&mkevt=1&mkcid=1&mkrid=707-53477-19255-0&campid=5338765354&toolid=20006&_trkparms=ispr%3D1&amdata=enc%3A1jh97u_e2TWSBwLjLmt1fJg69&customid=DE_131090_125432456436.153165883401~2079861677694-g_CjwKCAjwyqWkBhBMEiwAp2yUFlS_64OthQZ9tiDysgItcO7RHcRvbMZDNISXMnUsyV5HxayPttmmRhoCa28QAvD_BwE

[11] https://www.generalplastics.com/technical-papers/dielectric-materials-use-radomes

[12] https://www.plasticstoday.com/automotive-and-mobility/new-pbt-slashes-dielectric-loss-without-compromising-dimensional-stability

[13] https://passive-components.eu/what-is-dielectric-constant-of-plastic-materials/

Sustainable Materials - Comparing the Melting Energy of High Performance Polyamides vs. Metals

Hello and welcome to another post. In today's post we compare the melting energy of high performance polyamides such as PPA (6T/6I) towards the melting energy of metals (Aluminum, brass, and others).

The big success of metal replacement with high performance polymers

In my previous posts (Example of metal replacement with engineering thermoplastics  , Metal replacement with High Performance Polymers: How to Design for Equivalent Part Stiffness? , Metal Replacement with Polyarylamide (PARA) for Single-Use Surgical Instruments ) we already discussed the advantages of metal replacement with high performance polymers. Main drivers are:

-cost and weight saving 

-possibility of consolidating several metal parts into one plastic part

-enable a better resistance to corrosion or chemical attacks. 

-improving acoustics (particularly relevant in electric vehicles) can be improved, together with an improved friction and wear of parts.

-low input of energy to transform plastics and produce parts.

The last point we deepen and discuss some interesting data on this. 

Comparison of melting energy

Figure 1 compares the melt energy of a partially-aromatic Polyamide (PPA - 6T/6I) with metals such as Aluminium, Brass, and Magnesium. Melting brass needs 283% more energy compared to melting the PPA. Aluminium ranks right behind with 105%, and Magnesium with 51%. Metal die casting parts are made by using high temperatures and producing the metal alloys needs a high amount of energy too.

Figure 1: Comparing the melting energy of metals vs. PPA [1].

This is a major drive why metal prices increased in the past six months and high performance polymers represent a low energy alternative for several industries such as automotive.  In part design, over 60% of the production costs are decided in the beginning of the design project. Comparing different materials in the material selection phase will result in a more optimal and low energy material in the end.

Thanks for reading and #findoutaboutplastics

Greetings, 

Herwig 

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

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

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

My personal website

Literature: 

[1] https://www.k-aktuell.de/technologie/ems-chemie-metallersatz-spart-energie-94763/

Virgin vs. recycled glass-fiber PPS: How much can the carbon footprint be lowered?

Hello and welcome to a new post. Today’s post deals with the question of how much the carbon footprint of 40 wt% glass-fiber reinforced PPS can be lowered. Using a low carbon footprint polymer may be on your requirement list for material selection and thus we have a brief look at this topic. 

Several options to decrease Global Warming Potential of thermoplastics

There are more than one way to lower the carbon footprint of a polymer. For instance, one can use a base resin which has a lower carbon footprint by its manufacturing process. As an example, Polyketone is mentioned, which has a Global Warming Potential (GWP) of 3.08  kg CO2 eq, whereas Polyamide 6 has a GWP of 6.70 kg CO2 eq. Another way is to use recycled fillers such as recycled glass- and carbon fibres. Also, using natural feedstock for monomers and applying a mass balance approach is another great option and widely used already among engineering and more and more with high performance polymers too. 

Example standard 40 wt% glass-fibre reinforced PPS

Speaking of high performance polymers, Polyphenylene sulfide (PPS) is often used for applications in high temperature, stringent chemical environments and often I receive the question how much the carbon footprint can be lowered of a standard 40 wt% glass-fiber reinforced PPS? 

I have already some experience with recycled PPS usage (my regrind Rule of Thumb post) and I searched for some data on this interesting question. Starting from 5.43 kg CO2 eq of a standard PPS-GF40 grade, carbon footprint could be lowered to 3.01 Kg CO2 eq, reducing the greenhouse emissions by about 2.42 kg CO2 eq (Table 1). The calculation are based on the ISO 14067 standard. The low carbon footprint PPS uses 50 wt-% post industrial recyclates to achieve such a reduction. 

Table 1: Reduction of the carbon footpring of PPS by using recycled material [1]. 

Update: recently I came across a 40 wt% glass-fiber reinforced PPS which has 0.619 kg CO2 eq which uses recycled PPS to lower the carbon footprint [3].

More on the topic can be found here (eco-profiles of polymers)

Thanks for reading and #findoutaboutplastics

Greetings, 

Herwig 

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

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

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

My personal website

Literature: 

[1] https://plasticker.de/news/shownews.php?nr=43176&nlid=64581.d.h.2023-06-01

[2] https://plas.tv/?p=33837

[3] https://www.convena-polymers.de/News-63?news_id=33