Evaluating High-Temperature Performance: DMA Comparison of PARA-GF50 vs. PPA(4T)-GF50

Hello and welcome to a new blog post in which we evaluate the high-temperature performance of PARA (PA-MXD6) vs PPA.

When selecting materials for demanding, high-temperature applications, understanding their mechanical performance under heat is critical. Dynamic Mechanical Analysis (DMA) is a powerful tool for assessing how polymers retain their stiffness as temperatures rise. In this post, we compare the high-temperature behavior of two advanced engineering plastics: PA-MXD6-GF50 (50 wt% glass fiber reinforced Polyarylamide) and PPA(4T)-GF50 (50 wt% glass fiber reinforced Polyphthalamide). Both material fall into the category of semi-aromatic polyamides which reflect a resistance towards higher temperatures. In this post we check if this is the case for the both materials. 

DMA Results: Shear Modulus vs. Temperature

Figure 1 presents the dynamic shear modulus (E') of both materials as a function of temperature. The glass transition temperature (Tg) is a key indicator of when a polymer’s mechanical properties begin to decline:

• PA-MXD6-GF50 (PARA): E' drops sharply at around 85°C, marking its Tg.
• PPA(4T)-GF50: E' remains stable until approximately 125°C, indicating a higher Tg.

Beyond the glass transition, the differences become even more pronounced. Between 150°C and 200°C, PARA exhibits a slight plateau in modulus before dropping to zero at 250°C. In contrast, PPA(4T)-GF50 maintains a high modulus, retaining around 5 GPa even at 250°C. This demonstrates PPA’s superior ability to withstand elevated temperatures without significant loss of stiffness.

Figure 1: Comparison Dynamic Shear Moldulus E' of PARA-GF50 and PPA(4T).

Thermal Endurance: UL 746B RTI (Strength) Comparison

To further validate these findings, we examined the Relative Thermal Index (RTI, strength at 1.5 mm thickness) according to UL 746B:

• PA-MXD6-GF50: RTI (strength) = 105°C
• PPA(4T)-GF50: RTI (strength) = 130°C

The higher RTI value for PPA(4T)-GF50 confirms its suitability for applications requiring long-term mechanical integrity at elevated temperatures.

Ways to increase the thermal performance of PARA / MXD6

Increasing the thermal resistance of PARA/MXD6 can be done by blending PARA with PPE  (Polyphenylenether) and make a MXD6/PPE alloy which not only exhibits high temperature resistance, high strength, but also good and wear resistance.

Conclusion: Material Selection for High-Temperature Applications

DMA provides valuable insight into how materials behave under dynamic loading across a temperature range. For applications operating above 120°C, PPA(4T)-GF50 clearly outperforms PA-MXD6-GF50, maintaining higher modulus and demonstrating better thermal endurance. Alongside DMA, considering the RTI value is essential for making informed material choices in high-temperature environments.

In summary:

• PPA(4T)-GF50 offers superior high-temperature performance and stability.
• PA-MXD6-GF50 is suitable for applications up to its Tg and shows property loss at higher temperatures above 200°C.

Selecting the optimal material ensures reliability and safety in demanding thermal conditions. 

Nevertheless, PARA is outperforming PA and PPA in terms of stiffness, combined with excellent surface aesthetics and lowest water uptake allowing for high dimensional stable parts. 

More on PA-MXD6 / PARA here: 

Design Properties for Engineers: The ABCs of Polyarylamide (PARA; MXD6)

Polyarylamide vs Polyamide (PARA vs PA): What are the Major Differences Between PARA and PA (Polymer Material Selection Tip)?

Design Properties for Engineers: The ABCs of Polyarylamide (PARA; MXD6)

PA6.6 vs. PARA - Reducing the Wall Thickness of Injection Moulded Parts (Geometry Optimization Example)

Design Data for PolyArylAmide (PARA; PA MXD6) Selection: Mechanical Properties as Function of Temperature and Humidity

Mastering Injection Molding Tools for High Performance PolyArylAmide (PARA; PA MXD6): 6 Key Steps to Success

Design Properties for Engineers: Superior Gas Barrier Properties of PolyArylAmide (PARA; MXD6)

Check out my Micro Training below too:

And my dedicated Polyarylamide Hub here.

Thanks for reading & #findoutaboutplastics

Greetings,

Herwig Juster

📚My Polymer Material Selection Book - Available Here

📊 Discover your Polymer Material Selection score by taking quick test here

🎥Join my YouTube channel community 

🔎Join my inner circle (monthly newsletter)

Literature:

[1] https://www.syensqo.com/en/brands/ixef-para

[2] https://plasticsfinder.envalior.com/en/datasheet/ForTii%C2%AE+Ace+MX53/O4A8W

[3] https://www.nexeoplastics.com/types/plastics-database-datasheet?id=2131&product=Ixef%C2%AE&grade=1022

[4] https://www.orinkoplastic.com/PA-6I-6T-And-MXD6-pl60644367.html

[5] https://www.polyarylamide.com/

Polymer Selection Funnel Example - Panhandle (Consumer Goods Material Selection)

Hello and welcome to another material selection example using the Polymer Selection Funnel method (POMS-Funnel-Method; in detail explained here and in this video). Aim is to select the optimal polymer material for a panhandle which most of us are familiar with and have in our kitchen. 

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 - overview of the four different funnel stages .

Polymer material selection for a kitchen panhandle

This panhandle is used in professional environments as well as in everyday life kitchens (Figure 2). It needs to cover a range of requirements which we understand better by following our polymer material checklist which consists of 12 sections and can be downloaded here. 

Figure 2: Overview of a pan with the handle. Aim is to select the optimal polymer for this handle. 

Funnel stage 1: Material selection factors

In the first Funnel stage we focus on gathering and understanding all the requirements of the panhandle

For this product, the minimum requirements according customer specification are:

-Continuous operating temperature (long-term heat resistance): 130°C

-Short term heat resistance: HDT-A between 290°C and 320°C

-UL94 fire rating: HB at all thickness levels

-Good stiffness level at elevated temperature: min 5 GPA storage modulus at 100°C

-Food contact approved including EU 2011-10 and FDA

-Dishwasher use proof

-Good surface appearance (black color)

-Economical: handle must be produced using water coolable moulds with high productivity 

-Product Carbon Footprint: < 7  kg CO2/kg

-Easy cleaning an low sticking properties

-Good impact performance in case of dropping the pan

Furthermore, in Table 1 we summarized all important requirement information (requirement worksheet).

Table 1: Requirement worksheet for the panhandle. 

Funnel stage 2: Decision on thermoplastic or thermoset

Reflecting on the must-have requirements which need to be fulfilled, thermoplastics present the optimal choice. Thermosets will struggle with the food contact regulations, together with the mechanical properties, in particular the impact performance, since they are hard and quite brittle. However, There are Bulk Moulding Compounds (BMCs) such as the BMC 1000 from LyondellBasell Industries which use Unsaturated Polyester as base polymer, have food contact approval and may be a suitable grade for this application. 

Amorphous polymers are transparent and have good temperature and mechanical performance. They are prone to stress cracking, have a lower chemical resistance (dishwasher cleaning agents) and their fatigue performance is lower compared to semi-crystalline polymers too. On the other hand, semi-crystalline engineering polymers have good high heat performance, together with good chemical resistance and mechanical properties. 

After this analysis we can make a preselection of suitable grades which can be discussed in Funnel stage 3. 

Table 2 lists all selected grades and their commercial suppliers. The pre-selected materials are PPA with 40 wt% glass fiber (Amodel® FC-1140 L;  Syensqo), PA 4.6 with 30 wt% glass fiber (Stanyl® TE200F6-FC; Envalior), PPA+PA blend with 50 wt% glass fiber (Omnix® FC-4050; Syensqo), and UP with glass fiber loading (BMC 1000 FC; LyondellBasell). 

Table 2: Overview preselected grades and their commercial suppliers.

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

In the  third funnel stage the matrix analysis takes place. We use the qualitative decision-making process to rank the preselected polymers from Funnel stage 2.

First we access the online tool I developed to facilitate this step here (Polymer Material Selector V1.1). Alternativ, you can reach out to me and i will provide you with an excel version of it. I only considered the must-have requirements. 

The qualitative matrix analysis has three major steps: in the first step we rank how good each material can fulfil the requirements (0 to 5=best), followed by an assignment of the priorities to each of the requirements (0 to 5 = highest priority). The two steps can be done in reversed order too. In the third step we multiply the requirement fulfilment with the priority and add the values up. 

Table 3 summarizes the outcome of the qualitative matrix analysis.

In our case, PPA-GF40 (score: 173 points) and (PPA+PA)-GF30  (score: 157 points) rank number and number 2 respectively, followed by PA 4.6-GF30 (score: 144 points). All three materials should be validated in the Funnel stage 4. Due to the thermal shock and impact performance needed for this application, UP-GF (elongation at break between 0-1.6%) may result in a too brittle material choice and will not be further tested. 

Table 3: Qualitative matrix analysis for the panhandle. 

Funnel stage 4: Testing, selection of material and vendor

Part and system components, as well as  application specific testing with the PPA, PPA+PA, and PA 4.6 materials from Funnel stage 3 takes place in this final Funnel stage 4. Also, processing and tool making are checked to avoid unseen hurdles in the production at a later stage. Final material selection and vendor selection can be done once all the results are obtained.

In our case, we selected the PPA-GF40 for the premium consumer goods segment and the (PPA+PA)-GF30 as  a more cost-efficient solution for the standard segment. PA 4.6 can be considered for the standard segment too. 

Conclusions

In this example we showed the application of the Polymer Selection Funnel methodology for selecting the optimal food contact grade for panhandle. It is a systematic approach with a resin-agnostic view allowing to consider different material choices. 

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

Polymer Material Selection Funnel Example - Baby Bottles (Consumer Packing Example)

Polymer Selection Funnel Example - Vacuum Cleaner Canister and Canister Holding (Example Electronics Consumer Goods)

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

My online selection tool: 

Polymer Material Selector V1.1

Thanks for reading and #findoutaboutplastics

Greetings,

Herwig 

📚My Polymer Material Selection Book - Available Here

📊 Discover your Polymer Material Selection score by taking quick test here

🎥Join my YouTube channel community 

🔎Join my inner circle (monthly newsletter)

Literature:

[1] https://www.lyondellbasell.com/495bd8/globalassets/products-technology/advanced-polymer-solutions/technical-data-sheets/bulk-molding-compounds/bmc1000.pdf

[2] https://www.matweb.com/search/datasheettext.aspx?matguid=92fbe362c23e4f248abc812a859eb21e

[3] https://www.matweb.com/search/datasheet.aspx?matguid=c9a9ff9a99ca46df81c2e21178e0f2ed&n=1&ckck=1

[4] https://plasticsfinder.envalior.com/en/application/datasheet/2rQz4

Material Selection Considerations for Electric Vehicles (EV’s) - Thermal Management Systems

In this post, we will have a closer look at the key considerations for thermal management systems used in electric and hybrid cars. This can support an optimal selection of plastic materials.

Traditionally, in internal combustion engine cars a powertrain thermal management and a passenger cabin thermal management system are present. Here, it well understood which type of plastic materials can be used depending on the application requirements.

In EV’s, thermal management systems support additional systems such as:

• Lithium battery: Thermal management systems need to ensure operating temperatures of 40-45°C to maximize battery service life. Composing parts need to retain material properties after 6.000-10.000 hours to ensure safe handling. Thus, precise control of temperature deltas is crucial.

• Traction motor: Thermal management systems need to ensure operating temperature of coils up to 190°C to allow high torque at small size.

• Power electronics: For high power electronic controllers, liquid cooled systems are favored and plastic materials used in housing need to have a thermal conductive role.

• Hybrid EVs: Downsizing of the combustion engine leads to local hot spots, which thermal management systems need to be able to handle.

What are the market trends and emerging needs?

For internal combustion engines increased temperatures due to downsizing of engines are expected. Simultaneously, more and more turbocharging systems need to be used to compensate the missing engine performance. EV’s have a system temperature ranging from 70°C to 80°C. The latter makes polyolefins accessible for thermal management applications.

Furthermore, in battery EV’s an increased aging exposure to water glycol coolant from 3.000 up to 6.000 till 10.000 hours is expected. Thermal management systems need to be active during charging time as well as when the surrounding temperatures are extremely low. Also, when the EV is not operating, temperature is monitored and in case extreme temperatures are reached, thermal management systems have to be activated too.

All this leads to ongoing discussions at the OEM and Tier-1 level on the requirements, which can be summarized as follows:

1) Coolant fluid temperature: ranging from 80°C to 110°C

2) System pressures: can reach up to 3 bar

3) Increased lifetime: up to 10.000 hours

4) Use of dielectric conductive coolant fluids

New design challenges

As mentioned in the beginning, having additional systems such as the battery, traction motor and power electronics for monitoring tasks require higher complexity thermostat valves which need to fulfill a more precise control. Temperature deltas between one battery module and the next module can be as stringent as 1°C.

Since available space for battery module placement is limited, the design of thermal management systems must be compact. Long operation times (during driving, charging and parking) and chemical resistance of water glycol coolant fluids represent another design challenge. One of the most critical challenges is the material strength which includes the weldline strength, especially after long term aging exposure.

Weldlines represent always the weak point of the plastic application, since the connection is weakened due to random orientation of glass fibers in the connection area. In addition, weldline strength is further weakened by water glycol aging. Since we will be dealing with more complex parts, weldlines are unavoidable and need to be taken care of.

Can all this be handled by plastics? - Yes, but only with the proper material selection

Let us summarize the key considerations for our material selection and give suitable polymer examples:

1. Aging temperature: 120-150°C: Polyphenylene sulfide (PPS); 120-135°C: Polyphthalamide (PPA)

2. Aging time: 1.000 – 3.000 hours: PPS and PPA; > 6.000 hours: PPS or PPA based on required temperature.

3. Increased chemical degradation due to different coolants: PPS has best in class chemical resistance.

4. Dimensional stability for sealing tasks: PPS and PPA.

5. Secondary operations such as laser welding: PPA has good laser welding capabilities.

PPS and PPA show promising mechanical behavior even when exposed to high temperatures, water-glycol coolant and long aging time.

Figure 1 shows mechanical data of PPS after exposure to water-glycol coolant (Ryton® R-4-220BL, Solvay). Figure 2 shows the mechanical data of a suitable PPA for water-glycol applications (Amodel® A-1933 HSL, Solvay).



Figure 1: Mechanical data of PPS after exposure to water-glycol coolant (Ryton® R-4-220BL, Solvay).

Figure 2: Mechanical data of a suitable PPA for water-glycol applications (Amodel® A-1933 HSL, Solvay).

PPS and PPA: not all grades are equal

PPS has unbeatable chemical performance due to the benzene sulfide group in the backbone. When exposed to water-glycol coolant, the PPS polymer matrix can withstand long aging times. However, attention needs to be payed to the glass fiber sizing. The same applies to PPA grades as well.

Interfacial adhesion of the polymer to the glass fiber is achieved over the sizing which is coated onto the glass fiber. Standard glass fiber sizings are cleaved when exposed to glycol and thus the mechanical values drop. Therefore, special sizings are used when the final compound is exposed to glycol. When your application is exposed to coolants, using of glycol resistant glass fillers is a must. The compounds shown in Figure 1 and 2 use such glycol resistant glass fiber fillers.

Material recommendations

Table 1 shows a recommendation concerning material selection for EV’s thermal management system based on existing data.

Table 1: Comparison of PPS and PPA for EV thermal management systems

Comparison PPA and PPS for thermal management systems

Overarching, high performance and engineering plastics will find more and more applications in EV thermal management systems.

If you would like support in the material selection of thermal management systems (from polymer to supplier) for ICE and/or EV feel free to get in contact with me. We can discuss your project.

Thanks for reading & till next time!

Greetings,

Herwig Juster

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Interested in my monthly blog posts – then subscribe here.
New to my Find Out About Plastics Blog – check out the start here section
Check out also my personal webpage.

Literature
[1] https://www.solvay.com/en/brands/ryton-pps#Design-Guidelines
[2] https://www.solvay.com/en/brands/amodel-ppa#Grades

Polymeric Material Selection: A Critical Factor In Making Successful Plastics Parts

Holding a high quality plastic part in your hands is a result of several product development steps. Having your product development and production process strategy properly aligned is half the success. The other half comes by considering five factors which influence your outcome in having best in class injection moulded parts (Figure 1) [1]:

1. Part design: there are design rules for plastics part, especially for injection moulded parts which need to be followed. Polymers have anisotropic behavior compared to isotropic metal parts.
2. Material selection: once application requirements are established and the base design of the part is done, selecting the material can start.
3. Mould design and construction: designed in a way that the mould can withstand the moulding process and the polymer.
4. Moulding machine selection: when the mould design is completed, the injection moulding machine selection should be done or it can be done in parallel to the mould design, depending on the data available.
5. Moulding process: optimization of the process is the last step and often done incorrectly or not at all.

Figure 1: “From Art to Part”: Material Selection as one critical factor in successful plastic part production [1].

In this post, I keep the focus on the “material selection” factor, since it is a vital one. After the basic part design is done, it is time to review the part performance requirements. In general, a separation of material selection based on performance, processing, and costs can be done. Following questions you need to answer for your part:

- Which areas of performance do I need to consider for this application?

- Are mechanical performance criteria (strength, stiffness, toughness) dominating?

- Are electrical performance criteria (insulating polymers vs. conductive polymers) dominating?

- Are environmental effects (temperature, chemicals, radiation, time) dominating?

Furthermore, tolerance criteria on the part itself need to be taken into account. In case you have a tight tolerance part, low shrinkage materials are the preferred choice. Having thick sections in your part, filled polymers can help obtaining a good filled part.

After gathering all the data which is needed to answer the questions from above, you can start your material selection procedure and make your material shortlist for decision making. Usually, a typical material selection procedure covers three steps [3]:

1. Application screening
2. Generic family and specific grade identification
3. Process selection and cost analysis

These three steps reconcile with the five critical factors for the making successful plastics parts.

Here are 9 more tips what can be considered in the phase of material selection [2]:

1. Stress/strain curve: for plastics the stress/strain behavior is usually not linear up to yield. There are cases where the yield may be very slight or does not exist at all.
2. Modulus of elasticity in tension vs. compression: the E-modulus in tension is not necessarily the same as that in compression.
3. Young’s modulus (E-modulus): the plastic modulus of elasticity is low compared to that of metals.
4. Plastics show anisotropic behavior: injection moulded parts made out of fiber reinforced plastics demonstrate anisotropic behavior.
5. Mechanical behavior: in plastics parts mechanical behavior is influenced by the rate of straining of the material. It is a function of temperature and time as well.
6. Creeping: in comparison to metals, plastic parts creep under load with time.
7. Reduction in strength: plastic parts show a decrease in the strength with time. This is the case with static loads too.
8. Environmental conditions: material properties of polymer-based products may change in certain environmental conditions.
9. Additive package: most plastics have an additive package consisting out of heat stabilizers, fillers and glass reinforcements and this must be considered when specifying the material.
   

Once the material is chosen, the mould design (factor 3), injection moulding machine selection (factor 4) and processing (factor 5) can kick off.

Since there is not always a full engineering of the material properties needed, time saving material selection tips can help. Here are some rules of thumb for making an educated guess on plastics material selection [4]:

• Trying out acrylonitrile butadiene styrene (ABS): it works for many applications and is in a reasonable price range. It is strong and relatively though, combined with a low melting point and good processing properties.
• For a cheap solution and when surface aesthetics are not critical, polypropylene (PP) will do the job.
• For having increased temperature resistance as well as higher impact resistance, polycarbonate (PC) is the next best candidate going from ABS.
• For having a good overall aesthetics and transparency, polymethylmethacrylate (PMMA) is your material of choice. The downside is that it can be too brittle for certain applications. Considering a transparent PC, it will be tougher than PMMA, however the surface aesthetics might not fulfill your set of needs.
• For higher engineering demands, aliphatic nylons are the best way to go. Particularly, the polyamide 6.6-GF30 is well established in lots of engineering applications, especially in Automotive. When higher temperatures are needed (120-140°C), aromatic polyamides (e.g. polyphthalamide (PPA)) will do the job.

Apart of the aforementioned guides, I developed a systematic way of selecting polymers which uses a funnel method. Here you can read an introduction and my book on this topic is available here . 

Success with your next material selection!

Thank you for reading!

Herwig Juster

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] Distinctive Plastics Inc.:  The 5 critical factors to produce a succesfull injection moulded product, 2011

[2] B. S. Benjamin, "Structural Design with Plastics," Van Nostrand-Reinhold, 1961.

[3] Paul F. Kusy: Plastics Material Selection Guide, 1976

[4] Proto Labs: Materials Matter – The Material Selection Process