Reviewing Key Engineering Plastics – Polycarbonate [incl. Video]

Hello and welcome to this post on reviewing key engineering plastics. Today, we have a closer look at polycarbonate (PC).

Similarly to the last review on the aliphatic polyamides PA 6 and PA 6.6, we review the chemistry including the simplified petrochemical flowchart, discuss the properties and applications of polycarbonate and look at their global demand and producers.

Here you can find the youtube video of the review:

Before we start with the chemistry I would like to uncover the history of polycarbonate. In 1953, Mr. Fox from GE Plastics prepared the first sample of polycarbonate in his lab. At the same time, Mr. Schnell from Bayer AG discovered polycarbonate too. A patent fight between the two inventors started. This could luckily be settled, which allowed the start of the high volume production of polycarbonate.

General properties and chemistry

Polycarbonate is an amorphous polymer with a glass transition of 147°C and a melting temperature of 160°C. It is transparent and has a density of 1.2 g/cm3.

There are two processes to obtain polycarbonate:

1. Phase transfer process

2. Melt process route

The phase transfer process involves an interfacial polycondensation between phosgene (COCl2) and bisphenol A (BPA) in an organic solvent. It is a batch process suitable for specialty polycarbonate grades.

The melt process has been developed as an alternative to the utilization of phosgene due to environmental concerns. It consists of melt transesterification of BPA and diphenyl carbonate (DPC). DPC is obtained from dimethyl carbonate and phenol or directly over carbonylation of phenol. In a next step, DPC reacts with BPA to form polycarbonate precursors. With the precursors at hand, polycondensation takes place to obtain high molecular weight polycarbonate.

The melt process has been developed as an alternative to the utilization of phosgene due to environmental concerns. It consists of melt transesterification of BPA and diphenyl carbonate (DPC). DPC is obtained from dimethyl carbonate and phenol or directly over carbonylation of phenol. In a next step, DPC reacts with BPA to form polycarbonate precursors. With the precursors at hand, polycondensation takes place to obtain high molecular weight polycarbonate.

Simplified flow chart: Where does PC has its chemical roots?

As already mentioned, bisphenol A (BPA) is a major building block for PC. The simplified chemical flow chart helps us understand how BPA is produced. BPA production needs phenol which is obtained by the so called cumene process. Benzene and propylene are required in the cumene process too. In detail, benzene is alkylated with propylene which results in cumene. In a next step cumene is oxidized to obtain phenol and acetone. Acid catalyzed condensation of phenol and acetone leads to BPA. In a next step, BPA reacts with diphenyl carbonate to form polycarbonate.

Polycarbonate properties

Impact resistance, ductility, clarity, and dimensional stability are the major advantage properties of PC which makes it an excellent engineering plastic. Furthermore, PC has inherent flame resistance, good electrical properties and can be used at elevated temperatures up to 120-140°C. PC has a poor solvent resistance, limited hydrolytic stability and notch sensitivity. This needs be taken into account during your material selection.

PC global demand

In 2016, global PC demand was 4 million tons. The electrical and electronics markets make up for 27% of the total PC consumption. Next in line for PC consumption are the construction and the automotive markets, respectively. Geographically, one can state that Asia is the largest market for PC with 59% of its global consumption.

 
PC Price to performance
Polycarbonates form the base of amorphous engineering thermoplastics with a price of ca. 2.5 €/kg for base grades. High heat modified grades cost in the range of 3 to 3.6 €/kg.

PC end uses

PC covers a wide range of applications in different markets:

- Electronic components: good electrical insulator; heat-resistant and flame-retardant properties

- Construction materials: domelights, flat or curved glazing, and sound walls

- Data storage: Compact Discs, DVDs, and Blu-ray Discs.

- Transportation (Automotive, aircraft, railway, and security components): headlamp lenses, decorative bezels and optical reflectors

- Medical applications: complies with both ISO 10993-1 and USP Class VI standards

- Smartphones: cases, battery covers.

A new application field is battery cage housings and battery management systems components in electrical vehicles, including hybrid electrical cars.

A famous application was the use of Lexan® PC for the helmet visor of the Apollo moon mission 50 years ago.
I wrote a separate post on this topic which you can find here.


This was the review on polycarbonate, a versatile amorphous engineering thermoplastic used in many applications.

Thanks for reading & till next time!


Greetings,
Herwig Juster


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Literature
[1] https://pubs.acs.org/doi/10.1021/ie034004z
[2] https://nexant.com

Second Wave of Digitalization: From Plastics Machine Manufacturer to Platform Provider?

Second Wave of Digitalization

Thinking back to the last K-Show held in 2016 in Düsseldorf, Industry 4.0 and Industrial Internet of Things (IIoT) were all over the booths. This year at the K-Show we will see a lot about topics such as sustainability, circular economy, and recycling.

However, how did the Industry 4.0 story continue?

In the past three years, machine and equipment manufacturers, tool makers and plastic convertors connected their devices and started collecting data while making their products. This data allowed them to gain insights into their operations and make them more profitable. A major step stone was the introduction of Euromap 77 in 2018. This allowed data exchange between plastics converting machines e.g. injection moulding machines and manufacturing execution systems (MES). In this way, Euromap 77 enables a standardized way of connecting the entire production chain. Altogether, this first wave can be summarized under the term “efficiency innovation”. This was mainly driven to streamline internal processes and obtain cost reductions.

How does digitalization follow up?

Starting last year already, the second wave of digitalization [2] has arrived in Europe. In this second wave, investors focus on three main topics:

1. Artificial Intelligence (AI)

2. Platform based business models („platform economies“)

3. Mobility solutions

Artificial intelligence is the main game changer and impacts major traditional sectors such as banks and funds management. Adapting and changing your operations is major key to remain in business. For example, the most successful hedge funds managers, Ray Dalio with his Bridgewater Associates and Jim Simons with Renaissance Technologies have used sophisticated algorithms since the founding of their businesses. Now, the utilization of AI has enabled them to reach new levels of profitability.

Platform-based business models where profit is made by matching customers and producers belong to the most successful business models in the New Economy. There are several platform companies which are close or have already a stock valuation of 1 trillion USD. Microsoft (1.08 trillion Dollar) is the most valuable platform business followed by Amazon (961 billion Dollar), Apple (956 billion Dollar) and Alphabet (865 billion Dollar) [5].

Especially the third point “mobility solutions” is pushed by companies such as Amazon, which clearly places effort on having more vertical integration operations. For example, Amazon invested in the startup FlexPort to optimize its logistics so that the end consumer can be reached faster [3].

How is the plastics industry reacting to these three major drivers?

Plastic Industry 4.0 was and is all about making the use of things more efficient following the moto “faster, better, and cheaper.”

Apart of the efficiency steps, we see now first steps toward platform business models. For instances, the plastics machine manufacturer company, KraussMaffei, based in Munich set up his own market platform to tap into the material manufacturer pond. The platform is called “Polymore”. It represents a B2B marketplace to support sustainability in the plastics industry. It focuses mainly on compounds, recyclates and post-industrial waste, which serves plastic processors as well compounders. It will be launched at the K-Show in October later this year [1]. Although KraussMaffei is not producing resins or compounds, it can link polymer manufacturers and plastics convertors together and profit of the exchange. A similar platform is made by the company Matmatch (also Munich-based) which named its platform matmatch.com [4].

My interim conclusion

Plastics converting companies did not show exponential growth rates either, since fundamentally there was no change in their business models. Time will tell us, how the KraussMaffei approach will shake up the plastics industry. Creating a marketplace which not only offers materials, but also more and more plastics machinery, moulds and services combined with smart logistics and AI for sure hits the trend of second digitalization wave. With such platforms, companies gain access to customers and can leverage material capacities of other companies without having to own them. Market trends can be faster anticipated and customers better served. Traditional companies all along the plastics supply chain need now to re-think their business models.

Thanks for reading!

Till next time!

Best regards,

Herwig Juster

If you liked this post, share and like!
Interested in my monthly blog posts – then subscribe here.
New to my Find Out About Plastics Blog – check out the start here section
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Literature:
[1] https://www.polymore.com/en/home
[2] https://www.netzoekonom.de/2019/03/27/endspiel-um-die-digitalmaerkte/
[3] https://www.cnbc.com/2019/02/21/softbank-leads-1-billion-investment-in-logistics-start-up-flexport.html
[4] https://go.matmatch.com/materials-marketing-platform?utm_source=linkedin&utm_medium=paid+social&utm_campaign=Supp_Demo_SuppListsAll_EuropeNorthAmerica
[5] https://www.netzoekonom.de/plattform-index/

Take Me To The Moon – Celebrating 50 Years Moon Landing With High Performance Polymers

On July 20 1969, 50 years ago, Neil Armstrong and Buzz Aldrin touched ground on the moon. On this day, Neil Armstrong said the well known quote: “That's one small step for (a) man, one giant leap for mankind.”

The Apollo 11 crew was well equipped with latest technology. This included two high performance polymers constituting their helmet visors: polycarbonate (PC) and polysulfone (PSU).

Why were polycarbonate and polysulfone used for the helmet visors?

Polycarbonate as protective helmet visor:

Polycarbonate can be regarded as the benchmark for all existing impact resistant plastics. It got its name from the containing carbonate groups (−O−(C=O)−O−) in its backbone. These promote temperature and high impact resistance as well as an amorphous macromolecular structure which leads to excellent optical properties. High energy is needed to tear its chains apart. For these reasons, an ultraviolet-stabilized polycarbonate visor was used for protecting the heads of astronauts against impact and micrometeoroids. The protective visor could be moved independently of the sun protection visor. Back then, the Apollo mission used the newly developed polycarbonate Lexan® from GE Plastics [1].

Polysulfone as sun protection helmet visor:

Commercialized in 1965 by Union Carbide, Udel® Polysulfone (PSU) was right in time to be used as the external helmet visor. Polysulfone has a high service temperature (Tg = 190°C) in combination with reduced creep and dimensional stability. Among non-reinforced thermoplastics, polysulfone affords top high-temperature creep resistance. Another superior property of this plastic is that it retains its transparency after prolonged exposure to temperatures up to 200°C. This high temperature resistance property is to great extent imparted by the contained diphenyl sulfone groups. These characteristics made polysulfone suitable to be used as the sun protection visor (outer visor) in astronauts’ helmets [2,3], which 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.

Thank you for reading this recap history!

Greetings,

Herwig 

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Literature:

[1] https://www.hq.nasa.gov/alsj/alsj-LEVA.html
[2] https://www.space.com/26630-apollo-11-vintage-tech-innovations.html
[3] https://www.ge.com/reports/post/74545208407/ge-phone-home-ge-technology-helped-fly-humans-to/

[4] https://omnexus.specialchem.com/tech-library/article/apollo-11-moon-landing-plastics-applications

High Performance Polymers in Electrification: A Must-Have Or A Nice-To-Have (Part 3: Autonomous Driving)

Welcome back to the third part of the high performance plastics for electrification series. In the previous parts, we have discussed the polymeric materials used in battery systems and traction motors. Now, we a look at the high performance plastics used for autonomous driving applications.

Autonomous driving

• Connectors

Connectors need to be reliable while driving (manual and autonomous driving mode) as well as when the OEM is assembling the different parts of the car in the manufacturing line. Therefore, connectors need to fulfil different requirements:

• JEDEC MSL1 level of shelf life (=infinite);
• no corrosion (especially pins; plastic parts need to be free of halogens, red phosphor, and ionic heat stabilizers);
• continuous use temperatures of 140°C-180°C;
• high chemical resistance;
• high electric strength;
• and CTI of 600 Volts (PLC0).

Connectors need to have a high ductility level too. Easy identification of high voltage connectors, insulators, and circuit breakers is achieved by coloring polymers in orange (color coding compulsory above 60 V). Polymers such as polyphthalamide (PPA) with a Tg of 120°C and above (Tg of 140 up to 180°C are possible) can handle the requirements listed above offering high mechanical strength with low moisture uptake, similarly to polyesters. Apart of aliphatic polyamides and polyesters, semi-aromatic polyamides such as PPA and polyarylamide (PARA) can be obtained in a non-halogenated flame retardant compound. Advantages of PARA are the high stiffness, excellent low creep, low moisture uptake and impact properties.

• Light Detection and Ranging (LiDAR) and Radio Detection and Ranging (Radar) sensors

High performance plastics play an important role in connectors on the one hand as well as in sensors for autonomous driving on the other. An aliphatic polyamide absorbs water and moisture. This absorption is linked to a dimensional and mechanical change. LiDAR and radar housings need to be dimensional stable since their job is to scan the environment and create an accurate picture of the surrounding. Therefore, using polymers such as polycarbonate (PC), polyethersulfones (PESU), and polyphenylene sulfide (PPS) ensure the high dimensional stability combined with nearly no moisture uptake. Those polymers ensure safe communication of the different sensors over the life time of the vehicle.

• Battery temperature sensors

Minimal temperature changes (+/- 1 °C) in the Li-ion batteries can impact their loading efficiency. Therefore, accurate management of the temperature by sensors is essential for keeping the batteries at their highest effectiveness level. For this type of sensors, polyethersulfones are best suited since their Tg is around 220°C and they show excellent dimensional stability. Furthermore, this stability is needed for keeping the sealing performance of the sensor’s O-ring seals.

• 5G communication sensors

With the arrival of 5G mobile technology, our cars will be able to communicate with each other and the environment. Requirements for 5G related applications are mainly high speed data transmission, infrared transmission, retention of environmental influences and dimensional stability. Polymers such as polyether imides (PEI) and polysulfones are suitable to fulfill these requirements since their amorphous structure allows for tight tolerances and low CLTE, creep resistance and good IR transmission.

• Outlook

In next steps, automotive exterior designers start to seamlessly integrate LED lighting systems with infrared transparency for LiDAR sensor systems [1]. In such application concepts, polycarbonates can play an important role. The integration of LiDAR systems into the car bumper will lead to another challenge: having clean lenses. This may be ensured by using fluorinated coatings which are based on fluoropolymer chemistry (e.g.  perfluoropolyether - PFPE).

• Wrap-up

Electrification brings a whole mix of performance plastics in several applications. I have listed the material requirements and applications we discussed in this post including the previous two parts in two tables, which can serve as guidance through selecting the optimal polymer for your application.

Electrification application matrix for supporting polymer material selection



Material requirements of high voltage components in electric vehicles

Thank you for reading this third part of the electrification blog series! If you enjoyed it please do like and share it with your network.

Till next time!

best regards,

Herwig Juster

If you liked this post, share and like! 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: Herwigjuster.com


Literature:

[1] https://www.magnetimarelli.com/press_room/news/magneti-marelli-showcase-its-latest-technology-and-innovation-electronics-lighting