PFAS-free Transparent Flame-Retardant Polycarbonate Debuts

South Korea’s Samyang Corp. has developed an eco-friendly transparent flame-retardant polycarbonate (PC) that is totally free of per- and polyfluoroalkyl substances (PFAS).

Artificial substances composed of carbon and fluorine, PFAS are widely used in electrical and electronic products, food packaging, cosmetics, textiles, and firefighting equipment because of their thermal stability and resistance to water and oil. Termed as "forever chemicals" due to their resistance to natural decomposition, they accumulate in the environment and human body, causing environmental pollution and health issues such as tumors, thyroid disruption, and hormonal imbalances, according to some experts. The United States has already started regulating PFAS, and the European Union is pushing for legislation to ban their use, including in harmful chemicals. Other countries also are moving toward restrictive regulations.

Samyang commissioned global inspection and testing company SGS to test for 74 types of PFAS in this test. Key substances tested for included perfluorooctanesulfonic acid (PFOS), which can cause chronic renal failure, and perfluorooctanoic acid (PFOA), known to increase the rate of birth defects and cause various severe diseases such as cancers and thyroid disorders. In addition, tests were conducted for perfluorohexanesulfonic acid (PFHxS), perfluoroalkyl carboxylic acids (PFCA), and various per- and polyfluoroalkyl substances. The results showed no detection of these substances.

Halogen-free flame retardancy

Samyang’s transparent flame-retardant polycarbonate is an eco-friendly material developed by changing the molecular bonding structure based on silicone polycarbonate (Si-PC), without adding halogen-based flame retardants like chlorine and bromine, which generate toxic gases when incinerated. The material overcomes the drawbacks of traditional flame-retardant PCs, namely lower transparency and impact strength, while its chemical resistance and low-temperature impact strength are superior to standard polycarbonate.

Flame-retardant performance is also reported to be exceptional, having obtained the highest rating of V-0 in the UL 94 vertical burn test. V-0 is only awarded to plastics that self-extinguish within 10 seconds when ignited vertically.

Samyang Corp. plans to expand the use of this material in various industries requiring transparency and flame-retardancy, such as automotive and home appliance exteriors and interiors, sound barriers, and medical device parts, based on its capability to maintain mechanical properties at a similar level to regular polycarbonate even when processed into thin films of about 1 mm thick.

From fishing nets to auto interiors

Further, Samyang is accelerating its expansion into an eco-friendly materials business. Last year, it developed the country's first PC containing more than 90% of post-consumer recycled polycarbonate (PCR-PC). Additionally, it has signed a supply contract with the fishing net recycling company Netspa and is developing plastic compounds for automobile interiors and exteriors, electronic devices, and household goods using recycled plastic pellets from fishing nets, with commercialization on the horizon.

In addition, group company Samyang Innochem has completed a 15,000-tonnes/year plant for the production of isosorbide from corn. This precursor can be used as a raw material for bioplastics. Finally, Samyang Packaging is expanding its recySOURCE recycled PET resin business with a 21,000-tonnes/year facility in Sihwa, South Korea.