Teijin Aramid, a subsidiary of fiber manufacturer Teijin, announced on Wednesday that it has stopped its research in developing and commercializing aramid copolymers containing Diamino-2-phenylbenzimidazole (DAPBI) due to concerns that it could possibly be carcinogenic.
The current polymer used for Teijin Aramid’s Twaron products contains two monomers, or building blocks, called PPD (paraphenylene diamine) and TDC (terephthaloyl dichloride). In copolymer yarn, part of the PPD is replaced by a different monomer called DAPBI, in order to achieve a reduction in weight of personal body armor, while still remaining at the same threat level.
According to a statement, the prototype materials developed had good anti-ballistic performance. But following a thorough investigation, the subsidiary found that it could be dangerous to researchers involved in its production as the DAPBI monomer is mutagenic and severely toxic to the kidneys at very low dosages, as well as to reproduction.
Teijin Aramid said its number one priority is the safety of its workers and that it will continue its development of next generation anti-ballistic products with improved performance, such as Twaron Ultra Micro, launched in January 2013 as the world’s first ultra-microfilament fiber.