The developed prototype materials had good anti-ballistic performance but usage of this substance could be dangerous to people involved in the production of the monomer and copolymer, the company reports.

Severely toxic

In recent years Teijin Aramid has been engaged in an R&D programme together with several international partners to develop and commercialize aramid copolymers containing DAPBI (5(6)-amino-2-(p-aminophenyl) benzimidazole).

The programme was aimed at further improvement of the performance of aramid polymers, mainly for anti-ballistic applications. After a thorough investigation it was found that the DAPBI monomer is mutagenic, severely toxic to the kidneys at very low dosages, toxic to reproduction and possibly carcinogenic.

Anti-ballistic products

Teijin Aramid’s current polymer for Twaron contains two monomers (building blocks) called PPD and TDC. In copolymer yarn, part of the PPD is replaced by a different building block called DAPBI, to achieve a further reduction in weight of personal body armour at the same threat level.

Teijin Aramid gives highest priority to the safety of persons involved in the whole supply chain and it was therefore decided to stop the development and commercialization of these DAPBI-containing copolymer yarns.

Teijin Aramid will continue to develop next generations of anti-ballistic products with improved performance like Twaron Ultra Micro, the ultra-microfilament fibre, which was launched in January 2013.

Teijin Aramid

Teijin Aramid is a subsidiary of the Teijin Group and a leader in aramids. Its aramid products Twaron, Sulfron, Teijinconex, Technora and its ultra-high molecular weight polyethylene (UHMW-PE) Endumax are renowned for their strength, sustainability, safety, heat resistance and low weight. These high performance materials are produced in the Netherlands and Japan.

www.teijinaramid.com