Teijin Aramid (Arnhem, The Netherlands) has introduced Twaron PVB prepreg, consisting of Twaron fabric and a new, specially designed polyvinyl butyral (PVB) thermoplastic matrix. The new prepreg is said to offer a long shelf life and stable ballistic performance over a broad temperature range. In addition, under heat and pressure it can be shaped into helmets, insert panels for ballistic vests or shaped panels for vehicle protection. Twaron PVB prepreg can be stored at ambient temperature for an extended period of time. Teijin says that competing systems currently used in the industry — based on PVB-modified phenolic resins — have a limited shelf life because they react to high temperatures and, therefore, eventually become unusable. Teijin reports that performance tests in helmet shells and hard ballistic configurations have shown that the new prepreg’s ballistic performance, under impact by bullets and bullet fragments, exceeds that of conventional PVB phenolic systems. Also, in accordance with STANAG 2920, Twaron PVB prepreg has been tested for temperature tolerance, showing little difference in the ballistic performance between armor plates stored at -20°C/-4°F, at 70°C/158°F and those stored at room temperature. Twaron PVB film has been designed for use with the same Twaron fabrics that are incorporated in existing protective equipment, including Twaron CT736, Twaron T750, Twaron T741 and Twaron T734.
Editor PickRoller-coater for prepreg production
Cygnet Texkimp Ltd. (Cheshire, UK) has revealed it is developing a high-tolerance reverse roll-coating machine to create sub-10-gsm films for the production of aerospace-quality prepreg.