TECASON® S Plate

TECASON® S is unfilled polysulphone (PSU), a translucent light yellow amorphous engineering plastic bought above all for one property: very high hydrolysis resistance, which makes it suitable for repeated steam sterilisation. Ensinger lists it as autoclavable and positions it as a good alternative to polycarbonate, and that is where it earns its price. Tensile strength is 11,800 psi at break on a 375,000 psi tensile modulus, flexural strength is 18,500 psi, elongation at break is 50% and Izod impact is 1.3 ft-lb/in. Heat deflection temperature is 345°F at 264 psi, long-term service is 285°F with 340°F intermittent, and the glass transition temperature is 365°F. Being amorphous, it has no melting point.

It is machined into autoclavable instrument components, manifolds, trays, inspection windows, valve spools, flanges, pump housings, connectors, coil bodies, high-frequency insulators and lamp sockets for medical, pharmaceutical, semiconductor, electronics and food processing work. It insulates well, at 425 V/mil dielectric strength and a dielectric constant of 3.1 at 60 Hz, takes up only 0.30% water in 24 hours, and Ensinger rates it UL 94 V-0. The limitations are specific and worth respecting: polysulphone is prone to environmental stress cracking and its resistance to some hydrocarbons is limited, so keep solvents and aggressive cutting fluids away from loaded parts, and Ensinger rates its weathering resistance poorly, so keep it out of sustained outdoor exposure.