Barium sulfate high reflectance materials used for polymer weatherability studies

Abstract

Stable white ultraviolet reflecting materials are necessary for studies of polymer weatherability. It was found that barium sulfate aqueous paste containing 30% water manufactured for X-ray contrast media is adequate for these purposes. Water was evaporated slowly and formed cracks were pushed off carefully, then considerably hard blocks having excellent optical properties were obtained. Poly (vinyl alcohol) having mass average degree of polymerization 2400 and containing 1.2 mol% residual vinyl acetate was used as binder. About 0.2% binder was found to be sufficient for obtaining enough flexural strength.