摘要: This report covers the first year of work on the program to develop new, high temperature stable, transparent plastics for use in high performance aircraft as materials of construction for windshields and/or canopies. Thirty novel... 展开 This report covers the first year of work on the program to develop new, high temperature stable, transparent plastics for use in high performance aircraft as materials of construction for windshields and/or canopies. Thirty novel materials were prepared during this period, each with a glass transition temperature exceeding those of currently used acrylic and polycarbonate plastics, and possessing varying degrees of transparency, color, and impact strength. Substitution of thermally stable, aromatic diols and diacids by appropriate techniques for bisphenol-A in established preparatory procedures for polycarbonates and polyesters has resulted in the more thermally stable materials. Depending upon the reactants involved, new polyesters, polycarbonates, polyester carbonates, copolyesters and copolyester carbonates have been prepared. Materials based upon tetramethyl dicumyl bisphenol (coded AF-TP-2) have glass transition temperatures (Tg) ranging from 190 to 228 degrees C (374 degrees F to 442 degrees F); light transmittance is generally over 80%; however, haze is rather high, the yellowness index is high, and the impact strength (notched izod) is between 1.0 to 3.0 ft-lb per inch of notch. Materials based upon combinations of tetramethyl dicumyl bisphenol, bisphenol-A, tetraphthoyl chloride and phosgene also possess desirable properties. Properties of many of the materials have been determined while others are still in progress. (Author) 收起