HEAT RESISTANT POLYMERS AND BLENDS OF HYDROQUINONE POLY(ISO-TEREPHTHALATES) CONTAINING RESIDUES OF p-HYDROXYBENZOIC ACID

摘要

This invention pertains to novel copolyesters consisting essentially of units (I), (II), (III), and (IV), and blends of these polymers and articles made from both. Units (I), (II), (III), and (IV) are present in specified proportions as defined in the description of the invention. The instant copolyesters display orientation in the molten state, good fiber ratings and high strength; they have melting points in the range of from about 340 to about 400 DEG C and are melt-processible. Advantageously, these compositions filled with about 30 weight percent of glass fibers display heat distortion temperatures of over 240 DEG C up to about 280 DEG C and higher, when measured under a load of 264 psi. When blended, certain properties are improved, particularly they are easier to melt-fabricate, have a decreased tendency to blister and increased strength. These polymers and blends may be used advantageously in ovenware, electronic components, electrical equipment, and other end uses requiring high temperatures.