Synthesis and properties of novel phosphorus‐containing thermotropic liquid crystalline copoly(ester imide)s

摘要: A series of novel phosphorus-containing polyesterimides were prepared from diols—a mixture a new aromatic bisphenol, namely 1,4-bis[N-(4-hydroxyphenyl)phthalimidyl-5-carboxylate]-2-(6-oxido-6H-dibenz oxaphosphorin-6-yl)-naphtalene, with aliphatic diols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 1,12—dodecanediol—and an diacid chloride containing two preformed ester groups, terephthaloyl-bis-(4-oxibenzoyl-chloride), via high-temperature polycondensation in o-dichlorobenzene. The structures monomers polymers verified by means Fourier transform infrared (FTIR) spectroscopy 1 H NMR spectroscopy. molar ratio bisphenol to diol was varied generate copolyesterimides tailored physicochemical properties, structure-properties relationships being established. effect the phosphorus content on thermal properties flame retardancy evaluated thermogravimetric analysis (TGA), TGA-FTIR, scanning electron microscopy. stable up 340 °C showing 5% weight loss range 340-395 10% 370-415 °C. char yields at 700 13.6-38% increasing bisphenol. liquid crystalline behavior investigated polarized light microscopy, differential calorimetry, X-ray diffraction. transition temperatures crystal melt 209-308