Synthesis and properties of polyesters based on substituted bisphenols

Aromatic polyesters, based on substituted biphenols and bisphenols and a number of aliphatic diacids and terephthalic/isophthalic acid mixtures, have been synthesized. The syntheses of the biphenols were accomplished by oxidative tail-tail coupling of the corresponding phenols, followed by reduction of the diphenoquinones obtained. Bisphenols were synthesized by conventional methods. A new bisphenol was obtained by reacting 2,6-diphenylphenol and formaldehyde. The polymers investigated have glass transition temperatures (T g ) ranging up to 225°. The polymers are difficult to crystalize thermally. Their resistance to hydrolysis is excellent. In general, however, oxidative- and u.v.-stabilities are quite poor.