Halogen contg. unsaturated polyester resins - with improved hydrolysis resistance, contg. units derived. e.g. from tetrachloro-meta:xylylene bis-carbomethoxy-phenyl ether

摘要

Halogen contg. polyesters are of formula -(CO-R-CO-O-R'-O)- (I). In the formula, R is an organic gp. derived from satd. dicarboxylic acids and is comprised of 1-100% molar, pref. 100% or 2-10% molar, gps. (II) and/or gps. (III): and 0-99% molar, esp. 0% or 98-90% molar of phenylene and/or naphthylene and/or 3-10C (cyclo) alkylene gps.; R' is an organic gp. derived from a satd. dialcohol, comprising a straight or branched 2-10C (cyclo)-alkylene gp. and/or a gp. derived from an oligomeric hydroxylated alkylene terephthalate. Z is -C(CH3)2- or -SO2-; and X is H, Br or Cl. Part of the dicarboxylic acid component may be replaced by an unsatd. dicarboxylic acid component to give an unsatd. polyester resin which gives a resin soln. in a comonomer such as styrene which can be cured with peroxide curing agents. The resins have good flame retardant properties coupled with increased resistance to hydrolysis in acid or basic medium compared with prior art halogen contg. unsatd. polyester resins. Cured cast mouldings are colourless and transparent and the prods. have a high Martens temp. (dimensional stability under heating) and good mechanical properties.