Patent ID: 6489406
Filing Date: 2002-12-03
Classification: C08G,C08L

Abstract:
An unsaturated polyester resin which, when cured, is flexible and weather-resistant at a temperature below 0Â° C., wherein the unsaturated polyester resin comprises:1) a linear unsaturated polyester with a cone and plate viscosity (I.C.I.) of 2 poise/125Â° C.-20 poise/125Â° C. and a molecular weight Mw of 20,000-100,000, wherein the linear unsaturated polyester is obtained by reacting, in the presence of an inhibitor and of a metal catalyst, together: 5-30 mol % of one or more ethylenically unsaturated dicarboxylic acids (A) selected from the group consisting of maleic acid, maleic anhydride and fumaric acid, 20-45 mol % of one or more other aliphatic or aromatic acids (B) selected from the group consisting of phthalic acid, phthalic anhydride, isophthalic acid or terephthalic acid, and 40-60 mol % of two or more polyhydric alcohols (C) selected from the group consisting of triethylene glycol, dipropylene glycol, tripropylene glycol, Bisphenol A, trimethylol ethane, trimethylol propane, polyethylene glycol and derivatives thereof, polypropylene glycol derivatives thereof, polyethylene oxides, polypropylene oxides and trimethylol propane polymers wherein said polyhydric alcohols have an overall hydroxy functionality of 2 or 3 per molecule and a molecular weight of 400 to 1500, and the ratio of difunctional polyhydric alcohols to trifunctional polyhydric alcohols is 60-80 mol %: 20-40 mol %; and 2) 30-60 wt % of one or more reactive monomers; and that after curing the elongation at break of the cured product is 150-460% at 20Â° C. and 20-460% at âˆ’20Â° C.