| 摘要 |
A low viscosity unsaturated polyester resin for making glass fiber reinforced products is described, which comprises an alkyd prepared by esterification of maleic anhydride and/or acid and/or fumaric acid, optionally together with phthalic anhydride and/or acid, with one or more glycols, essentially comprising dipropylene glycol, and further comprises 27-34% by weight (of the total resin) of an ethylenically unsaturated monomer copolymerizable with the alkyd, essentially chosen among styrene and vinyl toluene, the alkyd having a molecular weight/double bond factor between 200 and 360 and an amount of free functional groups between 80 and 100 mg of KOH per g of alkyd inclusive. The products obtainable from said resin by conventional processing techniques are also described. The low viscosity of the resin results in better workability and better behavior of the resin during molding while the mechanical properties of the finished products are very good. |
