| 摘要 |
A pigmentable low profile thermosetting moulding material for prodn. of moulded articles with practically zero mould shrinkage or expansion, comprising (by wt.) 15-45 % of a thermosetting resin, 0.2-1 % catalyst, 3-15 % of a (meth)acrylic polymer powder with a particle size of less than 150 mu m, 3-60 % mineral fillers, 0-5 % (in)organic pigments and up to 60 % reinforcing fibres. The thermosetting resin is pref. an unsaturated polyester resin based on maleic acid, maleic anhydride or fumaric acid and at least one diol. The polyester may also contain units derived from aromatic-, satd. cycloaliphatic- or satd. aliphatic diacids or anhydrides. The (meth)acrylic polymer powder is pref. a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate with an alkyl acrylate with a 1-4 C alkyl gp. or a vinyl monomer. The catalyst is an organic peroxide. The mineral filler is chosen eg from CaCO3 and hydrated alumina. The reinforcing fibres are e.g. of glass, carbon or aramid. The pigment may be organic or inorganic and may be conductive, eg carbon black, to impart antistatic properties to moulded prods. |
