IMPROVED REINFORCED POLYOXYMETHYLENE MOLDING COMPOSITION CAPABLE OF PRODUCING SYNTHETIC ARTICLE WITH IMPROVED PHYSICAL PROPERTIES

摘要

Fibre-reinforced polyoxymethylene moulding compsns., forming composite bodies having improved physical props., comprise a mixt. of (1) a polyoxymethylene type polymer; (2) 2-60%, pref. 5-50% (w.r.t. total compsn.) of fibrous reinforcement material, e.g. glass, asbestos, cellulose, graphite, and (3) 0.5-5%, pref. 1-3% (w.r.t. total compsn.) of a polycarbodiimide, and pref. an aromatic polycarbodiimide which is not sterically hindered and which is (a) derived from an aromatic isocyanate which is unsubstd. or is substd. by is not 1 Me gp. per aromatic ring, and (b) contains =3 carbodiimide units per mol. polycarbodiimide. The presence of a thermoplastic phenoxy resin of mol.wt. 15000-75000, pref. 20000-50000, in a wt. ratio of polycarbodiimide : phenoxy resin of 1:16-50:1, synergically improves the physical props. of the glass fibre-reinforced compsns. The combination of (3) and (4) appears to increase the adhesion between the chemical function(s) of the oxymethylene polymer chain and the fibrous reinforcement. The prepared articles have increased impact resistance and tensile strength.