| 摘要 |
<p>The compsns. are prepd. by mixing together at 120-230 degrees C with stirrine, (a) 80-98% of a bitumen of 30-220 penetration, and (b) 2-20% of a polysequencrol copolymer of average mol.wt. 30000-300000 of the styrene-conjugated diene type, for at least 2 hrs. and then (c) adding 0.1-3% S w.r.t. (a) under the above conditions of temp. and stirring for at least 20 mins. (b) is selected such that the conjugated diene sequence is a carboxylated butadiene or isoprene. Used for road and industrial coating, eg. asphaltic covering, sealing, rooling, paints, cars, and for thermal electrical and sound insulation. The in situ vulcanisation obtd. with these polymers gives products having improved elastomeric props. in the cold and a viscosity, when hot, identical with that of a bitumen based on a disequenced. polystyrene polybutadiene copolymer (see FR7639233/76). The presence of S also reduces the amt. of these sequenched copolymers which must be added to the bituments-polymer compsn.</p> |
