GB1269302A - Rubberised bitumen composition and process for making them - Google Patents

Abstract

1,269,302. Bituminous composition. W. R. GRACE & CO. 21 Aug., 1970 [22 Aug., 1969], No. 40398/70. Heading C3N. A bituminous composition comprises (1) a bitumen and (2) a curing agent which is an organic amine, and 1-15 parts by weight, per 100 parts by weight of the bitumen, of a liquid halogen-terminated butadiene or a reaction product of 1-15 parts by weight of the bitumen, of the polybutadiene and the organic amine. The polybutadiene is preferably terminated with allylic bromide groups. The amine catalyst is preferably an aliphatic tertiary polyamine and amine catalysts specifically used are N,N,N<SP>1</SP>,N<SP>1</SP>,N<SP>11</SP>,N<SP>11</SP> - hexamethyl triethylene tetramine and a polyamide resin. Suitable bitumens are native asphalts, pyrogeneous asphalts and pitches, petroleum asphalts, coal tar pitch and resins derived from the cracking of naphtha to form ethylenic materials. The bitumen may be diluted with a hydrocarbon oil before mixing with the rubber, preferably in the proportion 20-50 parts by weight oil to 50-80 parts by weight bitumen. The bituminous composition of the invention may be produced by mixing the bitumen in the liquid state with the polybutadiene, and then adding the curing agent. The mixture may be heated to accelerate the curing by the curing agent whilst suitably the amount of curing agent added is less than that required to cure completely the liquid halogen-terminated polybutadiene.