GB1309829A - Moulding compositions based on bitumen and an olefin polymer - Google Patents

Abstract

1309829 Bituminous/polyolefine composition BADISCHE ANILIN- & SODA-FABRIK AG 14 Aug 1970 [16 Aug 1969] 39194/70 Headings C3N and C3P A moulding composition comprises (a) 10-90 parts by weight of bitumen, (b) 90-10 parts by weight of an olefin polymer; and (c) 1-10 parts by weight of sulphur; the sum of (a), (b) and (c) amounting to 100 parts by weight. The amount of sulphur used is preferably 1-10% by weight, more preferably 3-6%, based on the total weight of components (a) and (b). The moulding compositions may be formed into shaped articles and the presence of the sulphur prevents such articles from sticking together when stored for a prolonged period under pressure. The sulphur may be present on the surface of the granules of the bitumen-olefin polymer mixture. The moulding composition may be prepared by mixing the components at temperatures of 100‹ to 200‹ C., preferably 120-160‹ C. Particularly suitable olefin polymers are homopolymers of ethylene, propylene, isobutylene and butene-1, copolymers of ethylene with butene-1, 1 or copolymers of ethylene with other copolymerizable ethylenically unsaturated compounds such as acrylic and methacrylic acid esters derived from C 1-8 alcohols, wherein the copolymer contains at least 50% by weight ethylene units, e.g. copolymer of 82% ethylene and 18% n-butyl acrylate. Mixtures of olefin polymers may be used and the use of a terpolymer of ethylene, an acrylic ester and acrylic acid is also envisaged. The weight ratio of ingredients (a) to (b) is preferably 2 : 3 to 3 : 2. The bitumen may be any natural or synthetic bitumen as well as asphalt and tar. A particular suitable bitumen has a penetration of 1-200 dmm. and a softening point of 140‹ to 40‹ C. The moulding composition may also contain 5-50% by weight, based on the total weight of (a) and (b), of one or more conventional fillers such as slate powder, limestone powder, gypsum, chalk, calcium silicate, talcum, asbestos, glass powder, rock wool, slag wool, aluminas, dolomite powder, stone powder, titanium dioxide, sawdust or ground cork. The moulding compositions may be processed into shaped articles such as sheets by the use of extruders, injection moulding machines and presses. The tensile strengths and elongations at break of these sheets are specified.