GB1378961A - Thermoplastic bituminous compositions - Google Patents

Abstract

1378961 Bituminous composition containing polybutene oils CHEMISCHE WERKE HULS AG 15 March 1972 [17 March 1971] 11966/72 Headings C3N and C3P A thermoplastic bituminous composition contains a polybutene oil consisting predominantly on a weight basis of polymerized nbutene(s) and having an average molecular weight of 200-2000, said polybutene oil being present in an amount up to 50% by weight, based on the weight of the composition. The bitumen preferably has a softening point of 25-180‹ C., a brittle point of at the lowest -25‹ C., and a depth of penetration of 400-2 1/10 mm. The bitumen may be pre-treated at 60-140‹ C. ' without blowing with 0À5-10% by weight of one or more materials selected from inorganic acids, acid-acting derivatives thereof, sulphur and organometallic compounds. Bitumens which are modified by solid polybutene-1 or polypropylene or solid copolymers of butene-1 with ethylene, propylene or hexene-1 or of propylene with ethylene, butene-1 or hexene may be used as may bitumens obtained by polymerizing an α-olefin containing at least 3 carbon atoms in the presence of bitumen. The polybutene oil may be prepared by polymerization of one or more n-butenes with a Friedel Crafts catalyst in the liquid phase at - 70‹ to +100‹ C. or by polymerizing one or more nbutenes in the liquid phase by means of a carrier-free Friedel-Crafts catalyst in the presence of a diene and/or acetylene. The thermoplastic bituminous composition may be prepared by simple mixing or by polymerizing 5-200 parts by weight of n-butene or of a C 4 -cracked gas cut containing n-butene with the aid of a Friedel-Crafts catalyst at -50‹ to +100‹ C. in the presence of 50-100 parts by weight of bitumen. The examples refer to compositions containing 3%, 10% and 50% of the polybutene oil.