GB1166880A - Improvements in or relating to Colloidally Dispersable Alpha-Olefin Copolymers - Google Patents

Abstract

1,166,880. Coating. HERCULES Inc. 29 Dec., 1967 [13 Nov., 1967 (2); 25 Aug., 1967], No. 59172/67. Headings B2E and B2K. [Also in Divisions B5 and C3] Substrates may be coated by applying thereto colloidal dispersions of copolymers of a first olefin selected from ethylene, butene-1, pentene-1, 3-methyl butene-1, hexene-1, 4- methylpentene-1 and styrene and 2 to 25 mole per cent of a second α-olefin having 2 to 20 carbon atoms or a styrene, the copolymer having (I) an average primary particle size of 0.02 to 0.5 micron with 75 per cent of said particles being in the range 0.1 to 0.4 micron, said primary particles existing as discrete particles and reversible clusters thereof essentially free from irreversible agglomerates having a particle size greater than 5 microns, (2) at least 50 per cent insolubility in decahydronaphth.alene, (3) a crystallinity of less than 90 per cent of the inherent crystallinity of a homopolymer of the monomer present in major proportion, and being (4) colloidally dispersible in a liquid non-solvent to form a stable dispersion free from irreversible clusters of primary particles larger than 5 microns; and heating to fuse the polymer particles. Specified substrates are metal sheets and wires, paper, wood, fabrics of natural and synthetic fibres, plastics and glass. Metals are preferably primed, e.g. with maleic anhydride modified polypropylene, or such may be incorporated in the coating compositions, which may also include pigments, antioxidants and stabilisers. Examples describe air-knife-coating of (11) steel panels and (14) maple plywood panels and rod coating of (16) offset printing paper with compositions comprising dispersions of ethylene/propylene copolymers and titanium dioxide in heptane and high boiling petroleum fractions; dip-coating (12 and 13) copper wires and air-knife-coating (15) maleic anhydride modified polypropylene primed steel panels with compositions comprising ethylene/propylene copolymers, 4, 4'- butylidene bis (2-t. butyl 5-methylphenol), diphenyl octyl phosphite, distearyl thiodipropionate and heptane; and air-knife-coating of stainless steel panels with compositions comprising a 3-methyl butene-1 /octene-1 copolymer, maleic anhydride modified polypropylene and hexane.