GB1353634A - Self-stabilized organosol systems comprising graft copolymers - Google Patents

Abstract

1353634 Graft polymers E I DU PONT DE NEMOURS & CO 19 April 1971 [28 Jan 1970 16 Dec 1970] 20583/71 Heading C3G A stable organo sol containing a film-forming graft copolymer (A-B) in an organic liquid (L) is made by (1) forming polymer (A) having the structure a-b in an organic liquid in which (A) is soluble, by addition polymerizing monomers (a) and (b), where #50% wt. of (a) consists of esters of acrylic, methacrylic, or ethacrylic acid, any balance of (a) being other ethylenically unsaturated monomers free from grafting sites activatable during step (2), and where the (b) units of (A) are activatable to grafting sites during step (2); (2) forming a graft polymer (A-B), by activating the (B) sites on (A) and additionpolymerizing thereto monomers (M) which would, if addition-polymerized by themselves, form a polymer (B), both (B) and (A-B) being soluble in the liquid in which (2) takes place, and (A) and (B) being such that one is and the other is not soluble in organic liquid (L); and (3) mixing the reaction product from (2) with a sufficient quantity of organic liquid of lower solvency power than the organic liquid in which (1) and (2) take place to form a stable organo sol. Monomers (M) may be the same as the (a) esters, and the (b) units may be where X is -COO- (the C- atom being attached directly to (A)), -O-, or -CO-; Y is -CH 3 or -C 2 H 5 , and Z is where R 2 and R 3 are Y, -CH 2 -NR 4 R 5 , -CH 2 CH 2 NR 4 R 5 where R 4 and R 5 are H or C 1-4 alkyl, or -CH 2 CH 2 OR 6 where R 6 is C 1-4 alkyl, or provided that when X is -CO-, Z can also be -NH-CH 2 -CH = CH 2 , and further that -X-Z can be e.g. allyl and/or diethylaminoethyl methacrylate. The other monomers forming the balance of (a) may be acrylic or methacrylic acid or their amides or nitriles, vinylacetate, styrene, α - methylstyrene, vinyl toluene, or 3 - (2 - methacryloxyethyl) - 2,2 - spirocyclohexyloxazolidine. Whichever of (A) or (B) is insoluble in the final organosol may have number av. M.W. 10,000-450,000, and the other, 2000-50,000. Steps (1) and (2) may take place in one or more ester, ketone, and/or aromatic hydrocarbon. (A) and (B) may have a solubility parameter difference of at least 0À5 parameter unit. The organic liquid (L) of the final stable organosol may be a mixture of (i) a poor solvent or poor solvent mixture for the film-forming polymer having mean b.p. 60-200‹ C., and (ii) a good solvent or good solvent mixture for the film-forming polymer having mean b.p. 80-320‹ C.; (ii) being less volatile than (i), and (ii)/(i) wt.-ratio being 40/60 to 70/30. The (b) units may be free of α,#-ethylenic unsaturation between those carbon atoms of (b) which reside in the backbone of (A); and the reaction of step (2) may take place in the organic liquid in which the reaction of step (1) was carried out, e.g. without removing any of the unreacted monomers after step (1). The stable organosol may contain graft polymer (A-B), polymer (A), and polymer (B). Also present may be a plasticizer or a pigment.