초록 ▼

This invention relates to stable, aqueous polymeric dispersions comprised of graft copolymers of at least one vinyl monomer and a derivatized and thinned amylopectin starch, that is, a starch wherein the starch is made up entirely or almost entirely of amylopectin units such as waxy maize starch. Th

This invention relates to stable, aqueous polymeric dispersions comprised of graft copolymers of at least one vinyl monomer and a derivatized and thinned amylopectin starch, that is, a starch wherein the starch is made up entirely or almost entirely of amylopectin units such as waxy maize starch. The amylopectin starch is derivatized to a degree of substitution of at least about 0.01 and thinned to an intrinsic viscosity of not less than about 0.12 deciliters per gram. The graft copolymers have a starch/monomer ratio of less than about 100/25 by weight. The dispersions have high solids contents (25% by weight or greater) and are stable (show no excessive increase in viscosity and remain homogeneous) over extended periods of time. This invention also relates to processes for the production of the dispersions.

대표청구항 ▼

A stable aqueous polymeric dispersion comprised of at least 25% solids by weight of a graft copolymer of at least one vinyl monomer and a derivatized and thinned amylopectin starch with a degree of substitution of at least about 0.01 and an intrinsic viscosity of not less than about 0.12 dl/g wherei

A stable aqueous polymeric dispersion comprised of at least 25% solids by weight of a graft copolymer of at least one vinyl monomer and a derivatized and thinned amylopectin starch with a degree of substitution of at least about 0.01 and an intrinsic viscosity of not less than about 0.12 dl/g wherein the starch/monomer ratio of the graft copolymer is less than about 100/25 by weight. The process for producing a stable aqueous polymeric dispersion comprised of at least 25% solids by weight of a starch graft copolymer of at least one vinyl monomer and a derivatized and thinned amylopectin starch which comprises forming a derivatized and thinned amylopectin starch with a degree of substitution of at least about 0.01 and an intrinsic viscosity of not less than about 0.12 dl/g and forming a graft copolymer of said derivatized and thinned starch and at least one vinyl monomer by means of an initiator which acts to initiate graft copolymerization onto the starch to the substantial exclusion of the initiation of homopolymerization or copolymerization of said vinyl monomer(s) and wherein the starch/monomer ratio of the thinned and derivatized starch to the vinyl monomer(s) is less than about 100/25 by weight.