Starch solid composition containing thermoplastic expanded hollow particles and its use in topical application

摘要

In a solid expanded compsn., the matrix consists of acellular network formed from a prod. rich in starch and contg. hollow, thermoplastic, expanded particles of a (co)polymer from ethylenically unsatd. monomer(s). Pref. the matrix forms 70-98 wt.% of the compsn., and the prod. rich in starch is a cereal or potato flour, pure starch, starch modified w.r.t. the amylose/amylopectin level, cross-linked starch or starch modified by a functional gp. The particles are formed from monomers comprising (meth)acrylic acid esters, vinylidene chloride, acrylonitrile, styrene or derivs., or butadiene or derivs., and are esp. methyl (meth)acrylate (co)polymers, styrene-acrylonitrile copolymers, or copolymers of vinylidene chloride with acrylonitrile or vinyl chloride. Esp., the copolymer contains 0-60% of vinylidene chloride, 20-90% of acrylonitrile and 0-50% of an acrylic or styrenic monomer, partic. a vinylidene chloride-acrylonitrile copolymer or a vinylidene chloride-acrylonitrile-methyl methacrylate terpolymer. The particles have grain size 1-100 microns and density 15-200 kg/m<3>, and form 2-30% of the compsn.