Patent ID: 8562850
Filing Date: 2013-10-22
Classification: C08F,C09D

Abstract:
1. An emulsion for vibration damping materials, comprising an acrylic emulsion obtainable by emulsion polymerization of a monomer component, wherein the emulsion is obtainable by emulsion polymerization using an anionic emulsifier and/or a reactive emulsifier, and particles of the acrylic emulsion have an average particle diameter of 100 to 450 nm, and the particles of the acrylic emulsion have a particle size distribution of 30% or less, where particle size distribution is defined as a value obtained by dividing a standard deviation by a volume average particle diameter thereof (standard deviation/volume average particle diameter×100), wherein the monomer component forming the particles of the acrylic emulsion contains 30 to 70% by weight of a styrene monomer relative to 100% by weight of the entire monomer component for forming the particles of the acrylic emulsion and wherein the total amount of acrylic hard monomer in the monomer component for forming the particles of the acrylic emulsion is 10% by weight or less relative to 100% by weight of the entire monomer component for forming the particles of the acrylic emulsion, wherein the acrylic hard monomer is methacrylic acid ester(s) each of which differs from all of the other acrylic monomers of the particles of the acrylic emulsion and wherein a homopolymer of each methacrylic acid ester present has a Tg that is 30° C. or more higher than the Tg of a polymer from all of the acrylic monomers other than the methacrylic acid ester(s), and wherein the particles of the acrylic emulsion each have a core part and a shell part and wherein the total amount of polymerized styrene monomer is 30 to 70% by weight of said particles of the acrylic emulsion having a core part and a shell part.