Patent ID: 7273906
Filing Date: 2007-09-25
Classification: A61B,C08F,C08L

Abstract:
1. A process for making a dip-forming latex which comprises the steps of: copolymerizing 50 to 89.5 parts by weight of a conjugated diene monomer, 10 to 40 parts by weight of an ethylenically unsaturated nitrile monomer, 0.5 to 10 parts by weight of an ethylenically unsaturated acid monomer and 0 to 20 parts by weight of other copolymerizable ethylenicahy unsaturated monomer, provided that the total of these monomers is 100 parts by weight, by initiating said copolymerization with a monomer mixture comprising at least 90% by weight of the amount of conjugated diene monomer used, 55 to 85% by weight of the amount of ethylenically unsaturated nitrile monomer used, 50 to 85% by weight of the amount of ethylenically unsaturated acid monomer used and at least 90% by weight of the amount of other copolymerizable ethylenically unsaturated monomer used, and thereafter, adding the remainder of ethylenically unsaturated nitrile monomer while the polymerization conversion of the ethylenically unsaturated nitrile monomer is within a range of 40 to 95%, adding the remainder of ethylenicatly unsaturated acid monomer while the polymerization conversion of the total monomers added is within a range of 20 to 80%, and adding the remainders of conjugated diene monomer and other copolymerizable ethylenically unsaturated monomer at any time before the termination of copolymerization, to continue copolymerization.