Method for preparing carboxylated NBR latex

Abstract

The invention relates to a method preparing carboxylic butyronitrile-butadiene, its components comprise deionized water, emulsifying agents, molecular weight regulating agents, PH regulating agents, peroxodisulfate free initiator, butadiene monomers, acrylic nitrile, unsaturated carboxylic acid and unsaturated carboxylic ester, and the process comprises: adding the said components in a percentage by weight of 90-140 % of deionized water, 2.2-3.6 % of emulsifying agents, 0.5-1.5 % molecular weight regulating agents, 0.2-0.5 % of PH regulating agents and 0.3-1.1 % of peroxodisulfate free initiator into a polymeric reactor, then adding the butadiene monomers in a percentage of 52-58 % into the polymeric reactor and stirring to homogeneously mix, increasing the temperature to 40-50 Deg. C, and in the press of 0.3-0.5 MPa, continuously adding the mixture in a percentage of acrylic nitrile of 30-45 %, unsaturated carboxylic acid of 0.5-8 % and unsaturated carboxylic ester of 0.5-7.5 % using a dosage pump, the adding time lasts 6-12 h, and reacting to 2-4 h, then stop, degassing in a degassing tank and second degassing in a degassing column, regulating the latex treated from the degassing column by PH regulating agents to get the completed product.

Description

1. Technical field [0001] The invention discloses a preparation method for producing carboxylated nitrile latex, in particular the process improvement of the continuous addition of highly active polymerized monomers in the reaction process and the removal of residual acrylonitrile monomers in products. 2. Background technology [0002] Compared with natural rubber latex, carboxylated nitrile latex has its unique advantages. Because of the introduction of carboxyl (-COOH) and nitrile (-CN), the dipped products made of carboxylated nitrile latex have excellent oil resistance, film-forming properties and The tensile strength and other properties have been greatly improved. At present, the production method of carboxylated nitrile latex in the world mainly adopts the emulsion polymerization method, and companies in countries and regions such as Taiwan Nandi, Japan Zeon, Germany Bayer, and the United States all adopt this method. Production. In addition to butadiene and acrylon...

AI Technical Summary

Problems solved by technology

The continuous addition of monomers with high reactivity overcomes the shortcoming that these monomers are prone to violent polymerization when they are added completely at one time, so that the production process is more stable and safe. At the same time, it also overcomes the quality of the products produced by adding these monomers at one time. Inhomogeneous shortcoming; The present invention adopts two-step degassing method when latex degassing, and the use of efficient degassing tower can reduce the content of residual monomer wherein more, so just in order to reduce residual monomer in finished product latex to Hazards to humans and the environment

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