Process for the preparation of copolymers of ethylene-vinyl acetate emulsion polymerization

摘要

Process for the preparation of copolymers of vinyl acetate-ethylene by polymerization enemulsión radically initiated vinyl acetate and 18 to 34% by weight of ethylene, based on total weight of losmonómeros vinyl acetate and ethylene and optionally other comonomers, wherein the presence of at least one protective colloid and from 0.5 to 4% by weight polimerizaen, based on the total amount of monomers, of at least one nonionic ethoxylated emulsifier with an alkyl branched or unbranched or decopolímeros form ethylene oxide-propylene oxide and under the exclusion of chain regulators, disponiéndosepreviamente before the start of polymerization 10 to 70% by weight of vinyl acetate monomer and 40 to 100% by weight of ethylene monomer, prearranging the proportion of protective colloid to 100% by weight, prearranging the proportion of emulsifier in at least 25% by weight and metered time providing ciónlas remaining proportions of monomers, emulsifier and protective colloid during the polymerization, so that the proceeding process criterion COP ( "criterion of process") 2.5 COP 70, where it holds that COP = 100 x met (ETM2,5 ETV1,25 x x x EA2,5 EV1,5 x VV-1), with ETM = MEt / MM, ETV = METV / MEt, EA = 100 ME / MM, EV = MEV / ME and VV = MVacV / MVAC with MEt = total mass of ethylene in kg, MM = total mass of monomer in kg, METV = mass preload deetileno in kg, ME = total mass of emulsifier kg; MEV = mass preloading kg emulsifier; MVacV = mass preloading vinylacetate kg and MVAC = total mass of vinyl acetate in kg.