PROCESS FOR PREPARING AQUEOUS POLYMER DISPERSIONS, AND THEIR USE

摘要

A process for the preparation of aqueous polymer dispersions comprising polymerizing vinyl esters and up to 50% by weight of the total monomer of compounds with unsaturated ethylenic bonds at a temperature of 10 DEG to 100 DEG C. in the presence of an at least partially water-soluble free-radical initiator and at least one starch member of the group consisting of cyanalkylated starch, hydroxyalkylated starch and carboxyalkylated starch and optionally present conventional adjuvants with the starting mixture containing not more than one-third of the total monomers and the remaining monomers being added by metering during the polymerization, the initiators being at least one member of the group consisting of hydrogen peroxide and organic hydroperoxides in an amount of at least 30 mmol per kg of total monomer mixture and optionally present water-soluble reducing agent and the amount of starch being at least 1% by weight based on the total monomer weight.