| 摘要 |
PURPOSE:To obtain the title composition improved in redispersibility, handleability and the properties of a composition containing the same by drying a composition comprising a specified aqueous dispersion and a formalin condensate of a melamine sulfonate and grinding the dried product into a powder. CONSTITUTION:An aqueous dispersion of a polymer of a glass transition temperature <=30 deg.C is obtained by emulsion-polymerizing an alpha,beta-ethylenically unsaturated monomer at 0-100 deg.C under a pressure <=100kg/cm<2> in the presence of, optionally, an emulsifier, a protective colloid, a polymerization initiator, etc. Separately, an amine based on melamine is reacted with formaldehyde and a sulfite for 0.5-6hr at 60-80 deg.C and a pH>=10 in an aqueous medium and further reacted for 1-15hr at 20-70 deg.C and a pH of 3.5-6.5 to obtain a reaction mixture, and the pH of this mixture is adjusted to 7-13 to obtain a formalin condensate of melamine sulfonate of a weight-average MW>=100000. A composition obtained by mixing the dispersion with the condensate in a solid weight ratio of (75-99); (25-1) is dried and ground into a powder. |
