abstract |
FIELD: chemistry. n SUBSTANCE: aqueous polymer dispersion for vibration damping comprises a film-forming polymer in the form of dispersed particles comprising polymer phase C1 and other polymer phases P2 and P3; wherein polymer dispersion is obtained by free-radical emulsion polymerization comprising the following steps: (a) polymerization of the first monomer M1 loading to obtain polymer phase P1, followed by (b) polymerization of the second monomer M2 loading in the presence of P1 to obtain polymer phase P2, (c) polymerization of the third monomer M3 loading in the presence of P1 and P2, to obtain polymer phase P3, wherein the glass transition temperature difference between P1 and P2 is at least 20°C; the glass transition temperature difference between P2 and P3 is at least 5°C, and a chain-transfer agent is used for M1, M2 and M3 loading polymerization. A composition for essentially defect-free coating is claimed as well. n EFFECT: coating for vibration damping has a good appearance without blistering. n 21 cl, 3 tbl |