COPOLYMER BASED ON VINYLACETATE AND BUTYLACRYLATE EMPLOYED AS POLYMERIC BASE FOR VIBRATION-ABSORBING MATERIAL AND PROCESS FOR MANUFACTURING SAME Russian patent published in 1994 - IPC

FIELD: chemistry and chemical industry. SUBSTANCE: copolymer based on vinylacetate, butylacrylate and 1-methacryloyloxy- 1-tert-butylperoxyethane can be used as polymeric base in manufacture of vibration-absorbing material. It is novel species of chemically prepared polymers. This copolymer has inherent viscosity in acetone at temperature of 20 C (0.42 to 1.60 dl/g) and includes following in its structure, namely: 60.9 to 70.5 mole percent vinylacetate, 27.5 to 37.1 mole percent butylacrylate and 0.8 to 4.8 mole percent 1-methacryloyloxy-1-tert-butylperoxyethane. Process used for manufacture of this copolymer is of water-emulsion type and prescribes using sodium salts of sulfatized alkylphenol ethers as surfactant to be taken in amount of 0.8 to 6.3 percent by total mass of copolymers. Process involves water-soluble initiator to be introduced by six passes in equal portions every 24 to 48 min. Copolymer admixture includes following ingredients: 64.0 to 73.4 mole percent vinylacetate, 24.6 to 34.0 mole percent butylacrylate and 0.8 to 4.8 mole percent 1-methacryloyloxy-1-tert-butylperoxyethane. Disclosed process further prescribes that admixture of monomers be injected into reaction zone at rate of 25.0 to 50.0 percent of total charge per 1 h. EFFECT: this process allows producing polymer possessing excellent rheological properties, readily extrudable and reprocessable into film; resultant copolymer perfectly withstands static loads and cannot be squeezed out of standard "sandwich" vibration-absorbing material in service; new vibration-absorbing material has excellent modulus of elasticity. 3 cl, 2 tbl