| 摘要 |
A continuous process for solution polymerizing an olefinic compound of the formula CH2 = CHR, wherein R is hydrogen or an alkyl, aryl, cycloalkyl or haloaryl radical containing not more than 12 carbon atoms comprises polymerizing a stirred reaction mixture at a temperature just above the precipitation temperature of the polymer and controlling the monomer concentration in the reactor. Polymers exemplified are homopolymers of propylene, butene-1, n-pentene-1, 3-methyl-butene-1, and n-octene-1; copolymers of propylene with ethylene, styrene, butadiene, and vinyl cyclohexane; and copolymers of butene-1 with p-methyl styrene, and n-pentene-1 with p-chloro styrene. Catalysts exemplified are: the reaction product of titanium trichloride, aluminium triethyl, thiocresol and lithium triethanolamine; TiCl4 + Al(C2H5)3; TiCl3 + Al triisobutyl; ZrCl4 + Al(C2H5)3; ZrCl3 + Al tributyl; n-butyl Li; LiAl(C2H5)4; and TiCl4 + Ti metal. Many other monomers and catalysts are specified. Suitable solvents are xylene or mixed octanes. The polymers produced have a high isotactic content. The polymerization is effected in a reactor under isothermal and essentially adiabatic conditions. The temperature of the reactor is automatically controlled by simultaneously varying the monomer and solvent feed rates while maintaining the ratio of the two. The monomer concentration in the reactor is varied by adjusting the monomer/solvent feed ratio. A flow diagram is given. |
