| 摘要 |
a -Olefins of formula R-CH=CH2 in which R denotes a hydrocarbon radical containing at least two carbon atoms, are stereospecifically polymerized using a catalyst containing a monoalkyl aluminium dihalide, violet titanium trichloride and an ether of the formula R1-O-R2 in which R1 is alkyl or aralkyl and R2 is alkyl, aralkyl or aryl, the ether and the monoalkyl aluminium dihalide being employed in a molar ratio between 0.65: 1 and 2.5: 1. In the examples, butene-1 is homopolymerized or copolymerized with propylene, and 4-methyl pentene-1 is homopolymerized. Catalysts exemplified are mixtures of ethyl aluminium dichloride and violet titanium trichloride with diethyl ether or di(n-butyl)ether. Solvents used are heptane and petroleum ether. The reaction is terminated with methanol and hydrochloric acid or with water. The polymerization may be a batch, semi-continuous or continuous process. The polymers produced have a high isotactic content. |
