F. M. Coutinho, Thais H. S. Costa, L. Maria
Jun 1, 1992
Citations
0
Influential Citations
4
Citations
Journal
European Polymer Journal
Abstract
Abstract The role of ethers in the synthesis of a highly active and stereospecific catalyst for propylene polymerization has been investigated. Diisoamyl ether (DIAE) and tetrahydrofuran (THF) were employed as electron-donors in the β-TiCl 3 treatment during the three-step synthesis. Dibutyl ether (DBE) was used as a first internal base complexed with TiCl 4 and Et 2 ClAl (DEAC) in iso-octane solution in the one-step synthesis. While the use of DIAE and THF in the three-step synthesis has mainly led to the formation of λ-TiCl 3 , the use of DBE in the one-step synthesis has led to the formation of a highly active and stereospecific δ-TiCl 3 . The effects of ethyl benzoate, tributyl phosphate and diisobutyl phthalate as second internal bases on the crystalline modification, activity and stereospecificity of TiCl 3 have also been studied. Possible causes for the formation of different TiCl 3 crystalline structures are discussed through comparison of both routes of TiCl 3 synthesis.