The polymerisation of styrene by solid catalysts derived from the reaction of titanium IV compounds with grignard reagents
1959; Wiley; Volume: 32; Issue: 1 Linguagem: Inglês
10.1002/macp.1959.020320115
ISSN0025-116X
Autores Tópico(s)Polyoxometalates: Synthesis and Applications
ResumoAbstract Solid catalysts, prepared by treating alkyl or aryl magnesium halides with titanium tetrachloride or butyl o‐titanate, polymerize styrene rapidly to amorphous low molecular weight (10 4 –10 5 ) polymer. The energy of activation for the process is approximately 20 kcal/mole for all active catalysts. Kinetic evidence indicates that initiation and propagation proceed by insertion of monomer molecules at a metal‐carbon bond and that termination is spontaneous. If the catalysts are pre‐heated to 150°C., the polymer produced contains a substantial proportion of high molecular weight (ca. 5·10 6 ) crystalline material.
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