Cationic polymerization with boron halides. V. Synthesis of poly(isobutylene‐b‐styrene) and poly(styrene‐b‐isobutylene)
- 1 January 1978
- journal article
- research article
- Published by Wiley in Journal of Polymer Science: Polymer Chemistry Edition
- Vol. 16 (1) , 243-259
- https://doi.org/10.1002/pol.1978.170160123
Abstract
Block copolymers of isobutylene and styrene, PIB‐b‐PSt and PSt‐b‐PIB, have been prepared by a two‐step synthesis involving (1) preparation of terminally chlorinated (telechelic) polyisobutylene or polystyrene “prepolymers” by using the H2O/BCl3 initiator system and (2) blocking from these telechelic prepolymers a second polymer segment by using an alkyaluminum, e.g., Et2AlCl coinitiator. The telechelic polyisobutylene and polystyrene contain tertiary and benzylic chlorine termini, respectively. Block copolymer characterization included detailed selective solvent extraction procedures, coupled with GPC determinations, PMR, solubility, and intrinsic viscosity studies. The synthesis of PIB‐b‐PSt and PSt‐b‐PIB provides direct chemical evidence for the presence and position of active chlorine termini in BCl3‐coinitiated olefin polymerizations.Keywords
This publication has 4 references indexed in Scilit:
- Block and graft copolymers by selective cationic initiation. IV. Physical properties of bigraft copolymersJournal of Polymer Science: Polymer Chemistry Edition, 1975
- Block and Bigraft copolymers by Carbocation PolymerizaationJournal of Macromolecular Science: Part A - Chemistry, 1975
- Cationic Polymerizations at Ultralow TemperaturesPublished by American Chemical Society (ACS) ,1962
- Steric Strains as a Factor in the Solvolytic Reactions of Neopentyldimethyl and Dineopentylmethylcarbinyl Chlorides1,2Journal of the American Chemical Society, 1953