Abstract
Mechanism of polymerization reactions forming the precursor polymers of poly(p-phenylenevinylene) (PPV) and its heteroaromatic derivatives are summarized. Reactions of α,α′-bis(tetrahydrothiophenio)-p-xylene dichloride with OH- in H2O proceed via 1,6-elimination-free radical polymerization mechanism. The rate of elimination reaction increased and that of subsequent polymerization decreased as the aromatic moiety was changed from phenyl to thienyl to furyl. Also, the elimination reaction mechanism changed from (E1cb)R to (E1cb)irr for the same variation of the aromatic moiety, whereas the polymerization mechanism remained the same. The polymerization mechanism for the Gilch route was proposed to be ionic. However, it might actually proceed by a free radical mechanism. The mechanism of the polymerization pathway of the sulfo(i)nyl route changed from a free radical to a competing ionic and free radical by the change in the solvent from protic to aprotic. The thermal decomposition of the bis-sulfonium salts proceeds by the SN2 displacement of the tetrahydrothiophene by chloride followed by the thermal elimination of HCl. On the other hand, the elimination of the sulfi(o)nyl group is considered to proceed via a syn-elimination.
Original language | English |
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Pages (from-to) | 307-355 |
Number of pages | 49 |
Journal | Progress in Polymer Science (Oxford) |
Volume | 27 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2002 Mar |
Bibliographical note
Funding Information:The author is indebted to the students and collaborators whose names appear in the joint publications listed herein. This work was supported by KOSEF (Project 995-0300-001-2) and a NRL grant from MOST and CRM-KOSEF.
Keywords
- Elimination
- Free radical mechanism
- Gilch route
- Mechanism
- Poly(2,5-furanovinylene)
- Poly(2,5-thienylene vinylene)
- Poly(p-phenylenevinylene)
- Precursor route
- Sulfi(o)nyl route
- Thermal elimination
ASJC Scopus subject areas
- Ceramics and Composites
- Surfaces and Interfaces
- Polymers and Plastics
- Organic Chemistry
- Materials Chemistry