ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Among the four 1,1-disubstituted 2-vinylcyclopropanes, diethyl 2-vinylcyclopropane-1,1-dicarboxylate (Ia), 2-vinylcyclopropane-1,1-dicarbonitrile (Ib), ethyl 1-cyano-2-vinylcyclopropanecarboxylate (Ic), and 1,1-diphenyl-2-vinylcyclopropane (Id), Ib and Ic polymerized well with sodium cyanide in N,N-dimethylformamide. Ib was most reactive and a polymer (IIb) from Ib exhibited an inherent viscosity of 1.05 dl/g (concentration of 1.0 g in 100 ml of 95% H2SO4). All experimental results indicated that the polymerization proceeded by ring opening and that the structure of the polymers had pendant vinyl groups. The polymer IIc from Ic was soluble in common solvents like acetone, but IIb was soluble only in 95% H2SO4. Reactions of those compounds with benzenethiolate ion in ethanol yielded addition products that supported the ring-opening polymerization of those monomers. In the postulated mechanism of polymerization cyanide ion attacks the carbon of a cyclopropane ring with electron-releasing vinyl group and the resulting anion is thereby stabilized by two electron-withdrawing substituents. The propagation takes place by the reaction of the anion with another monomer molecule.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1979.170171010
