ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Radical reactions initiated by chelate complexes of transition metals. VIII. System poly(vinyl chloride)-bis(-)ephedrine copper(II) chelate as initiator of vinyl polymerization

J. Bartoň and H.T. Dung

Polymer Institute, Slovak Academy of Sciences, 809 З4 Bratislava

Abstract: The system poly (vinyl chloride)—bis (-)ephedrine copper(II) chelate as initiator of n-butyl methacrylate pofymerization in cyclohexanone has been investigated. It has been found that with increasing monomer concentration the exponent value for [chelate] in the expression for polymerization rate decreases. Thus for [BuMc] = 0.78 and 3.14 mol^-1, the exponents are 0.23 and 0.17, respectively. The dependence of polymerization rate on monomer concentration suggests that the monomer does not participate in the initiation reaction, i.e. that the exponent for monomer concentration in the expression for polymerization rate equals one. From the data on polymerization rate of n-butyl methacrylate at various temperatures over the range 50 — 90°C the activation energy of 23.4 kcal mol^-1 has been calculated. It was found that under the conditions of [CI]Pvc/[chelate]  ≥1, the polymerization rate of n-butyl methacrylate was practically independent of poly (vinyl chloride) concentration. By a convenient choice of poly (vinyl chloride) and monomer concentration the initiation system investigated enables the preparation of reaction products of quite a high abundance of poly (vinyl chloride) component, i.e. either a grafted copolymer or practically pure homopolymer of poly(n-butyl methacrylate), in which the concentration of the poly (vinyl chloride) component is negligible.

Full paper in Portable Document Format: 271a84.pdf

Chemical Papers 27 (1) 84–89 (1973)