Free radical copolymerization of methacrylic acid (MA) with styrene (St) at 60"C, initiated by 2,2'-azoisobutyronitrile (AIBN) is carried out in hydrogen-bond forming solvents and in solvents not capable of forming hydrogen bonds but exhibiting different dielectric constants. The influence of the solvent on copolymerization reactivity ratios, rate of polymerization, composition, molecular weight and polydispersity of the copolymers obtained is shown. The reactivity ratios of methacrylic acid TMA and of styrene rst are determined by two different methods with good agreement. The values obtained by the Kelen-Tiidbs method are as follows: in carbon tetrachloride: rMA = 0,54 f 0,Ol; rst = 0,06 f 0,03; in chloroform: rm = 0,51 f 0,Ol; rst = 0,08 f 0,03; in acetone: rMA = 0,43 f 0,OO; rst = 0,65 f 0,02; in 1,Cdioxane: rMA = 0,41 f 0,02; rst = 0,59 f 0,05; in acetonitrile: rm. 7 0,06 k 0,02; rst = 0,29 f 0,OO.from IR and H NMR spectroscopy and gel permeation chromatography (GPC).Changes of reactivity ratios depending on the medium are explained on the basis of the results 0025-1 16)3/85/$03.00

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S U M M A R Y :The polymerization of furfuryl methacrylate (FMA) and carbomethoxyfurfuryl methacrylate (CMFMA) has been studied. It has been established that under equal conditions the rate of CMFMA polymerization is greater than the rate of polymerization of FMA. The temperature dependence of the rate constants showed that the polymerization of FMA is associated with a greater energy of activation. These results are explained by z-complex formation between the furan nuclei on the one hand and the methacrylic double bonds or the growing methacrylic radicals on the other. Complex stability depends on the electron-donor capacity of the furan nuclei. ZUSAMMENFASSUNG:Die Polymerisation von Furfurylmethacrylat (FMA) und Carbomethoxyfurfurylmethacrylat (CMFMA) wurde untersucht. Unter gleichen Bedingungen ist die Polymerisationsgeschwindigkeit von CMFMA grol3er als diejenige von FMA. Die Temperaturabhangigkeit der Geschwindigkeitskonstanten zeigte aunerdem, da13 die FMA-Polymerisation mit einer grol3eren Aktivierungsenergie verbunden ist.Diese Ergebnisse wurden mit einer x-Komplexbildung zwischen den Furanringen einerseits und den Methacrylatdoppelbindungen oder den wachsenden Methacrylatradikalen anderseits erklart. Die Stabilitat der Komplexe hangt von der Elektronenabgabekapazitat der Furanringe ab.

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Polymerizations of I-naphthyl methacrylate and 2-naphthyl methacrylate in acetone and in acetonitrile were carried out in the presence of 2,2'-azoisobutyronitrile at 55 and 60 "C, respectively. The polymers precipitate during the polymerization. Poly(1-naphthyl methacry1ate)s are partly soluble in common organic solvents. The polymerization medium does not influence noticeably the intrinsic viscosity of the resulting polymers. The tacticity was determined by 'H NMR analysis after conversion of the poly(naphthy1 methacry1ate)s into poly(methy1 methacry1ate)s. Poly(naphthy1 methacry1ate)s obtained in acetone and acetonitrile have a higher content ofisotactic triads than those obtained in solvents with low dielectric constants. The observed results correlate with the changes in the 'H NMR spectra ofthe monomers depending on the dielectric constants of the solvents.Part 2: cf.6'.