Abstract

Metal poly(styrene-co-4-methylstyrene)s copolymers were obtained by radical copolymerization with azobiisobutyronitrile. The monomers were cocondensed simultaneously with the metals: Pd, Cu, Ag, Au, Zn, Ga, In, Ge, Sn, Sb and Bi. The metals were evaporated to produce atoms and with the monomers they can produce a matrix at 77 K. After the warm up process, metal comonomer colloids can be obtained. The colloids were polymerized with azobiisobutyronitrile at 65°C for 3 h. Four different initiator concentrations (0.1, 0.5, 1.0 and 2.5 mol%) were used. The yields are over 30% and the viscosimetric molecular weight ranges from 103-105 g/mol. The higher Mv are Bi, In and Pd-poly(styrene-co-4-methylstyrene) copolymers. The thermal stabilities of these metal polymers have been studied by thermogravimetry (TG) between 25 and 550°C under nitrogen flow. The decomposition temperature was obtained from the maximum of the first derivative from TG curve. The kinetic parameters of the thermal decomposition were determined by the Arrhenius equation. All these copolymers degrade in one stage. The kinetic data thus obtained show the thermostabilities decrease in the order: Zn-(S-4MeS) > Bi-(S-4MeS) > In-(S-4MeS) > Sb(S-4MeS) > Ga(S-4MeS) > Pd-(S-4MeS) > Ag(S-4MeS) > Au-(S-4MeS) > Sn-(S-4MeS) > Ge-(S-4MeS). The thermal stability apparently is dependent upon the metal incorporated in the copolymers. The decomposition reaction order is zero. The pre-exponential factor, the activation energy, the reaction order and the decomposition temperature for all the copolymers have been determined.