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a b s t r a c tIn this study, Co, Cr or Au 3+ functional polystyrene-block-poly(2-vinylpyridine), PS-b-P2VP complexes were prepared and characterized. Coordination of metal atom or ion to nitrogen atom of pyridine rings was confirmed by FTIR analyses. The strength and efficiency of coordination of P2VP blocks to Co, Cr or Au 3+ mainly depends on charge and stability of the complex formed that is mainly related to the energy of d orbitals. The results reveal that the thermal stability of the polymer composite formed increases with the increase in strength of the coordination. Changes in thermal decomposition mechanism and product distribution were recorded. Degradation of P2VP units coordinated to Cr, Co or Au 3+ was started by loss of pyridine units leaving an unsaturated and/or crosslinked polymer backbone that degraded at relatively high temperatures.

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In this study, polystyrene-block-poly(2-vinylpyridine), PS-b-P2VP, polyisoprene-block-poly(2-vinylpyridne), PI-b-P2VP and poly(methyl metacrylate)-block-poly(2-vinylpyridine), PMMA-b-P2VP, coordinated to Cr metal were synthesized and characterized by Fourier transform infrared, transmission electron microscopy and direct pyrolysis mass spectrometry techniques. Both thermal degradation mechanism and thermal stability of P2VP blocks were affected by the coordination of Cr nanoparticles to nitrogen of pyridine rings. Thermal decomposition of P2VP blocks was started by loss of pyridine units leaving an unsaturated and/or crosslinked polymer backbone that degraded at relatively high temperatures. Incorporation of Cr metal did not noticeably influence thermal behavior of PS and PI blocks. However, increase in thermal stability of PMMA block was detected and associated with inhibition of the interactions between carbonyl groups of MMA chains with nitrogen atom of pyridine ring as a consequence of coordination to metal.