4-metil-2-okso-2H-kromen-7-il metakrilat ve metil metakrilat kopolimerlerinin termal ve elektriksel özellikleri üzerine grafit oksitin etkisi

The random copolymers of 4-methyl-2-oxo-2H-chromen-7-yl methacrylate (COUMA) and methyl methacrylate (MMA) P(COUMA8.9%, 24%, 36%, 49%, 65%-co-MMA) were prepared via the conventional free radical polymerization method. The copolymers were characterized by 1H-NMR, FT-IR, UV-vis, TGA and DSC instruments. A kinetic study of the thermal decomposition of P(COUMA49%-co-MMA) COMCOP1 and P(COUMA49%-co-MMA)/ GO 16 wt.% COMCOP1/GO 16wt.% was investigated using thermogravimetric analysis with non-isothermal methods selected for analyzing solid-state kinetics data. The average activation energy values were calculated via FWO and KAS models in a period of α = 0.10 - 0.70. The average values of activation energy obtained from Kissinger method for COMCOP1 and COMCOP1/GO 16 wt.% were 94.5 kJ mol-1 and 101 kJ/mol, respectively. Whereas, those of estimated by FWO method were 103.5 and 87.0 kJ/mol. This study indicated that well-defined single chain polymer molecule (SCPM) via intramolecular cyclobutane formation could be obtained by the intrachain photodimerization of coumarin groups under UV irradiation at 365 nm diluted solution of COMCOP1. The photodimerization of coumarin groups in the copolymer was confirmed by UV-vis, FT-IR and 1H-NMR instruments. Electrical and dielectric behaviors of the composites having a semi-conductor behavior filled with GO at various filler loadings were investigated. The activation energy values based on DC conductivity for COMCOP1 loaded GO 10 wt.% and 12 wt.% were decreased from 0.206 to 0.069 eV. Also, the Ea values estimated for COMCOP2 loaded GO 12 wt.% and 13.6 wt.% were 0.0580 eV and 0.0859 eV , respectively.