A method of rheokinetic analysis is applied to free‐radical polymerization of acrylamide in a water solution initiated by an oxidizing reducing system. The special feature of this system is the second‐order kinetics of the initiation stage. Theoretical analysis predicts the main effects, such as the time dependence of viscosity and the degree of polymerization, concentration influence of a monomer and an initiator, and the temperature dependence of the viscosity profile at different experimental conditions. Experimental data confirmed the idea about the second‐order reaction of initiation. Observed dependencies were close to theoretical predictions. Rate constants of different individual stages of a reaction and “apparent” values of activation energy were found and compared with published values. The possibility of solving an inverse rheokinetic problem from viscometric data was confirmed.
By means of in situ melt polycondensation of polyethylenterephathalate accompanied with simultaneous reduction of introduced graphene oxide, the composite of polyethylenterephathalate filled with reduced graphene oxide was prepared. Melting and crystallization of the reduced graphene oxide – polyethyleneterephthalate composite was studied by the differential scanning calorimetry method, and the rheological test was carried out by rotational rheometry and compared to the pristine polyethylenterephathalate. The morphology of the reduced graphene oxide – polyethyleneterephthalate composite was studied using optical microscopy. The reduced graphene oxide was isolated from the reduced graphene oxide – polyethyleneterephthalate composite and characterized by thermogravimetry, X-ray photoelectron spectroscopy and X-Ray diffraction methods. Since a part of polymer could not be removed from reduced graphene oxide particles by trifluoroacetic acid, the hypothesis about probable grafting of polyethyleneterephthalate on reduced graphene oxide sheets was suggested. Rheological behaviour of the reduced graphene oxide – polyethyleneterephthalate composite melt confirms this suggestion. According to the calculations based on thermogravimetry, the reduced graphene oxide, isolated from the reduced graphene oxide – polyethyleneterephthalate composite, consists of about 80% polyethyleneterephthalate.
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