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The results of a study on latexes obtained by emulsion copolymerization of acrylic, methacrylic and vinyl monomers without surfactants are presented. The monomers included ethyl acrylate and butyl acrylate, methyl and butyl methacrylate and methacrylic acid. The yield of the copolymerization reaction, the polymer concentration in the latex, the pH, surface tension, intrinsic viscosity number, Huggins constant, the molecular weight of the polymer and the particle size in the latex were determined. The stability of the latexes was tested by determining the values of non‐overt and overt coagulation thresholds. The values of the limiting equivalent conductivity and the anode zeta potential were determined. The relative hardness of latex membranes and their mass change after hot water extraction were investigated. The relationships between the properties of individual latexes were established. The main aim of the research was to determine the influence of copolymer composition on the electrokinetic properties of polymer particles in latex. They determine the possibility of developing a new type of paint for electrophoretic painting with the use of latexes. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The modification of poly(vinyl chloride) (PVC) by polyhedral silsesquioxane containing both methacryl and octyl groups (MeOctPOSS) was the task of studies. The PVC nanocomposites with MeOctPOSS concentration between 1 and 10 wt% were prepared by melt mixing processing, and the homogeneity of MeOctPOSS dispersion in the polymeric matrix was confirmed by scanning electron microscopy and energy dispersive spectroscopy observations. The influence of MeOctPOSS on glass transition temperature (Tg) determined by means of dynamic mechanical thermal analysis (DMTA) and differential scanning calorimetry (DSC) was observed, whereas, higher the measurement frequency, higher the glass transition temperature was noted. The MeOctPOSS concentration‐dependent PVC glass transition temperature was shifted from 73.8°C to about 68°C (ƒ = 1 Hz) and from 76.5°C to 70.8°C (ƒ = 10 Hz) for increasing additive content. Similar result of decreasing Tg value was observed by DSC method. An introduction of 10 wt% of MeOctPOSS into the PVC matrix results in a visible decrease of the maximum value of loss modulus (G′) of approximately 12% and 18% by 1 Hz and 10 Hz, respectively, as well as in a significant reduction of the static elastic modulus. It was stated that the polyhedral oligomeric silsesquioxanes with both methacryl and octyl groups may act as plasticizers of the PVC matrix. J. VINYL ADDIT. TECHNOL., 25:E48–E54, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The preparation of nanocomposites by incorporation of nanoparticles, in particular the carbon nanotubes in a molten polymeric matrix could find potential application in industry technologies as a method of the manufacturing of new engineering materials. Considering the complex transformations of PVC grains during processing as well as weak dispersibility of nanotubes caused by their high tendency to agglomeration are crucial to investigate the influence of MWCNT content on PVC processability. For this purpose the plastographmetric analysis of processing of PVC/MWCNT blends are carried out. The results of the research show that the presence of nanotubes causes an increase in shearing stress, which leads to PVC grains disintegration and faster gelation compared to the unmodified PVC blend. At the same time, the carbon nanotubes dispersed in the molten PVC blend lead to intensification of the process, which occurs at a lower temperature. [ABSTRACT FROM AUTHOR]

The article discusses a study which analyzed the changes that occur in a poly(vinyl chloride) PVC compound that was processed in a Brabender plastograph. The study focused on the changes in the temperature of the compound in relation to kneading and its effect on the progress of PVC gelation. It found that processing of PVC in the kneader caused self-heating and resulted to increased temperature.