PVC in the form of emulsion resin is used in plastisol technology. Among its disadvantages: resin degradation during melt processing, high melt and gel temperature, resin's high viscosity in gel and melt temperature and low solubility can be mentioned. Copolymerization of vinyl chloride wih other monomers is a suitable route to modify such properties. Vinyl acetate comonomer improves many of the PVC problems. In this study copolymerization of vinyl chloride with 15.2 percent vinyl acetate was performed in a batch emulsion copolymerization system. Vinyl chloride content in both gas and liquid phase in the reactor, pressure variation and the effect of initiation on the reaction kinetics were investigated. Chemical structure and copolymer composition were characterized by FTIR and NMR spectroscopy. K-Value of the copolymers which is related to molecular weight was determined by solution viscometry.

The thermal decomposition of 86 % vinyl chloride 14 % vinyl acetate copolymer was studied by the conductometry technique in the presence of nitrogen. The kinetics of stability and thermal degradation of vinyl chloride- co- vinyl acetate (PVC- co- PVAc) copolymer with copper, copper oxide and tricalcium dicitrate (st) were investigated at various temperatures (150-180oC) in solution. The rate coefficients for the degradation of the copolymer were determined. The energies of activation, determined from the temperature dependence of the rate coefficients for copolymer alone was 63.536 kJ mol-1 and in the presence of copper, copper oxide and tricalcium dicitrate were 44.224, 55.594 and 110.332 KJ mol-1, respectively. The results show that thermal stability was increased in the presence of tricalcium dicitrate, but its thermal stability was decreased in the presence of copper and copper oxide.

Emulsion copolymerization of vinyl chloride with vinyl acetate comonomer was performed.Different conditions of initiators, emulsifier, and comonomer concentration were chosen in order to investigate the copolymerization reaction. Potassium persulphate,a mixture of stearyl alcohol and sodium lauryl sulphate (SLS) were used and reactions were performed at 55°C in a pressurized reactor. Two region of pressure change were distinguished in the pressure-time curves in which by increasing the initiator concentration the flat region was shortened and the descending region showed a higher slope indicating higher reaction rate. Higher initial pressure was found in higher emulsifier concentration while higher pressure drop was achieved in the second region of pressure-time curves. Effect of comonomer content on heat release during copolymerization was studied. Conversion and intrinsic viscosity of the copolymers and their correlation with reaction parameters were also investigated.

A mixture of sodium lauryl sulfate (SLS) as ionic emulsifier and stearyl alcohol as non-ionic emulsifier was employed in a vinyl chloride emulsion polymerization reaction to study the influence of various interactive parameters involved in the reaction system. It was found that the particle size was dependent on the amount and type of emulsifier. The average particle size of polyvinyl chloride was dropped by higher amount of emulsifying agents. At the gel point, more heat was generated by higher amount of vinyl chloride fed into the reaction system. The molecular weight of the polymer was decreased by increases in reaction temperature while, it increased by augmenting the amount of emulsifier. According to the 13C NMR and FTIR spectroscopic data no defect was detected in the chain structure of synthetic polyvinylchloride product. An optimization of polymerization reaction condition was reached based on ultimate particle size desired for its favorable distribution in plastisols.

In this work, the photo-stabilization of poly (vinyl chloride) was studied using new compounds such as Schiff base stabilizers derived from heterocyclic compounds, with symbols [I1-I4] which were used as additives to prevent the PVC photodegradation. Many samples have been prepared as films for this purpose by adding the additives to poly (vinyl chloride) with varying weight percentages of additives and thicknesses. The photostabilization activities for these new compounds were measured by detecting the carbonyl group with irradiation time (the absorption band of carbonyl was determined at 1724-1772 cm-1). FT-IR spectra PERKIN ELMER SPEACTUM-65, JASCO used to determine the absorption spectra of PVC films, also the viscosity average molecular weight , the average number of chain scission (S), and the degree of deterioration (α) were studied. Scanning Electron Microscope (SEM) and light microscope are also used to test the polymeric films surface. We discovered that in the existence of additives, the rate of photostabilization follows the trend:-

In this paper an experimental study is presented to investigate the effectiveness of UPVC tube for confinement of concrete columns. UPVC tubes having 140 mm, 160 mm and 200 mm external diameters were used to confine the concrete having compressive strength 20 MPa, 25 MPa and 40 MPa. The concrete has been designed using IS code 10262-1982 (Reaffirmed −2004) (BIS: 10262–1982, Reaffirmed −2004). The testing of the specimens was carried out on a displacement controlled Instron make Universal Testing Machine of 2500 kN capacity. During the experiments mode of deformation and corresponding load-compression curves were recorded and obtained results are compared with the existing models for confined concrete available in the literature. It is found that the predicted capacities of columns using different models are within ±6% of the experimental capacities. It is found that UPVC tubes can be effectively used for confinement of the concrete columns and to enhance their load capacity, ductility as well as energy absorbing capacity.