Thermal Behaviour Prediction of Rigid Polyvinyl Chloride (original) (raw)
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Polymers, 2021
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Statistical thermal stability of PVC
Journal of Applied Polymer Science, 2010
Experimental design was used to optimize the processing parameters for the decomposition of poly (vinyl chloride). Factorial design and face centered composite design (FCC) were applied to determine the optimum conditions. A total of 10 g PVC powder was mixed with different amounts of zinc stearate (ZnSt 2 ) and natural zeolite and tested for thermal stability. Factorial fitted model was explained by first order pattern due to the significant main effect regression constants, and FCC model was described by second order model owing to higher order polynomial coefficients. FCC design was superior to factorial design as FCC considers not only its pure quad-ratic effects contribution but also its higher overall desirability for thermal stability of PVC. For factorial design the optimum conditions were determined as 163.06 mg for ZnSt 2 , 399.99 mg for zeolite, and 140 C for temperature with desirability of 0.933. However, 400 mg for ZnSt 2 , 333.24 mg for zeolite, and 140 C for temperature with desirability of 0.956 were obtained as the optimum conditions by FCC design.
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Due to a widely increasing usage of polymers in various industrial applications, there should be a continuous need in doing research investigations for better understanding of their properties. These applications require the usage of the polymer in different working environments subjecting the material to various temperature ranges. In this paper, an experimental investigation of mechanical properties of polyvinyl chloride (PVC) polymer under heating and cooling conditions is presented. For this purpose standard samples are prepared and tested in laboratory using universal material testing apparatus. The samples are tested under different conditions including the room temperature environment, cooling in a refrigerator, and heating at different heating temperatures. It is observed that the strength of the tested samples decreases with the increasing of heating temperature and accordingly the material becomes softer. Meanwhile the cooling environments give a clear increasing to the st...
Annales de Chimie - Science des Matériaux
Thermal aging below the glass transition temperature (Tg), during three months, of Poly (vinyl chloride) (PVC) under its three different aspects, powder (p-PVC), dry-blend and Unplasticized (u-PVC) or rigid form was performed. The stabilizing system used is a commercial compound constituted by lead based stabilizers, internal and external lubricants. The ageing of PVC under these three different aspects was performed in a thermo-regulated oven at 60 °C, temperature close of the ground temperature in Sub-Sahara region (Ghardaï a, Algeria). A sampling at regular interval allowed following the microstructural changes undergone by these materials. Such an approach revealed that the additives used in the PVC recipe not only assist processing but also ensured a good material stabilization when thermal aged. The results obtain can help producers to modify the PVC recipe to improve the heat resistance of the PVC tubes to make them more performing in the very hot and deleterious Saharan environment.
Polyolefins Journal, 2023
Thermo-mechanical recycling process is the cheapest way to recover plastic waste such as LDPE with low ecological impact. Thus, the goal of this work is to obtain high-performance microcomposites from polyvinyl chloride (PVC), recycled low-density polyethylene (r-LDPE), calcium carbonate (CaCO 3), and calcium/zinc stearate (CaSt 2 /ZnSt 2). The effect of the two ratios of thermal stabilizers with different concentrations on the mechanical properties and thermal stability of PVC and PVC/r-LDPE (1:1) blend was studied. The samples were characterized using infrared spectroscopy (FTIR), mechanical tests, thermal analysis, and scanning electron microscopy (SEM). The addition of 5 phr of CaSt 2 :ZnSt 2 (9:1) to PVC (MC4) resulted in optimal tensile strength and elongationat-break values. In addition, MC4 showed high thermal stability. Moreover, the incorporation of r-LDPE into PVC made the PVC matrix stronger and more stable than pure PVC, which yields high mechanical and thermal performances. Furthermore, an outstanding synergistic effect is obtained when a heat stabilizer rich in calcium is combined with CaCO 3 and r-LDPE. This PVC/r-LDPE blend as a composite can be used in several industrial fields.
Structural aspects of suspension poly(vinyl chloride): The thermal aspects of rigid suspension PVC
Journal of Polymer Science Part B: Polymer Physics, 1994
The structural aspects of rigid suspension poly (vinyl chloride), PVC, have been investigated on the basis of two independent series of suspension PVC samples, polymerized at temperatures between 26 and 84°C. The reproducibility of the suspension polymerization process and the importance of the polymerization temperature with respect to the macro-and microstructure is demonstrated. Quantitative examination of the grain structure by small angle neutron scattering, Brunauer-Emmett-Teller absorption technique, and mercury porosimetry clarifies the gradual increase of the specific surface on lowering the polymerization temperature. A detailed WAXS study shows an increasing degree of crystallinity on lowering the polymerization temperature, which can be associated with the corresponding increase of the syndiotacticity. Furthermore, the presence of a polymerization history in the PVC powders with respect to the crystallinity is evidenced. This effect seems to be related to chain mobility restrictions during the polymerization process and is determined by the difference between the polymerization temperature and the glass-transition temperature ( T,) of rigid PVC. This so-called Tg effect is indicative of the fact that no appreciable swelling of PVC by its monomer occurs. 0 1994 John Wiley & Sons, Inc. Keywords: poly(viny1 chloride) polymerisation conversion tacticity molar mass polymerization temperature microstructure macrostructure wide angle x-ray scattering small-angle neutron scattering Brunauer-Emmett-Teller absorption technique
FOR WASTE POLYVINYL CHLORIDE (PVC) PRODUCTS
The utilization of products based on the poly(vinyl chloride) (PVC) is constantly growing globally. In parallel to this a considerable quantity of PVC waste is also generated from various industrial and commercial products. The lower thermal stability of the PVC molecular structure and various additives incorporated during the manufacturing are limiting the recycling possibilities of PVC. Similarly, burning and land filling of endof-life PVC products also adversely affects biota and human beings due