Papers by Keyword: Poly(vinyl chloride)

Abstract: The structure of basic lanthanum orotate (LaOr) were characterized by elemental analysis and infrared spectroscopy. The thermal stability of polyvinyl chloride (PVC) was further studied by Congo red method, oven discoloration method and thermogravimetric analysis. The results showed that LaOr could prolong the oven discoloration time of PVC, and the color was not completely blackened until 120 min. It has a good synergetic effect with dibenzoyl methane (DBM), and the best effect is achieved when LaOr/DBM ratio is 1.8/1.2. The thermal decomposition kinetics experiment showed that adding DBM can effectively improve the activation energy of PVC/LaOr. The stabilization mechanism of PVC was studied by absorbing HCl method and infrared spectroscopy. The results showed that LaOr could not only replace the unstable chlorine atoms on PVC, but also promote the long-term thermal stability of PVC by absorbing HCl.

Abstract: Novel extracted natural stabilizer for the polymer was investigated in this study. The natural anti-aging was extracted from plants and it is demonstrated that this type of stabilizers are suitable for biodegradable polymers. Gynostemma pentaphyllum (0.01–0.03 wt%) were extracted and added to the poly(vinyl chloride) blend. The achieved polymeric films were exposed to an accelerated UV light aging process for 300 hours at ambient temperature. The efficiency of tested natural stabilizer was linked to blank PVC films. FTIR spectroscopy, weight loss, electronic microscope and scanning electron microscopy were performed. Using small amount of natural stabilizer is significantly beneficial because it does not influence the PVC properties.

Abstract: Polymer conductive films based on poly (ethylene oxide) (PEO), poly (vinyl chloride) (PVC), polyaniline (PANI) were prepared using solution casting method. The effect of polyaniline loading on the tensile properties, swelling behavior, and electrical conductivity of PVC/PEO conductive films were studied. The tensile strength of PVC/PEO conductive films decrease with increasing of PANI loading. The mass swell percentages and electrical conductivity increased with the increasing polyaniline loading of PVC/PEO conductive films.

Abstract: The effect of orotic acid (OA) and its mixtures with calcium stearate (CaSt₂) and zinc stearate (ZnSt₂) in various ratios on the thermal stability of PVC has been investigated by Congo red and discoloration tests. The results shows that OA acts as a long-term thermal stabilizer for PVC like CaSt₂, and the combination of OA and ZnSt₂ exhibited a synergistic stabilization effect at a certain ratio. This is due to the ability of OA to absorb HCl released during the degradation of PVC to diminish its catalytic effects, and react with ZnCl₂ to stop its catalytic effect for PVC. CaSt₂-ZnSt₂/OA stabilizers exhibit good synergistic effects with both acceptable initial color and long-term stability for PVC

Abstract: Conductive polymer films based on carbon black filled PVC/PEO (50/50 wt/wt %) was prepared by solution casting technique. The effect of carbon black loading on the electrical conductivity and thermal degradation was studied. The result shows that the electrical conductivity increased with increasing of carbon black loading. The thermal degradation of the PVC/PEO conductive blends were performed using Thermogravimetric analysis (TGA). The TGA data indicates that the addition of carbon black into the blend was improved the thermal stability of the PVC/PEO blends.

Abstract: This paper presents measurement of tensile proprieties of thermoplastics by digital image correlation method. The objectives are to characterize based on experimental data the pre-and post-yield regime of polyvinylchloride (PVC) under uniaxial tension and to investigate the rate-dependent large deformation behaviour over crosshead speeds of 1, 5 and 25 mm/min respectively. The true strain-stress curves of PVC tested with different loading speeds are experimentally obtained and based on these a phenomenological constitutive model is implemented. The theoretical material model considers the variation of strain rates due to the inhomogeneous deformation behaviour of thermoplastic polymer and includes six parameters (material constants) to be identified according to the experimental results. It can be found that the effect of the strain rate on the true stress strain curves is small for lower strain rates but cannot be ignored for higher strain rate.

Abstract: The purpose of this research is to enhance the toughness of richly-filled wood plastic composites (WPC) by using ultrafine acrylonitrile butadiene rubber (NBR) particles. The WPC was prepared by using poly (vinyl chloride) (PVC) matrix filled with Iron wood (Xylia xylocarpa) flour at 40 phr (WPC40) and 60 phr (WPC60). To enhance the impact strength, various contents of the ultrafine NBR were incorporated as an impact modifier from 1-11 phr. Experimental results indicated that the NBR toughened-WPCs were tougher than that of the unmodified ones, by increasing the tensile elongation at break. The impact strength of the WPCs modified with only 5 phr of NBR was notably enhanced around 26 and 7% for WPC40 and WPC60 respectively. Rheological results revealed that the ultrafine NBR functioned not only as an impact modifier but also as a processing aid with shorter processing time and lower melt torque.

Abstract: Poly (vinyl chloride) (PVC) hollow fiber membranes were prepared via non-solvent induced phase separation (NIPS), the effect of bore liquid flow rate (BLFR) on the structure and properties of the membrane were investigated. The results show that the prepared PVC hollow fiber membrane has a finger-sponge-finger-like structure, the thickness of the sponge-like intermediate layer decreases with the increase of BLFR. Both the inside diameter and outside diameter increase, while the wall thickness of the PVC hollow fiber membrane decreases with the increase of BLFR. The tensile strength and elongation decrease, the permeate flux increases, while the rejection of the particles decreases little with the increase of BLFR.

Abstract: Mechanical properties, abrasion properties, thermal stabilities, and dynamic mechanical properties of poly (vinyl chloride) (PVC)/diatomite composites with different diatomite content prepared by melting blending were investigated. The results indicated that mechanical properties of composites have different performance due to diatomite participation, and the flexural modulus was improved. With an increase in diatomite, the abrasion resistance and thermal stability of composites were improved. Furthermore, the E' and T_g of composites could be enhanced effectively with diatomite participation. The optimum combined properties of PVC/diatomite composite were obtained with the adding of 40 phr diatomite.

Abstract: Two commercial fungicides, namely, 3-Iodopropinyl-N-butylcarbamate (IPBC) and Methylbenzimidazole-2-ylcarbamate (Carbendazim) were used to improve anti-fungal properties of poly (vinyl chloride) (PVC) and wood/PVC composite (WPVC) materials. Disk diffusion test and dry weight technique, using Aspergillus niger as a testing fungi, were employed for the anti-fungal assessments. The effects of type and content of fungicides on anti-fungal performances were discussed in association with material properties. For material property characterizations, flexural properties, surface contact angle and surface color changes were observed. The results from anti-fungal test by disk diffusion test revealed that addition of IPBC in PVC or WPVC showed much greater anti-fungal performance than that of Carbendazim in PVC or WPVC. The WPVC samples exhibited better anti-fungal performances than the PVC samples. It can be concluded that wood particles could promote the fungicidal effect of the WPVC composites. It was found that type and content of fungicides used did not significantly alter the flexural properties of the materials whereas the presence of wood resulted in an increase of flexural modulus with a decrease in flexural strength. The surface contact and color changes of PVC and WPVC were observed with addition of IPBC, but not found with Carbendazim.