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PVC Matrix (pvc + matrix)
Selected AbstractsThe structure and dynamic properties of nitrile,butadiene rubber/poly(vinyl chloride)/hindered phenol crosslinked compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2008Ping Xiang Abstract In this article, a new nitrile,butadiene rubber (NBR) crosslinked composites containing poly(viny chloride) (PVC) and hindered phenol (AO-80 and AO-60) was successfully prepared by melt-blending procedure. Microstruture and dynamic mechanical properties of the composites were investigated using SEM, DSC, XRD, and DMTA. Most of hindered phenol was dissolved in the NBR/PVC matrix and formed a much fine dispersion. The results of DSC and DMTA showed that strong intermolecular interaction was formed between the hindered phenol and NBR/PVC matrix. The NBR/PVC/AO-80 crosslinked composites showed only one transition with higher glass transition temperature and higher tan , value than the neat matrix, whereas for the NBR/PVC/AO-60 crosslinked composites, a new transition appeared above the glass transition temperature of matrix, which was associated with the intermolecular interaction between AO-60 and PVC component of the matrix. Both AO-80 and AO-60 in the crosslinked composites existed in amorphous form. Furthermore, the chemical crosslinking of composites resulted in better properties of the materials, e.g., considerable tensile strength and applied elastic reversion. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Effect of acrylic core,shell rubber particles on the particulate flow and toughening of PVCJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2009M. R. Moghbeli Abstract Different types of acrylic core,shell rubber particles with a poly(butyl acrylate) (PBA) core and a grafted poly(methyl methacrylate) (PMMA) shell were synthesized. The average size of acrylic core,shell latex particles ranged from 100 to 170 nm in diameter, having the core gel content in the range of 35,80%. The melt blending behavior of the poly(vinyl chloride) (PVC) and the acrylic core,shell rubber materials having different average particle sizes and gel contents was investigated in a batch mixing process. Although the torque curves showed that the particulate flow of the PVC in the blends was dominant, some differences were observed when the size and gel content of the particles varied. This behavior can be attributed to differences in the plasticizing effect and dispersion state of various types of core,shell rubber particles, which can vary the gelatin process of the PVC in the mixing tool. On the other hand, the highest toughening efficiency was obtained using core,shell rubber particles with the smallest particle size (i.e., 100 nm). The results showed that increasing the gel content of the core,shell impact modifiers with the same particle size improved the particle dispersion state in the PVC matrix. The toughening efficiency decreased for the blends containing 100 and 170 nm rubber particles as the gel content increased. Nevertheless, unexpected behavior was observed for the blends containing 140 nm rubber particles. It was found that a high level of toughness could be achieved if the acrylic core,shell rubber particles as small as 100 nm had a lower gel content. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Kinetics of interaction of palm ethyl biodiesel with three different polymer materialsJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 12 2008Giselle Lutz Abstract Diesel diffuses into neoprene matrices 10% faster than palm ethyl biodiesel at 20°C. In contrast, the palm biodiesel soaks highly plasticized PVC five times faster than diesel. Phthalate plasticizer leaks from the PVC matrix 14 times faster when biodiesel is the absorbed liquid, relative to petrodiesel. This biodiesel penetrates polybutadiene-styrene resins at rates that depend on the ratio of phenyl to CHCH units in the resins. Copyright © 2008 John Wiley & Sons, Ltd. [source] Fusion characteristics of rigid PVC/wood-flour composites by torque rheometryJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 1 2007Laurent M. Matuana This study was aimed at examining the effects of wood flour contents, wood species (softwood vs. hardwood), and particle size on the fusion characteristics (fusion time, fusion temperature, fusion torque, and fusion energy) of rigid PVC/wood-flour composites in a torque rheometer. Neat rigid PVC exhibited one fusion peak, whereas the addition of wood flour into the PVC matrix led to two fusion peaks. Increased wood flour content caused a significant increase in the time, temperature, and energy at which fusion between the primary particles started, thereby leading to increased fusion torque, irrespective of the wood flour species. These results implied that rigid PVC filled with wood flour must be processed at higher temperatures than neat resin. Although fusion characteristics of the composites were influenced by the wood species, a clear trend between softwood and hardwood species could not be established. However, finer particles fused more quickly and needed less energy than coarse ones. J. VINYL ADDIT. TECHNOL., 13:7,13, 2007. © 2007 Society of Plastics Engineers. [source] Quasi-brittle to ductile transition in impact-modified PVCJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 1 2004J. Yu The toughness of impact-modified poly(vinyl chloride) (PVC) compounds was examined by using a modified Charpy test. Increasing impact speed resulted in a quasi-brittle to ductile transition in all PVC compounds. In the quasi-brittle region, a PVC of 56,000 Mw fractured through a craze-like damage zone that could be described by a modified Dugdale model. Furthermore, the same molecular-weight PVC modified with either 10 pph (parts per hundred parts by weight) of chlorinated polyethylene (CPE) or 10 pph of methylmethacrylate-butadiene-styrene (MBS) impact modifier also conformed to the Dugdale model with the craze-like damage zone. The CPE effectively improved the impact performance of PVC by shifting the quasi-brittle to ductile transition to a higher loading rate. Compared to CPE, MBS was a better impact modifier, and its use resulted in a higher quasi-brittle to ductile transition loading rate in the same PVC matrix. Fracture initiation toughness of all the materials was described by the Hayes-Williams modification of the Dugdale model. The intrinsic brittle fracture energy obtained by extrapolation to zero craze length was determined only by the PVC matrix and was independent of the impact modifier. However, the kinetics of craze growth, and hence the response to rapid loading, depended on the impact modifier. Increasing the molecular weight of the PVC resin resulted in a more complex damage zone that was not amendable to the Dugdale analysis. J. Vinyl Addit. Technol. 10:11,16, 2004. © 2004 Society of Plastics Engineers. [source] Preparation and Properties of PVC Ternary Nanocomposites Containing Elastomeric Nanoscale Particles and Exfoliated Sodium-MontmorilloniteMACROMOLECULAR MATERIALS & ENGINEERING, Issue 6 2006Qingguo Wang Abstract Summary: A novel rigid PVC ternary nanocomposite containing NBR-ENP and untreated Na-MMT has been fabricated. X-ray diffraction XRD, TEM and SEM observations revealed that the untreated Na-MMT was exfoliated and most NBR-ENPs (about 90 nm) were separately dispersed in the PVC matrix. DMTA and TGA demonstrated that the PVC ternary nanocomposites had a higher glass transition temperature and a higher decomposition temperature than neat PVC, while the toughness increased simultaneously. Combustion tests showed that the exfoliated clay in the PVC/NBR-ENP/MMT ternary nanocomposites did not improve the flame retardancy after ignition under strong heat flux. Schematic diagram of the fabrication procedure of PVC/NBR-ENP/Na-MMT ternary nanocomposites. [source] Effect of High-Energy Vibromilling on Interfacial Interaction and Mechanical Properties of PVC/Nano-CaCO3 CompositesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 9 2005Manhong Tian Abstract Summary: The effects of interfacial interaction between nano-CaCO3 and PVC on mechanical properties and morphology of PVC/nano-CaCO3 composites were studied. Nano-CaCO3 was treated with vibromilling in the presence of PVC and coupling agents. The mechanical properties of PVC/treated nano-CaCO3 are remarkably improved. Transmission electron microscopy results revealed that vibromilled nano-CaCO3 particles are well dispersed in PVC matrix with good homogeneity and well adhered to PVC matrix. Molau test indicated that chemical reaction between newly formed surface of nano-CaCO3 and PVC or coupling agent took place. Theoretical calculation results show that the interfacial interaction between PVC and nano-CaCO3 are substantially improved through vibromilling treatment of nano-CaCO3 in the presence of PVC and coupling agent. Molau test results of the samples in THF. [source] Development of novel conducting composites of nanostructured poly(1-naphthylamine) with poly(vinyl chloride)POLYMER COMPOSITES, Issue 5 2009Ufana Riaz Investigations on the synthesis of nanoconducting polymers have gained much popularity during the past few decades. The processibility of the nanostructured conducting polymers is poor, which hinders their commercial application. Considering the drawbacks of nanostructured conducting polymers, this article reports for the first time the synthesis of processible composites of nanostructured poly(1-naphthylamine) (PNA), a polyaniline derivative with poly(vinyl chloride) (PVC). The composites were prepared by loading different weight ratios of PNA (2,10 wt%) in PVC. The composites were characterized by spectral, thermal, morphological, and conductivity studies. The particle size of PNA/PVC composites was confirmed by transmission electron microscopy and was found to be in the range of 5,20 nm. The highest conductivity of 2.5 × 10,2 S/cm was obtained in the composite with 4 wt% loading of PNA. The high conductivity of the composites was correlated to the agglomerate-free uniform dispersion of self-assembled nanofibrillar network of PNA particles in the PVC matrix. The PNA/PVC composites exhibited good mechanical properties, which holds potential for use in semiconductor nanodevices. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers [source] Synthesis and characterization of poly(butyl acrylate- co -ethylhexyl acrylate)/ poly(vinyl chloride)[P(BA-EHA)/PVC] novel core-shell modifier and its impact modification for a poly(vinyl chloride)-based blendPOLYMER ENGINEERING & SCIENCE, Issue 6 2010Mingwang Pan Synthesis of poly(butyl acrylate-co-ethylhexyl acrylate)-core/poly(vinyl chloride)-shell [P(BA-EHA)/PVC] used as a modifying agent of PVC via semicontinuous seeded emulsion copolymerization is reported here. Diameter distributions and morphology of the composite latex particles were characterized with the aid of particle size analyzer and transmission electron microscopy (TEM). The grafting efficiency (GE) and grafting ratio (GR) of vinyl chloride (VC) grafted onto the P(BA-EHA) with varying content of crosslinking agent and core-shell ratios were investigated. TEM studies indicated that the P(BA-EHA)/PVC latex particles have core-shell structure, and the P(BA-EHA) rubbery particles in blending materials were uniformly dispersed in PVC matrix. Dynamic mechanical analysis (DMA) results revealed that the compatibility between the P(BA-EHA) and the PVC matrix was significantly improved due to the presence of the P(BA-EHA)-grafted-VC copolymer. The notched impact strength of the blending material with 3 wt% of rubber content was seven times that of the PVC. Linear regressions of mechanical properties as loading of the modifier were made. The resulting data of notched impact strength and elongation at break for the blending materials deviated significantly from regression lines within 3,4.5 wt% of the P(BA-EHA) content. The PVC blends modified by the modifier exhibited good toughness and easy processability. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers [source] The effects of water and frequency on fatigue crack growth rate in modified and unmodified polyvinyl chloridePOLYMER ENGINEERING & SCIENCE, Issue 2 2010Noorasikin Samat A study of the influence of water environments on the cyclic fatigue crack behavior of polyvinyl chloride (PVC), with (PVC-M) and without (PVC-U) chlorinated polyethylene (CPE) impact modifier was undertaken and compared with corresponding results in air. Two frequencies of 1 and 7 Hz were applied to assess the influence of frequency on the fatigue behavior; a higher fatigue resistance and threshold were obtained with increasing frequency. This trend is more significant in water. However, in this environment, the fatigue resistance deteriorated under conditions of higher stress intensity factor amplitude (,K) and frequency. The fatigue properties of PVC-U are the most affected by the presence of water, particularly at low frequency and higher ,K. Examination of the fracture surface showed the interaction of water molecules and the PVC matrix with the formation of (1) a nodular structure, close to the fatigue threshold and (2) plasticized structures at high ,K, which are associated with a greater threshold value and fatigue resistance. The absorption of the water retarded the fibrillation of craze and caused crack blunting effects. Water functions as a plasticizer, particularly at high ,K, through the formation of the plasticized structures. Results are compared with those observed from an in-service failure. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source] | ||||||||||