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PREPARATION AND CHARACTERIZATION OF COMPOSITES COMPRISING MODIFIED HARDWOOD AND WOOD POLYMERS/POLY(VINYL CHLORIDE)  [PDF]
Ruxanda Bod?rl?u,Carmen Alice Teac?,Iuliana Spiridon
BioResources , 2000,
Abstract: Chemical modification of hardwood sawdust from ash-tree species was carried out with a solution of maleic anhydride in acetone. Wood polymers, lignin, and cellulose were isolated from the wood sawdust and modified by the same method. Samples were characterized by Fourier transform infrared spectroscopy (FTIR), providing evidence that maleic anhydride esterifies the free hydroxyl groups of the wood polymer components. Composites comprising chemically modified wood sawdust and wood polymers (cellulose, lignin)-as variable weight percentages-, and poly (vinyl chloride) were obtained and further characterized by using FTIR spectroscopy and scanning electron microscopy (SEM). The thermal behavior of composites was investigated by using the thermogravimetric analysis (TGA). In all cases, thermal properties were affected by fillers addition.
Synthesis and Photostability Study of Some Modified Poly(vinyl chloride) Containing Pendant Benzothiazole and Benzimidozole Ring
Emad Yousif,Ayad Hameed,Rashed Rasheed,Hadeel Mansoor
International Journal of Chemistry , 2010, DOI: 10.5539/ijc.v2n1p65
Abstract: The influence of introducing benzothiazole and benzimidazole as a pending groups into the repeating unit of PVC has been studied on the bases of photostability measurements. The photostability of modified polymers were studied by monitoring the carbonyl Index (ICO), polyene index (Ipo) and hydroxyl index (IOH), all results obtained indicated that PAA, PSS, PNN, PSA and PNA gave lower growth rate of ICO, IPO and IOH with irradiation time with respect to unmodified PVC film (control). The following trends of photostability are obtained PAA>PSS>PNN>PSA>PNA According to the experimental results several reaction mechanisms were proposed depending on the presence of benzothiazole and benzimidazole moieties in the polymer chain. The mode of chain scission was also investigated by measuring the variation of average viscosity molecular weight with irradiation time for modified PVC. The degree of deterioration (?) and the average number of chain scission (S) values were also calculated.
Investigation of poly (Vinyl Chloride-Co-Isobutyl Vinyl Ether) modified by Nano-TiO2 with XPS
添加纳米TiO2的氯醚树脂的XPS分析

XIANG Bin,LI Yan,ZHANG Sheng-tao,HOU Bao-rong,
向 斌
,李 焰,张胜涛,侯保荣

海洋科学 , 2006,
Abstract: Poly (Vinyl Chloride-Co-Isobutyl Vinyl Ether) (PVCCIVE) with rutile and anatase nano-TiO2 was investigated with XPS before and after UV light exposure respectively. The results indicate that the elements such as Chlorine and Oxygen in the PVCCIVE resin are rich in the surface, namely skin effect, in contrast, Titanium and Carbon are rich in the inner. Meanwhile, the smaller the pigment particles, the higher the content in the surface. The results also show that the rutile nano-TiO2 is excellent in UV screening and reduces the ageing of resin, while the anatase nano-TiO2 is highly active in photo catalysis and accelerates the ageing of resin. Hence then, rutile nano-TiO2 is a kind of promising UV absorber.
Study of the behavior of poly(vinyl chloride) and functionalized polyethylene blends
González,Jeanette; Rosales,Carmen; Hernández,Marianella; Ichazo,Miren;
Revista Técnica de la Facultad de Ingeniería Universidad del Zulia , 2007,
Abstract: in this research, blends of commercial poly(vinyl chloride) with linear low density polyethylenes (lldpe) and high density polyethylenes (hdpe) pure and functionalized were evaluated. different proportions of initiator (dicumyl peroxide-dcp) and 10 phr of a functionalizing agent (diethyl maleate-dem) were used in order to accomplish the functionalization of polyethylenes. the compounds were prepared in a twin screw extruder with a pvc/pe blend ratio of 65/35. the functionalization degree was determined by infrared spectroscopy (ftir). blends were characterized by differential scanning calorimetry (dsc) and by mechanical testing (tensile and impact strength); the morphology of the blends was also determined by scanning electron microscopy (sem). results obtained indicate that the functionalization of polyethylenes improves the processability of their blends with pvc. for the blends of pvc with lower k value and grafted lldpe with lower molecular weigth, not variation on the impact strength was obtained; samples more translucent were observed, as well as a reduction in the size of the structures in the disperse phase seen on the micrographs. this result seems to be closely related to the viscosity ratio of the components of these blends. concerning tensile properties a reduction in young?s modulus, tensile strength and elongation at break was found for all blends studied.
The Effect of Interfacial Interactions on a Structure and Properties of Polyurethane Elastomer/Poly(Vinyl Chloride) Blends  [PDF]
T. L. Malysheva, S. V. Golovan, D. L. Starokadomsky
Open Journal of Organic Polymer Materials (OJOPM) , 2011, DOI: 10.4236/ojopm.2011.11001
Abstract: The effect of chemical structure of segmented poly(urethane-urea)s on its interfacial interactions with poly(vinyl chloride) as well as supramolecular structure and the properties of prepared composites has been studied. A direct influence of flexible and rigid segments of elastomers on a compatibility, structure and the physical-mechanical properties of poly(urethane-urea)/poly(vinyl chloride) blends was investigated. A formation of intermolecular hydrogen bonds network in the poly(urethane-urea)/poly(vinyl chloride) systems was evaluated by FTIR analysis. Morphology studies have shown the effect of interfacial interactions on a size of thermoplastic phase dispersed within elastomer matrix. Obtained poly(urethane-urea)/poly(vinyl chloride) micro- and nanocomposites have improved tensile properties.
Thermal, dielectric and mechanical study of poly(vinyl chloride)/olive pomace composites
eXPRESS Polymer Letters , 2007, DOI: 10.3144/expresspolymlett.2007.117
Abstract: Composites from PVC and chemically treated olive pomace have been prepared. The effect of the incorporation of virgin and benzylated olive pomace in the poly(vinyl chloride) matrix on dielectric, mechanical and thermal stability properties, of /olive pomace composites was studied. The mechanical properties of the benzylated composites were improved. Furthermore, the thermal characterization of the different samples carried out by thermogravimetric analysis revealed an increase in the onset temperatures of decomposition for the treated composites. The dielectric investigation indicated that the samples containing olive pomace treated with the benzyl chloride can be used in electrical applications as insulators.
Ionic desorption in valence- and core- excited polymers: poly(vinyl chloride) and poly(vinylidene chloride)
Rocco, M. L. M.;Faraudo, G. S.;Pontes, F. C.;Souza, G. G. B. de;Pinho, R. R.;Ferreira, M.;
Brazilian Journal of Physics , 2006, DOI: 10.1590/S0103-97332006000400010
Abstract: photon stimulated ion desorption (psid) studies have been performed in poly(vinyl chloride) (pvc) and poly(vinylidene chloride) (pvdc) using synchrotron radiation, covering from valence to core electron (cl 2p and c 1s) energy ranges. data acquisition was performed at the tgm beam line from the brazilian synchrotron light source (lnls), operating in a multi-bunch mode and using a time-of-flight mass spectrometer (tof-ms). a new pulsed system developed uses as a trigger for the tof-ms experiments the pulsed extraction high voltage applied to the sample. ionic desorption from pvc and pvdc shows strong selectivity in the formation of chlorine ions around the cl 2p-edge while very similar fragmentation patterns are observed for the other energies studied.
Miscibility Behavior of Poly Ethylene Glycol or Poly Ethylene Succinate/Chlorinated Poly Vinyl Chloride Blends Studied by Dielectric Relaxation Spectroscopy  [PDF]
Taha A. Hanafy
Advances in Materials Physics and Chemistry (AMPC) , 2013, DOI: 10.4236/ampc.2013.32015
Abstract:

The miscibility of chlorinated poly vinyl chloride (CPVC) and poly ethylene glycol (PEG) or poly ethylene succinate (PES) had been investigated using dielectric relaxation spectroscopy (DRS) over frequency and temperature ranges; 10 kHz - 4 MHz and 300 - 450 K, respectively. Three relaxation processes namely ρ-, α’-, and α-relaxation processes were observed for tan(δ) and the electric modulus M\" of pure components and blends. The first one was attributed to the space charge polarization or the Maxwell-Wagner polarization. The second one was related to the amorphous regions located between the lamellar crystal stacks. The third one was due to the micro-Brownian motion of CPVC main chains. This process was found to be dependent in respect of temperature and frequency. The molecular dynamics of α-relaxation process were influenced by blending, i.e., the dielectric strength (De), the peak broadness, and the peak maximum of tan(δ) were found to be compositional dependent. Electric modulus analysis reveals that there is a role of electrode polarization for the dielectric relaxation.

Properties and Application of Nanocrystalline Poly (vinyl chloride)
Chuanxi XIONG,Hong YANG,Lijie DONG,Qihong LIU,Qingmin LIU,
Chuaaxi XIONG
,Hong YANG,Lijie DONG,Qihong LIU and Qingmin LIU School of Materials Science and Engineering,Wuhan University of Technology,Wuhan,China Shenzhen SPEC Plastics Holdings CO.,LTD,Shenzhen,China

材料科学技术学报 , 2004,
Abstract: The structure and properties of nanocrystalline PVC were investigated. The crystalline region of nanocrystalline PVC was observed by TEM to be 80 nm. The melting point of nanocrystalline PVC was found to be 128℃ which is obviously lower than typical PVC (210℃). The X-ray diagram indicated that the crystal existed in nanocrystalline PVC. The evident effect of self-plasticizing and reinforcement appeared when nanocrystalline PVC was added. The optimum amount for self-plasticizing is about 10%. The maximal impact strength of 95.1 kJ/m2 was achieved by adding 20% nanocrystalline PVC and tensile strength with 56.2 MPa which was 122% of pure PVC was obtained after adding 5% nanocrystalline PVC.
Influence of Poly(vinyl chloride) on Natural Rubber/Chlorosulfonated Polyethylene Blends  [PDF]
Manisara Phiriyawirut, Sawanya Luamlam
Open Journal of Organic Polymer Materials (OJOPM) , 2013, DOI: 10.4236/ojopm.2013.34013
Abstract:

Blend of natural rubber (NR) and chlorosulfonated polyethylene (CSM) was so interesting due to binding of the good oil resistance of CSM, the good mechanical properties and low cost of NR. However, due to the different polarities of two rubbers, phase separation and inferior properties of NR/CSM blend were obtained. The practical way to improve its properties is the addition of the third component to bind both phases of the blend. Effects of poly(vinyl chloride), PVC as compatibilizer on cure characteristics, morphology, mechanical properties and automotive fuel resistance of NR/ CSM blend were investigated. In this contribution, NR/CSM blend with blend ratio of 50/50 was prepared using a two-roll mill, and then vulcanized in a compression mold at 160°C. The PVC content was varied from 1 to 7 phr. It was found that the usage of 7 phr PVC led to improve interaction between NR and CSM phases. Therefore, increase in cure characteristics, mechanical strength and automotive fuel resistance of the blend was observed.

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