Vinyl Chloride (vinyl + chloride)

Distribution by Scientific Domains

Selected Abstracts

An Efficient Bismuth(III) Chloride-Catalyzed Synthesis of 1,1-Diarylalkenes via Friedel,Crafts Reaction of Acyl Chloride or Vinyl Chloride with Arenes

Hongbin Sun
Abstract In the presence of catalytic amount of bismuth(III) chloride, the reactions of acyl chlorides or vinyl chlorides with arenes afforded 1,1-diarylalkenes in 25,82,% isolated yield. In the case of the reaction of acyl chlorides with arenes, the procedure includes an initial Friedel,Crafts acylation, subsequent formation of vinyl chlorides and final Friedel,Crafts-type vinylation of another arene molecule with vinyl chloride. This paper reports the first Lewis acid-catalyzed cleavage of the CCl bond of vinyl chloride and its application in the synthesis of multiply subtituted alkenes. [source]

Highly Efficient Synthesis of New ,-Arylamino-,,-chloropropan-2-ones via Oxidative Hydrolysis of Vinyl Chlorides Promoted by Calcium Hypochlorite

Vittorio Pace
Abstract The oxidative hydrolysis of different trifluoroacetyl-protected N -(2-chloroallyl)anilines, promoted by calcium hypochlorite, is able to yield several not previously described ,-arylamino-,,-chloropropan-2-ones, very valuable building blocks that are useful as precursors of several drugs, in excellent yields and short reaction times. The main requirement of the reaction for avoiding the undesired aromatic chlorination (N -protection) is effectively solved by the use of the easily formed and removed N -trifluoroacetyl group. Thus, it is possible to perform the oxidative hydrolysis-deprotection step using a one-pot strategy, obtaining quantitative yields in very short reaction times. [source]

Highly Active Palladium Catalysts Supported by Bulky Proazaphosphatrane Ligands for Stille Cross-Coupling: Coupling of Aryl and Vinyl Chlorides, Room Temperature Coupling of Aryl Bromides, Coupling of Aryl Triflates, and Synthesis of Sterically Hindered Biaryls

CHEMINFORM, Issue 19 2005
Weiping Su
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Palladium Catalyzed Amination of Vinyl Chlorides: A New Entry to Imines, Enamines and 2-Amino-1,3-butadienes.

CHEMINFORM, Issue 42 2004
Jose Barluenga
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Estimation of Ion-Pairing Constants in Plasticized Poly(vinyl chloride) Membranes Using Segmented Sandwich Membranes Technique

ELECTROANALYSIS, Issue 17-18 2009
Abstract Segmented sandwich membrane method was used to determine ion-pairing constants for four cationic sites: tris-(2,3,4-dodecyloxy)benzenetrimethylammonium, tris-(2,3,4-dodecyloxy)benzenedimethyloctylammonium, tris-(2,3,4-dodecyloxy)benzenemethyldioctylammonium, and dimethyldioctadecylammonium with chloride, bromide, nitrate, benzene sulfonate, trichloroacetate, thiocyanate, perchlorate and picrate, as well as ion-pairing constants for two anionic sites: tetraphenylborate and tris-(2,3,4-octyloxy)benzenesulfonate with dimedrol, quinine, anapriline, and amantadine cations in poly(vinyl chloride) membranes plasticized with 2-nitrophenyl octyl ether. Ion association constants of anions with quaternary ammonium sites regularly increase from picrate to chloride along with reduction of the anion radius and with improvement of site exchanger center steric accessibility. Ion association constants of amine cations with tris-(2,3,4-octyloxy)benzenesulfonate are several orders higher than those with tetraphenylborate and regularly increase from tertiary amine to primary one. [source]

Novel Thorium Membrane Sensors with Anionic Response Based on Trioctylphosphine Oxide and Toluate Ionophores


Abstract Two novel potentiometric polymeric membrane sensors for rapid and accurate determination of thorium are described. These are based on the use of trioctylphosphine oxide (TOPO) and thorium toluate (Th-TA) as ionophores dispersed in poly(vinyl chloride) matrix membranes plasticized with nitrophenyloctyl ether. In strong nitric acid medium, Th(IV) nitrate is converted into [Th(NO3)6]2, complex and sensed as anionic divalent ion which exclude most cationic effect. Validation of the assay methods using the quality assurance standards (linearity range, accuracy, precision, within-day variability, between-day-repeatability, lower detection limit and sensitivity) reveals excellent performance characteristics of both sensors. The sensors exhibit near-Nernstian response for 1.010,6,1.010,1 M Th over the pH range 2.5,4.5. Calibration slopes of ,32.30.3 and ,27.20.2,mV/decade, precision of 0.5 and 0.8% and accuracy of 98.80.9 and 97.90.7% are obtained with TOPO and Th-TA based sensors, respectively. Negligible interferences are caused by most interfering mono-, di-, tri-, tetra-, penta-, and hexa-valent elements commonly associated with thorium in naturally occurring minerals and ores. High concentrations of Cl,, F,, SO42,, and NO3, ions have no diverse effect. Complete removal of the effect of the interferents in complex matrices is achieved by retention of [Th(NO3)6]2, complex from 5,M nitric acid/methanol mixture (1,:,9,v/v) on a strong anion exchanger, washing out the cationic interferents followed by stripping off thorium anion complex and measurements. Both sensors are used for determining thorium in certified thorium ore samples (20,120,mg Th/kg) and some naturally occurring ores (200,600,mg Th/kg). The results obtained agree fairly well with the certified labeled values or the data obtained using X-ray fluorescence spectrometry [source]

Development of a Novel Automatic Potentiometric System for Determination of Selenium and Its Application in Pharmaceutical Formulations and Anodic Slime

Abstract Poly(vinyl chloride) polymeric membrane sensors containing Sn(IV) phthalocyanine dichloride (SnPC) and Co(II) phthalocyanine (CoPC) as novel electroactive materials dispersed in o -nitrophenyl octylether (o -NPOE) as a plasticizer are examined potentiometrically with respect to their response toward selenite (SeO32,) ions. Fast Nernstian response for SeO32, ions over the concentration ranges 7.010,6,1.010,3 and 8.010,6,1.010,3 mol L,l at pH,3.5,8.5 with lower detection limit of 5.010,6 and 8.010,6 mol L,1 and calibration slopes of ,25.4 and ,29.7,mV decade,1 are obtained with SnPC and CoPC based membrane sensors, respectively. The proposed sensors reveals by the modified separate solution method (MSSM) a good selectivity over different anions which differ significantly from the classical Hofmeister series. A segmented sandwich membrane method is used to determine complex formation constants of the ionophores in situe in the solvent polymeric sensing membranes. Membrane incorporating CoPC in a tubular flow detector is used in a two channels flow injection set up for continuous monitoring of selenite at a frequency of ca. 50 samples h,1. Direct determination of selenium in pharmaceutical formulations and anodic slime gives results in good agreement with data obtained using standard ICP method. [source]

Comparative Studies of Tridentate Sulfur and Nitrogen-Containing Ligands as Ionophores for Construction of Cadmium Ion-Selective Membrane Sensors

Ashok, Kumar Singh
Abstract New polymeric membrane cadmium-ion selective sensors have been prepared by incorporating nitrogen and sulfur containing tridentate ligands as the ionophores into the plasticized PVC membranes. Poly(vinyl chloride) (PVC) based membranes of potassium hydrotris[N -(2,6-xylyl)thioimdazolyl) borate] (KTt2,6-xylyl) and potassium hydrotris(3-phenyl-5-methylpyrazolyl) borate (KTpPh,Me) with sodium tetraphenyl borate (NaTPB) as an anionic excluder and dibutylphthalate (DBP), tributylphthalate (TBP), dioctylsebacate (DOS), and o -nitrophenyloctyl ether (o -NPOE) as plasticizing solvent mediators were investigated in different compositions. KTt2,6-xylyl was found to be a selective and sensitive ion carrier for Cd(II) membrane sensor. A membrane composed of KTt2,6-xylyl:NaTPB:PVC:DBP with the % mole ratio 2.3,:,1.1,:,34.8,:,61.8 (w/w) works well over a very wide concentration range (7.810,8,1.010,2,M) with a Nernstian slope of 29.40.2,mV/decades of activity between pH values of 3.5 to 9.0 with a detection limit of 4.3710,8,M. The sensor displays very good discrimination toward Cd(II) ions with regard to most common cations. The proposed sensor shows a short response time for whole concentration range (ca. 8,s). The effects of the cationic (tetrabutylammonium chloride, TBC), anionic (sodium dodecyl sulfate, SDS) and nonionic (Triton X-100) surfactants were investigated on the potentiometric properties of proposed cadmium-selective sensor. The proposed sensor based on KTt2,6-xylyl ionophore has also been used for the direct determination of cadmium ions in different water samples and human urine samples. [source]

Galvanostatic Polarization of All-Solid-State K+ -Selective Electrodes with Polypyrrole Ion-to-Electron Transducer

ELECTROANALYSIS, Issue 13-14 2006
Abstract Influence of galvanostatic polarizations on potential vs. logarithm of ion activity dependences of all-solid-state ion-selective electrodes with conducting polymer ion-to-electron transducer was studied. As a model system K+ -sensor with polypyrrole solid contact and poly(vinyl chloride) based membrane containing valinomycin was chosen. The influence of the lipophilic salt included to the membrane composition was of special interest. [source]

Iodide-Selective Electrode Based on Copper Phthalocyanine

Saeed Shahrokhian
Abstract Copper phthalocyanine was used as ion carrier for preparing polymeric membrane selective sensor for detection of iodide. The electrode was prepared by incorporating the ionophore into plasticized poly(vinyl chloride) (PVC) membrane, coated on the surface of graphite electrode. This novel electrode shows high selectivity for iodide with respect to many common inorganic and organic anions. The effects of membrane composition, pH and the influence of lipophilic cationic and anionic additives and also nature of plasticizer on the response characteristics of the electrode were investigated. A calibration plot with near-Nernestian slope for iodide was observed over a wide linear range of five decades of concentration (510,6,110,1,M). The electrode has a fast response time, and micro-molar detection limit (ca. 110,6,M iodide) and could be used over a wide pH range of 3.0,8.0. Application of the electrode to the potentiometric titration of iodide ion with silver nitrate is reported. This sensor is used for determination of the minute amounts of iodide in lake water samples. [source]

Aerobic biodegradation of the chloroethenes: pathways, enzymes, ecology, and evolution

Timothy E. Mattes
Abstract Extensive use and inadequate disposal of chloroethenes have led to prevalent groundwater contamination worldwide. The occurrence of the lesser chlorinated ethenes [i.e. vinyl chloride (VC) and cis -1,2-dichloroethene (cDCE)] in groundwater is primarily a consequence of incomplete anaerobic reductive dechlorination of the more highly chlorinated ethenes (tetrachloroethene and trichloroethene). VC and cDCE are toxic and VC is a known human carcinogen. Therefore, their presence in groundwater is undesirable. In situ cleanup of VC- and cDCE-contaminated groundwater via oxidation by aerobic microorganisms is an attractive and potentially cost-effective alternative to physical and chemical approaches. Of particular interest are aerobic bacteria that use VC or cDCE as growth substrates (known as the VC- and cDCE-assimilating bacteria). Bacteria that grow on VC are readily isolated from contaminated and uncontaminated environments, suggesting that they are widespread and influential in aerobic natural attenuation of VC. In contrast, only one cDCE-assimilating strain has been isolated, suggesting that their environmental occurrence is rare. In this review, we will summarize the current knowledge of the physiology, biodegradation pathways, genetics, ecology, and evolution of VC- and cDCE-assimilating bacteria. Techniques (e.g. PCR, proteomics, and compound-specific isotope analysis) that aim to determine the presence, numbers, and activity of these bacteria in the environment will also be discussed. [source]

Fire hazard evaluation of thermoplastics based on analytic hierarchy process (AHP) method

Baogang Yu
Abstract Combustibility performance of 14 compositions including five main thermoplastics (polycarbonate (PC), polypropylene (PP), high impact polystyrene (HIPS), acrylonitrile butadiene styrene (ABS) and poly (vinyl chloride) (PVC)) was tested by cone calorimeter. The fire growth index, total heat release amount index, total smoke release amount index and toxicity product index were calculated, based on which an index system for evaluating fire hazard was set up. All factors in this index system had been analyzed by the analytic hierarchy process, and the specific weight for each factor had been determined. Then fire hazard of thermoplastics was evaluated considering integrated fire hazard index. The results show that fire hazards of HIPS-phosphate fire retardant (PFR), PVC-non-flame retardant, ABS-brominated flame retardant (BFR) and PC/ABS-PFR are higher than PC-BFR and PP-non-halogenated flame retardant. Copyright 2009 John Wiley & Sons, Ltd. [source]

Zinc hydroxystannate-coated metal hydroxides as flame retardant and smoke suppression for flexible poly vinyl chloride

Hongqiang Qu
Abstract Zinc hydroxystannate (ZHS)-coated metal hydroxides were prepared. The effects of ZHS-coated metal hydroxides on flame retardancy and smoke suppression of flexible poly vinyl chloride were studied by means of the limiting oxygen index, smoke density rating and the char yield test. The mechanism was investigated by thermogravimerty (TG), differential thermal analysis, and differential TG analysis and scanning electron microscopy. The results showed that ZHS-coated metal hydroxides are more effective flame retardant and smoke suppressant than metal hydroxides, and it appears that tin compound may exert its action in both the condensed and vapor phases, but mainly in condensed phases as a Lewis acid. Copyright 2009 John Wiley & Sons, Ltd. [source]

Cone calorimeter analysis of UL-94 V-rated plastics,

Alexander B. Morgan
Abstract Cone calorimeter analysis was conducted on 18 thermoplastics with different UL-94 vertical burn test (V) ratings. Ratings varied from V-0 to no rating (NR), and the types of thermoplastics included were polycarbonate (PC), acrylonitrile,butadiene,styrene (ABS), PC/ABS blends, high-impact polystyrene (HIPS), polypropylene (PP), and poly(vinyl chloride) (PVC). Our analysis of the cone calorimeter data found that there were correlations between UL-94 V rating and some cone calorimeter measurements (peak heat release rate (HRR) average and HRR at 60 s) and no relationship for other measurements (time to ignition and total heat release). However, no precise correlation was found due to significant differences in flame retardant mechanism and polymer fuel energy values. In this paper, we seek to explain further why a broad quantitative relationship between UL-94 V and cone calorimeter remains elusive, and also to show how the cone calorimeter can be used to understand why a material passes or fails a particular UL-94 V rating. Copyright 2006 John Wiley & Sons, Ltd. [source]

Trichlorofluoroethene: A reactive tracer for evaluating reductive dechlorination in large-diameter permeable columns

Jennifer A. Field
Trichlorofluoroethene (TCFE) was used as a reactive tracer to determine the in situ rate of reductive dechlorination in treatment zones impacted by three large-diameter permeable columns (LDPCs) that were installed at a trichloroethene (TCE),contaminated site. The LDPCs were part of a pilot study to evaluate the effectiveness of hydrogen, lactate, and zero-valent iron for remediating TCE-contaminated ground water. The rate of TCFE reductive dechlorination was determined for each LDPC by means of push-pull tests conducted in each treatment layer. In addition, the distribution of TCFE's lesser chlorinated transformation products was determined. The rates of TCFE reductive dechlorination ranged from 0.05/d to 0.20/d and corresponded to half-lives ranging from 3.5 to 13.9 d. cis -Dichlorofluoroethene was the dominant transformation product detected in all the tests, which is consistent with the findings from pilot tests conducted in the LDPCs prior to the TCFE push-pull tests. cis -Chlorofluoroethene (CFE) and 1,1-CFE also were detected and indicate the potential for vinyl chloride to form under all treatment regimes. Significant production of fluoroethene (FE), the analog of ethene, was observed for only one of the hydrogen treatments. Unambiguous and sensitive detection of the lesser chlorinated products, such as CFE and FE, is possible because TCFE and its transformation products are not found in the background ground water at contaminated sites. Good agreement between the rates and transformation product profiles for TCFE and TCE in both field and laboratory experiments indicates the suitability of TCFE as a surrogate for predicting the rates of TCE reductive dechlorination. [source]

Comparative study of kinetics and reactivity indices of free radical polymerization reactions,

K. Van Cauter
Abstract Density functional theory calculations are used to determine the kinetics and reactivity indices of the first propagation steps of the polyethylene and poly(vinyl chloride) polymerization. Transition state theory is applied to evaluate the rate coefficient from the microscopically determined energies and partition functions. A comparison with the experimental Arrhenius plots validates the level of theory. The ability of reactivity indices to predict certain aspects of the studied propagation reactions is tested. Global softnesses of the reactants give an indication of the relative energy barriers of subsequent monomer additions. The correlation between energy and hardness profiles along the reaction path confirm the principle of maximum hardness. Local indices predict the regioselectivity of the attack of the growing radical to vinyl chloride. 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source]

An Efficient Bismuth(III) Chloride-Catalyzed Synthesis of 1,1-Diarylalkenes via Friedel,Crafts Reaction of Acyl Chloride or Vinyl Chloride with Arenes

Hongbin Sun
Abstract In the presence of catalytic amount of bismuth(III) chloride, the reactions of acyl chlorides or vinyl chlorides with arenes afforded 1,1-diarylalkenes in 25,82,% isolated yield. In the case of the reaction of acyl chlorides with arenes, the procedure includes an initial Friedel,Crafts acylation, subsequent formation of vinyl chlorides and final Friedel,Crafts-type vinylation of another arene molecule with vinyl chloride. This paper reports the first Lewis acid-catalyzed cleavage of the CCl bond of vinyl chloride and its application in the synthesis of multiply subtituted alkenes. [source]

Metallic oxides as fire retardants and smoke suppressants in flexible poly(vinyl chloride)

Antonio Rodolfo Jr.
Abstract Combustion and smoke emission properties of PVC compounds, modified with copper (II), molybdenum, and zinc oxides, were studied using cone calorimeter, limiting oxygen index (LOI) and thermogravimetry coupled with mass spectrometry (TG/MS). Results showed that the metal oxides have a very significant effect on the combustion and smoke suppression properties of the PVC compounds. The results also confirmed the anticipation mechanisms of the dehydrochlorination reactions, reductive coupling, and elimination of benzene resulting from the presence of copper (II), molybdenum, and zinc, indicated by the increasing content of postcombustion char residue and the significant reduction in benzene production, indicated by the MS measurements performed. The results also provide indications that the combination of the copper (II) and molybdenum oxides is the one with the best balance of combustion properties, as it reduced the heat released and promoted the suppression of smoke more efficiently. The formulations containing ZnO, because of their strong Lewis acid character, indicated a less pronounced reduction of smoke released during the combustion process, when compared with copper (II) and molybdenum oxides. 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

Investigation of the phase morphology of dynamically vulcanized PVC/NBR blends using atomic force microscopy

S. M. Gheno
Abstract Dynamic vulcanization is a mixing process employed in the melt state of elastomers with thermoplastics. This process may result in the formation of thermoplastic vulcanized (TPV) materials with improved properties such as mechanical strength, Young's modulus, hardness, and abrasion fatigue. In this study, a vulcanized thermoplastic was obtained by the dynamic vulcanization of poly(vinyl chloride)/acrylonitrile butadiene rubber (PVC/NBR) blends using a curative system based on sulfur (S)/tetramethylthiuram disulfide (TMTD) and mercaptobenzothiazyl disulfide (MBTS). The formation of crosslinks was characterized by differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The mechanical properties were analyzed by tensile tests and the phase morphology was investigated using atomic force microscopy (AFM) operating in the tapping mode-AFM. The phase images of the dynamically vulcanized blends showed an elongated morphology, which can be associated to the formation of crosslinks that give the material its excellent mechanical properties. 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

A novel route for preparation of PVC sheets with high UV irradiation resistance

Xianke Ye
Abstract A novel acrylonitrile acrylate copolymer coating was proposed to improve the UV irradiation resistance of poly(vinyl chloride) (PVC) sheets. Its effect on the photoageing properties of the sheets was evaluated by means of Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), yellowness index test, and the oxygen permeability coefficient and mechanical properties measurement. The experimental results show that the novel acrylonitrile acrylate copolymer coating significantly improves the UV irradiation resistance of PVC sheets. Compared with the PVC sheets without coating, the coated PVC sheets show better mechanical properties, lower yellowness index, and smaller oxygen permeability coefficient after UV irradiation. The analysis on the SEM images of the PVC sheets indicates that the coating acts as a film to prevent the PVC sheets from UV energy and oxygen that can accelerate the photochemical reactions of PVC. The FTIR analysis confirms that the coating can slow down the microstructures development of the PVC sheets, also indicating that the coating impeded the photochemical reactions of PVC. 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

Mechanical and morphological properties for sandwich composites of wood/PVC and glass fiber/PVC layers

Narudol Mongkollapkit
Abstract This work manufactured sandwich composites from glass fiber/poly(vinyl chloride) (GF/PVC) and wood/PVC layers, and their mechanical and morphological properties of the composites in three GF orientation angles were assessed. The effects of K value (or viscosity index) of PVC and Dioctyl phthalate (DOP) loading were of our interests. The GF/PVC was used as core layer whereas wood/PVC was the cover layers. The experimental results indicated that PVC with low K value was recommended for the GF/PVC core layer for fabrication of GF/WPVC sandwich composites. The improvement of PVC diffusion at the interface between the GF and the PVC core layer was obtained when using PVC with K value of 58. This was because it could prevent de-lamination between composite layers which would lead to higher mechanical properties of the sandwich composites, except for the tensile modulus. The sandwich composites with 0 GF orientation possessed relatively much higher mechanical properties as compared with those with 45 and 90 GF orientations, especially for the impact strength. Low mechanical properties of the sandwich composites with 45 and 90 GF orientation angles could be overcome by incorporation of DOP plasticizer into the GF/PVC core layer with the recommended DOP loadings of 5,10 parts per hundred by weight of PVC components. 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

Mechanochemical preparation of a novel polymeric photostabilizer for poly(vinyl chloride)

Xiaofei Zhang
Abstract The preparation of a novel polymeric photostabilizer was carried out via the vibromilling of poly(vinyl chloride) (PVC) powder, a reactive light stabilizer (r-LS), and a peroxide initiator in ball-containing jars with a planetary ball mill for a certain time. The effects of the initiator content, milling time, and temperature on the grafting ratio were studied with gravimetric analysis and intrinsic viscosity measurements. Fourier transform infrared and ultraviolet,visible spectra were used to investigate the structural development of the mixture of the r-LS and PVC during vibromilling. The results showed that the r-LS was grafted onto PVC chains successfully, and the aforementioned factors had a significant effect on the grafting ratio. The optimum preparation conditions were 0.5 wt % initiator, 8 h, and 20C. A grafting mechanism is proposed. 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

Effect of acrylic core,shell rubber particles on the particulate flow and toughening of PVC

M. 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]

Behavior of flexible poly(vinyl chloride)/poly(hydroxybutyrate valerate) blends

A. Marcilla
Abstract Blends of flexible poly(vinyl chloride) (PVC) and a poly(hydroxybutyrate valerate) (PHBV) copolymer were prepared and characterized with different techniques. The tensile strength of PVC did not show a marked reduction at PHBV concentrations up to 50 phr, despite a lack of miscibility between the two polymers. The crystallization of the PHBV copolymer was markedly hindered by the presence of PVC, as calorimetric results revealed. 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]

Thermal degradation behavior of poly(vinyl chloride) in the presence of poly(glycidyl methacrylate)

Magdy W. Sabaa
Abstract The thermal degradation behavior of poly(vinyl chloride) (PVC) in presence of poly(glycidyl methacrylate) (PGMA) has been studied using continuous potentiometric determination of the evolved HCl gas from the degradation process from one hand and by evaluating the extent of discoloration of the degraded samples from the other. The efficiency of blending PGMA with dibasic lead carbonate (DBLC) conventional thermal stabilizer has also been investigated. A probable radical mechanism for the effect of PGMA on the thermal stabilization of PVC has been suggested based on data reported by FTIR and elemental analyses. 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]

The structure and dynamic properties of nitrile,butadiene rubber/poly(vinyl chloride)/hindered phenol crosslinked composites

Ping 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]

Effects of epoxidized sunflower oil on the mechanical and dynamical analysis of the plasticized poly(vinyl chloride)

Badra Bouchareb
Abstract Epoxidized soybean oil (ESBO), is one of the most commonly used epoxides because of its typical combined roles as a plasticizer and heat stabilizer. In this study, a novel plasticizer of poly(vinyl chloride) (PVC) resins, epoxidized sunflower oil (ESO), was synthesized, and its performance was evaluated. ESO was designed to act as a coplasticizer and a heat stabilizer like ESBO. ESO is used as organic coplasticizer for plasticized PVC containing Ca and Zn stearates as primary stabilizers and stearic acid as lubricant. Di-(2-ethylhexyl) phthalate (DEHP), a conventional plasticizer for PVC, was partially replaced by ESO. Mechanical properties (tensile and shore D hardness) were investigated. The performance of ESO to ESB0 (20 g) for comparison, indicated that ESO could be used as secondary plasticizer for PVC in combination with DEHP. All mechanical and dynamical properties of plasticized PVC sheets varied with the oxirane oxygen of the ESO. 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]

Compatibility study of recycled poly(vinyl chloride)/styrene-acrylonitrile blends

David Garcia
Abstract The aim of the present study is to analyze the compatibility between recycled Poly(vinyl chloride) (PVC) and styrene-acrylonitrile copolymer (SAN). With this objective recycled PVC coming from credit cards have been blended with both virgin and recycled SAN with the aim of increase the benefits of recycled PVC. The compatibility of the components will be crucial for the final properties of the material. Furthermore, the recycled nature of some of the components will determine the compatibilization capability of the blend. The degradation level in the recycled materials was determined using Fourier transform infrared spectroscopy (FTIR). The compatibility between the PVC and the SAN was studied using differential scanning calorimetry and dynamic mechanical analysis. A greater compatibility was observed in mixtures of PVC and virgin SAN than in mixtures of PVC and recycled SAN. Finally, a morphological study of the fracture surface under cryogenic conditions was carried out using scanning electron microscopy. 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source]

Miscibility and rheological properties of poly(vinyl chloride)/styrene,acrylonitrile blends prepared by melt extrusion

Hyun Sik Moon
Abstract Styrene,acrylonitrile (SAN) with acrylonitrile (AN) concentrations of 11.6,26 wt % and ,-methylstyrene acrylonitrile (,MSAN) with a wide range of AN concentrations are miscible with poly(vinyl chloride) (PVC) through solution blending. Here we examine the rheological properties and miscibility of PVC/SAN and PVC/,MSAN blends prepared by melt extrusion for commercial applications. We have investigated the rheological properties of the blends with a rheometer and a melt indexer. The PVC/SAN and PVC/,MSAN blends have a low melting torque, a long degradation time, and a high melt index, and this means that they have better processability than pure PVC. The miscibility of the blends has been characterized with differential scanning calorimetry, dynamic mechanical thermal analysis, and advanced rheometrics expansion system analysis. The miscibility of the blends has also been characterized with scanning electron microscopy. The SAN series with AN concentrations of 24,31 wt % is immiscible with PVC by melt extrusion, whereas ,MSAN with 31 wt % AN is miscible with PVC, even when they are blended by melt extrusion, because of the strong interaction between PVC and ,MSAN. 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source]

Blends of triazine-based hyperbranched polyether with LDPE and plasticized PVC

Jyotishmoy Borah
Abstract Triazine-based hyperbranched polyether was obtained by earlier reported method and blended with low density polyethylene (LDPE) and plasticized poly(vinyl chloride) (PVC) separately to improve some desirable properties of those linear polymers. The properties like processability, mechanical properties, flammability, etc. of those linear polymers were studied by blending with 1,7.5 phr of hyperbranched polyether. The mechanical properties were also measured after thermal aging and leaching in different chemical media. SEM study indicates that both polymers exhibit homogenous morphology at all dose levels. The mechanical properties like tensile strength, elongation at break, hardness, etc. of LDPE and PVC increase with the increase of dose level of hyperbranched polyether. The flame retardant behavior as measured by limiting oxygen index (LOI) for all blends indicates an enhanced LOI value compared to the polymer without hyperbranched polyether. The processing behavior of both types of blends as measured by solution viscosity and melt flow rate value indicates that hyperbranched polyether acts as a process aid for those base polymers. The effect of leaching and heat aging of these linear polymers on the mechanical properties showed that hyperbranched polyether is a superior antidegradant compared to the commercially used N -isopropyl- N -phenyl p -phenylene diamine. 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 648,654, 2007 [source]