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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.

Utjecaj Ca/Zn stabilizatora na termooksidacijsku razgradnju mje avina poli(vinil-klorid)/klorirani polietilen / The effect of Ca/Zn stabilizers on the thermooxidative degradation poly(vinyl chloride) /chlorinated polyethylene blends
Nata?a STIPANELOV VRANDE?I?,Ivka KLARI?,Tonka KOVA?I?
Polimeri , 2006,
Abstract: Termooksidacijska razgradnja mje avina poli(vinil-klorida) (PVC) i polimernoga modifikatora kloriranoga polietilena (CPE) istra ivana je metodama diferencijalne pretra ne kalorimetrije i termogravimetrije u dinami kim i izotermnim uvjetima. Ustanovljeno je da istra ivani sastavi mje avina PVC-a i CPE-a (sadr aja klora 42 %) nisu mje ljivi. U temperaturnom podru ju od 50 do 650 oC termooksidacijska razgradnja mje avina zbiva se kroz dva temeljna razgradna stupnja. U prvome, do 400 oC, osnovne reakcije su dehidrokloriranje PVC-a i CPE-a, premda se brzine i mehanizam razgradnje polimera znatno razlikuju. Istra ivan je utjecaj Ca/Zn karboksilata razli itih omjera kalcija i cinka na toplinsku postojanost komponenata mje avine. Ca/Zn karboksilati stabiliziraju PVC mijenjaju i mu brzinu i mehanizam razgradnje, ali istodobno utje u i na razgradnju polimernoga modifikatora CPE-a. / The thermooxidative degradation of blends of poly(vinyl chloride) (PVC) and polymeric modifier chlorinated polyethylene (CPE) was investigated by means of differential scanning calorimetry (DSC) and thermogravimetry (TG) under dynamic and isothermal conditions. The immiscibility of PVC and CPE (chlorine content 42 %) was established for all the investigated compositions of the blends. The thermooxidative degradation of PVC/CPE blends in temperature range of 50 – 650 oC occurs in two basic degradation steps. In the first, up to 400 oC, the main degradation reactions are dehydrochlorination of PVC and CPE, but the rates and mechanisms of the polymer degradation are significantly different. The influence of Ca/Zn carboxylates with different Ca/Zn ratios, on thermooxidative stability of the blends components was also investigated. Ca/Zn carboxylates stabilize PVC by changing its degradation rate and mechanism, but, at the same time, these stabilizers influence the degradation of the polymeric modifier CPE.
INFRARED STUDY OF COMPATIBILITY OF POLYMER BLENDS: ETHYLENE-VINYL ACETATE COPOLYM- ER/POLY (VINYL CHLORIDE) OR CHLORINATED POLYETHYLENE
含氯聚合物和乙烯-醋酸乙烯酯共聚物共混体系的红外光谱研究

LU Yan,JING Xia-bin,JIANG Bing-zheng,FENG Zhi-liu,
卢琰
,景遐斌,姜炳政,冯之榴

高分子学报 , 1990,
Abstract: The compatibility in EVA/CPE or PVC was studied by IR spectroscopy. The frequency shifts of the carbonyl stretching vibration near 1739 cm-1 was examined as a function of VA content in EVA, Cl content in CPE(or PVC), blend composition and sample temperature.By comparing with model systems, such as EVA/CCl4, EVA/CHsCCl3 and EVA/CHCl3, the frequency shift observed for the blends was associated mainly with the hydrogen-bonding-like interaction between EVA and CPE (PVC). Based on the temperature dependence of the C = O frequency, the phase separation temperature and its dependence on blend composition were obtained for EVA(VA40%)/CPE(C164%) system.
Thermal Behavior with Mechanical Property of Fluorinated Silane Functionalized Superhydrophobic Pullulan/Poly(vinyl alcohol) Blends by Electrospinning Method  [PDF]
Mohammad Rezaul Karim,Md. Shahidul Islam
Journal of Nanomaterials , 2011, DOI: 10.1155/2011/979458
Abstract: Fluorinated silane functionalized superhydrophobic pullulan/poly(vinyl alcohol) (PULL/PVA) blend membrane with water contact angle larger than 150° has been prepared by the electrospinning method. The morphology, thermal stability, and mechanical property of the membranes are characterized using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and ZWICK materials testing machine, respectively. Interactions between PULL and PVA and PULL/PVA blends with perfluorooctyltriethoxysilane (PFOTES) of the membranes are analyzed using differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR). Contact angles and water drops on the surface of the membrane are measured by video microscopy. The study shows that the addition of minor quantity of PVA with PULL results in improvement in thermal stability and mechanical property (tensile strength) of the PULL membranes. 1. Introduction The wettability of a solid surface is an interesting property of a material and is described as the contact angle between a liquid and a solid surface. When the contact angle between water and a solid surface is larger than 150°, this solid surface is called a superhydrophobic surface [1]. Superhydrophobic surfaces are widely found in nature. For example, the surface of a lotus leaf is observed to be an array of nanoscale buds [2]. Water drops on the surface of the leaf tend to slide down, rendering its self-cleaning property. The surfaces which mimic “lotus effect” have triggered extensive interests for their potential applications involving water repellency, self-cleaning, and antifouling properties [3–6]. Generally, the hydrophobicity of surfaces depends on both their chemical composition and surface geometrical structure [7]. In terms of chemical composition, hydrophobicity can only be increased by introducing a component with low surface energy such as fluorinated methyl groups. However, this method to increase hydrophobicity is limited. The maximum contact angle that can be reached by coating fluorinated methyl groups onto a flat solid surface is only 120°, which can be hardly called superhydrophobic [8]. Therefore, a hierarchical structure is introduced into the solid surface to achieve superhydrophobicity. A number of methods have been used to make a hierarchical superhydrophobic surface including phase separation [9], electrochemical deposition [10], chemical vapor deposition [11], crystallization control [12], photolithography [13], assembly [14], sol-gel methods [15], solution-immersion methods [16], and array of nanotubes/nanofibers [17,
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.
Processing and Characterization of High Density Polyethylene/Ethylene Vinyl Acetate Blends with Different VA Contents  [PDF]
Othman Y. Alothman
Advances in Materials Science and Engineering , 2012, DOI: 10.1155/2012/635693
Abstract: Different series of high density Polyethylene/Ethylene Vinyl Acetate (HDPE/EVA) blends were prepared via melt blending in a corotating intermeshing twin screw extruder. The effects of VA percentage and EVA loading ratio on the thermal, rheological viscoelastic, mechanical, and fracture toughness of the blends were analyzed. The results showed that the addition of EVA to HDPE reduces the thermal, elastic, and viscoelastic properties of the blends. The microscopic examination of the fracture surface confirmed the ductile fracture of HDPE/EVA blends for all blend ratios and VA percentages. Increasing the EVA ratio and VA content caused a significant reduction in the blend crystallinity but had no significant effect on melting temperature. The complex viscosity increased with increasing the percentage of EVA due to the restriction of molecular mobility and reduction of free volume, induced by the addition of EVA. The storage modulus decreased with increasing the EVA ratio and temperature, while it increased with increasing the frequency. Young’s modulus, yield strength, and fracture strain decreased with increasing the EVA ratio. Similarly, the fracture toughness decreased proportional to the EVA percentage. Finally the results indicated that the VA content has significant effects on the mechanical, thermal, and dynamic properties of HDPE/EVA blends. 1. Introduction Polyethylene (PE) is being increasingly used in many industrial and biomedical applications. Its outstanding features such as regular chain structure, combination of low cost and low energy demand for processing, excellent biocompatibility, and good mechanical properties make PE expand its application continuously [1–5]. The superiority of PE products over metal products is attributed to their light weight, high corrosion resistance, and low costs. However, there are some drawbacks with Polyethylene including low environmental stress cracking resistance, low creep resistance, and poor compatibility with various additives which restricted its use for cretin purposes [6, 7]. Therefore, there have been many attempts to improve the properties of polyethylene by blending it with organic or inorganic materials [6–14]. Among these materials is Ethylene Vinyl Acetate (EVA) copolymer, a member of the polyolefin family derived from random copolymerization of Vinyl Acetate (VA) and Ethylene. EVA properties vary substantially as a function of VA content [5]. The VA content has two main effects on polyethylene (PE). First, increasing VA content decreases the crystallinity of PE. Although PE crystallinity
Non-isothermal crystallization kinetics of partially miscible ethylene-vinyl acetate copolymer/low density polyethylene blends
eXPRESS Polymer Letters , 2010, DOI: 10.3144/expresspolymlett.2010.19
Abstract: The non-isothermal crystallization kinetics of ethylene-vinyl acetate copolymer (EVA, 14 wt% vinyl acetate content), low density polyethylene (LDPE) and their binary blends with different blending ratio were investigated via differential scanning calorimetry. Jeziorny theory and Mo’s method were utilized in evaluating the crystallization behavior of both neat materials successfully. In the primary crystallization stage both EVA and LDPE had three-dimensional spherulitic growth mechanism. Apparently the crystallization rate of LDPE was faster than that of EVA at a low cooling rate. Increase in cooling rate limited the spherulites’ growth, which narrowed their rate difference. Influences from blending on the crystallization kinetics of each component in EVA/LDPE mixture were evaluated by Kissinger’s activation energy ( E) and Khanna’s crystallization rate coefficient (CRC). Inter-molecular interaction in the melt increased the E of both EVA and LDPE components at the beginning of cooling. During the primary crystallization stage of LDPE, dilution effect from EVA facilitated the crystal growth in LDPE. Co-crystallization between EVA component and the secondary crystallization stage of LDPE component also increased the CRC of EVA. In blend of EVA/LDPE = 7/3, LDPE obtained the maximal CRC value of 174.2 h–1. Results obtained from various approaches accorded well with each other, which insured the rationality of conclusion.
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.

Synthesis, characterization and photopolymerization of vinyl functionalized poly (ε-caprolactone)
eXPRESS Polymer Letters , 2009, DOI: 10.3144/expresspolymlett.2009.21
Abstract: Vinyl functionalized poly (ε-caprolactone) with molar mass ranging from 500–5000 Da were synthesized by ring opening polymerization and further photopolymerized. One-step synthesis and functionalization is achieved based on ring opening polymerization (ROP). Hydroxyl butyl vinyl ether (HBVE) was employed to play the role as the initiator of ROP, and photo-curable functional group. The presence of CH2=CH peak in Fourier Transform Infrared (FTIR) spectra confirmed that vinyl end groups were successfully attached to poly (ε-caprolactone) (PCL) macromolecule. Kinetic parameters of cationic photopolymerization of vinyl functionalized PCL were investigated. The activation energy was estimated at 11.33 kJ/mol, by assuming the cationic system followed second-order autocatalytic model.
Melt Rheology of Poly(Lactic Acid)/Low Density Polyethylene Polymer Blends  [PDF]
Kotiba Hamad, Mosab Kaseem, Fawaz Deri
Advances in Chemical Engineering and Science (ACES) , 2011, DOI: 10.4236/aces.2011.14030
Abstract: In this work, rheological properties of poly (lactic acid) (PLA), low density polyethylene (LDPE) polymer blends were investigated in the molten state. The experiments were carried on a capillary rheometer. The effect of shear stress, temperature and blending ratio on the flow activation energy at a constant shear stress and melt viscosity of the blends are described. The results showed that the PLA/LDPE polymer blends are pseudo plastic in nature, where there viscosity decreases with increasing shear stress. Also it was found the melt viscosity of the blends decreases with increasing PLA content in the blend.
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