Chlorinated Polyethylene (CPE)

Polyvinyl chloride(PVC)has been blended with solid stated chlorinated polyethylene(CPE). The dependence of the compatibility of the blends on the mixing methods,chlorine content in CPE has been investigated.The dynamic mechanical analysis results showed that the PVC/CPE blends are partially compatible. The compatibility of the blends increases with increasing chlorine content in CPE and is affected by methods of blending. The CPE having continual segments showed a better compatibility with PVC. The morphology of the blends showed that CPEs are distributed on the surface of the PVC particle in a form of continual network.

Thermally stimulated creep measurements have been carried out on polyvinylchloride and on blends of polyvinylchloride with chlorinated polyethylenes of various chlorine distributions. Global spectra show that the two polymers are immiscible. However, a fine structure study of the spectra shows that some degree of compatibility exists in samples blended with randomly and commercially chlorinated polyethylenes. The same analysis leads to the conclusion that the sample blended with blocky chlorinated polyethylene is segregated into incompatible chlorinated polyethylene and polyvinylchloride phases.

THE EFFECTS OF IMPACT MODIFIERS ON THE PROCESSABILITY AND THE TOUGHNESS OF POLY VINYL CHLORIDE PROFILES . Extruded Poly Vinyl Chloride (PVC) door profile and window profiles often fail at the bend. This research aims to reduce such problem by enhancing the toughness of the PVC profiles while still maintaining their load bearing function and stiffness. Three impact modifiers namely methacrylate-butadiene-styrene (MBS), chlorinated polyethylene (CPE) and nano-scaled nitrile butadiene rubber (NBR) were employed in the PVC profiles at 1-11 phr. The processability assessed by rheometric study revealed only a slight increase in the torque required to process the melt PVC dosed with CPE and nano NBR while that required for the PVC with MBS was raised quite significantly. Although the PVC modified with MBS melted faster at a lower temperature, a rapid rise of temperature was observed during processing. The heat was probably due to the higher friction and shear induced by the rather viscous PVC melt dosed with MBS. Mechanical tests in terms of impact energy, stiffness and hardness revealed that the toughening efficiency of all three impact modifiers were close at low content, but at around 9 and 11 phr, the MBS and the CPE enhanced the impact energy quite rapidly by four folds while their corresponding hardness and stiffness were lowered considerably.

The effect of chlorinated polyethylene (CPE) content and test temperature on the notched Izod impact strength and brittle‐ductile transition behaviors for polyvinylchloride (PVC)/CPE blends and PVC/CPE/nano‐CaCO3 ternary composites is studied. The CPE content and the test temperature regions are from 0–50 phr and 243–363 K, respectively. It is found that the optimum nano‐CaCO3 content is 15 phr for PVC/CPE/nano‐CaCO3 ternary composites. For both PVC/CPE blends and PVC/CPE/nano‐CaCO3 ternary composites, the impact strength is improved remarkably when the CPE content or test temperature is higher than the critical value, that is, brittle‐ductile transition content (CBD) or brittle‐ductile transition temperature (TBD). The TBD is closely related to the CPE content, the higher the CPE content, the lower the TBD. The temperature dependence of impact strength for PVC/CPE blends and PVC/CPE/nano‐CaCO3 ternary composites can be well simulated with a logistic fitting model, and the simulation results can be illustrated with the percolation model proposed by Wu and Jiang. DMA results reveal that both PVC and CPE can affect the TBD of PVC/CPE blends and PVC/CPE/nano‐CaCO3 composites. When the CPE content is enough (20 phr), the CPE is more important than PVC for determining the TBD of PVC/CPE blends and PVC/CPE/nano‐CaCO3 composites. Scanning electron microscopy (SEM) observations reveal that the impact fractured mechanism can change from brittle to ductile with increasing test temperature for these PVC systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Polylauryllactam was used to improve the impact strength of polyvinylchloride (PVC)/chlorinated polyethylene (CPE) blends without sacrificing their tensile properties. The enhancement of the impact strength increased with the increase of the CPE content in the PVC/CPE blends due to the formation of intermolecular hydrogen bonds among PVC, polylauryllactam and CPE macromolecules. A doubled impact strength of the PVC/CPE blend with 20 weight percent of CPE was obtained after the addition of 1.5 phr polylauryllactam. The PVC/CPE blends with polylauryllactam have a better dimensional stability compared with the PVC/CPE blends without the additive, according to their viscoelastic characteristics. Polylauryllactam shortened the processing time to reach a minimum melt viscosity in the processing of the PVC/CPE blends.

Influence of chlorinated polyethylene on poly (vinyl chloride)/poly (α-methylstyrene-acrylonitrile) blends: Mechanical properties, morphology and thermal properties

This study seeks to substitute fumed silica for chlorinated polyethylene (CPE) within a rigid PVC formulation intended for profile extrusion such as doors and window frames. The effect of fumed silica on both mechanical (tensile and impact) and thermal (Vicat point, HDT, and linear thermal expansion coefficient) properties were investigated. Five rigid PVC formulations were prepared, including a reference one (F 1 ), then F 1 with CPE, F 1 with untreated silica, F 1 with heat treated silica, and finally F 1 with dried silica and a coupling agent. The effect of CPE on mechanical properties was very modest. On the other hand, CPE showed its inefficiency, in that HDT and Vicat point were decreased. Heat treated silica showed the greatest improvement in both mechanical and thermal properties. Untreated silica showed a small effect on both properties. Finally, the incorporation of coupling agent gave considerable improvement in both mechanical and thermal properties.

Preparation and properties of SAN/EPDM/CPE ternary blends

The results of experimental investigation into the mechanical properties of blends of low-density polyethylene (LDPE) with chlorinated polyethylene (CPE) in tension are presented. The specimens of pure LDPE, CPE, and nine types of LDPE/CPE blends, with different content of components at 10 wt.% intervals, were examined. Data on the influence of blend composition on the tensile stress-strain diagram, elastic modulus, yield stress, breaking stress, and ultimate elongation are obtained. The results of investigations of creep are also reported. It is found that the creep compliance (the total current compliance minus the elastic compliance) obeys the power law of creep.

Compatibilization of poly(vinyl chloride) and polyolefin elastomer blends with multiblock/blocky chlorinated polyethylenes

The blends of chlorinated polyethylene (CPE), ethylene-vinyl acetate copolymer (EVA) and nitrile rubber (NBR) were mixed and irradiated by electron beam. The effects of chlorinated polyethylene and electron irradiation on the structure and properties of blends were studied. The mechanical properties, crosslinking degree, crystallization properties, structure and morphology of EVA/NBR/CPE composites were characterized. The results showed that the addition of 25phr CPE had a significant effect on the capacity increase of EVA/NBR blend system, and the mechanical properties of the composites increased first and then decreased, the degree of crosslinking and the glass transition temperature increased while the crystallization temperature and enthalpy decreased. Electron beam irradiation induced hydrogen extraction reaction, formed a cross-linking structure, enhanced the phase interface bonding, and produced a synergistic effect with CPE volume-increasing EVA/NBR blend system.

The permeation resistance of chlorinated polyethylene (CPE) used in totally encapsulating chemical protective suits against the aerospace fuels hydrazine, monomethylhydrazine, and uns-dimethylhydrazine was determined by measuring the breakthrough time and time-averaged vapor transmission rate (VTR) using procedures consistent with ASTM Test Methods for Resistance of Protective Clothing to Permeation by Liquids or Gases Under Conditions of Continuous Contact (F 739) and Intermittent Contact (F 1383). Two exposure scenarios were simulated: a 2-hour (h) fuel vapor exposure, and a liquid fuel “splash” followed by a 2-h vapor exposure. To simulate internal suit pressure during operation, a positive differential pressure of 0.3 in. water (75 Pa) on the collection side of the permeation apparatus was used. A model was developed using the available data to estimate propellant concentrations inside an air-line fed, totally encapsulating chemical protective suit. Concentrations were calculated under simulated conditions of fixed vapor transmission rate, variable breathing airflow rate, and variable splash exposure area. Calculations showed that the maximum allowable permeation rates of hydrazine fuels through CPE were of the order of 0.10 ng cm-2 min-1 for encapsulating suits with breathing airflow rates of 5 to 9 scfm (140 to 255 L min-1). Above these permeation rates, the 10 parts per billion (ppb) threshold limit value-time weighted average could be exceeded. To evaluate suit performance at ppb-level concentrations, use of a sensitive analytical method such as cation exchange high performance liquid chromatography with amperometric detection, was found to be essential. The analytical detection limit determined the lowest measurable VTR, which in turn governed the lowest permeant concentration that could be calculated inside the totally encapsulating chemical protective suit.

The dynamic mechanical responses of rutile‐filled, chlorinated polyethylene (CPE) were studied as a function of temperature, of filler loading, and of filler surface condition. An objective was to establish the influence of matrix‐filler interactions on mechanical properties. Necessary information on potential interactions between matrix and filler was obtained from inverse gas chromatographic data, in the form of an acid‐base interaction parameter, Ω. The damping peak in filled CPE compounds was depressed by the pigment, as called for by theoretical models. The magnitude of the effect exceeded expectations, however, and clearly depended on the strength of interfacial interactions. These were consistent with the acid‐base ranking of CPE and the various rutiles, as given by Ω. It has been postulated that in the presence of acid‐base interactions, an immobilized layer of polymer in the vicinity of solid particles increases the effective particle dimension, thereby accounting for the observed variations in relative damping. Additional effects of matrix‐filler interaction were noted in the variation of storage moduli with loading and temperature. Again, the effects tend to be more pronounced when significant specific interactions between matrix and solid are operative. These observations point to the inadequacy of existing models as interpretative bases for dynamic mechanical properties in systems with significant specifie interactions among their components.

The increasing tendency to consider waste polymers as suitable stocks for reconversion calls for guidelines as to the processing and end‐product behavior of mixtures involving commodity polymers. In the present case, flow and some mechanical properties of mixtures involving low density polyethylene (PE) and filled polyvinyl chloride (PVC) were determined and used as a base‐line of comparison with similar properties of multi‐component mixtures involving potential compatibilizers for the incompatible matrix pair. Chlorinated polyethylene (CPE) ethylene‐vinyl acetate (EVA) copolymer and ELvaloy polymeric plasticizer were the property modifiers selected. Blends were produced by roll‐mill, Brabender or Banbury mixing. Flow properties were measured by capillary viscometry and solid‐state properties were characterized by stress‐strain data and tensile impact performance. Melt viscosities were non‐linear functions of blend composition and varied significantly with the choice of compatibiliser, EVA and CPE producing greater benefits of melt strength than did Elvaloy. Elastic moduli, ultimate tensiles and tensile impact data also responded to the presence of compatibiliser, the EVA and CPE again being more effective in upgrading the properties of the incompatible matrix pair than was Elvaloy. Results, while preliminary, suggest guidelines for the composition of PE/PVC stocks with upgraded performance balance.

The purpose of this study was to refine the Toronto Outcome Measure for Craniofacial Prosthetics (TOMCP), present evidence for its reliability and validity, and use the instrument to explore differences in quality of life between prostheses made with chlorinated polyethylene (CPE) (experimental) and silicone (control). As part of a multicenter prospective controlled randomized double-blind single-crossover clinical trial of the two materials, the TOMCP was administered at the start and end of two 4-month study arms, during which 42 patients wore prostheses made from one material then the other. Reliability was assessed at the crossover. To determine validity of the TOMCP, the Linear Analogue Self-Assessment (LASA-12) and the Short-Form 8 (SF-8) were also administered with the TOMCP. The TOMCP was reduced by removing items that were unreliable, had poorly distributed answers, showed increased internal consistency after their removal, or were too highly correlated with more than one other item. The tests of reliability and validity were then repeated. Finally, the reduced instrument was used to test for differences in quality of life between prostheses made of the two materials. The item reduction tactics pared the 52-item instrument down to 27 items. The correlations of both TOMCP versions with the LASA-12 and the SF-8 were found to be statistically significant, providing evidence of the validity of the TOMCP. The instrument revealed significantly better quality of life with silicone rather than CPE prostheses. Both versions of the TOMCP were found to be reliable and valid. The instrument was able to show differences in quality of life between two materials.