Properties and morphology of poly(vinyl chloride) blends with solid‐state‐chlorinated polyethylene

Correlations of the stress‐strain behavior and impact strength of poly(vinyl chloride) (PVC) blends with different amounts and chlorine contents of solid‐state‐chlorinated polyethylene (CPE) were studied. The relationships between the morphology and properties of the PVC/CPE blends also were investigated. The results of dynamic mechanical analysis and transmission electron microscopy showed that PVC/CPE blends are partially compatible systems and that a certain interaction exists between the two phases. When the amount of CPE (chlorine content, 36–42%) was 7–15 phr (parts by weight per hundred parts of resin), an essentially perfect CPE network was formed, and the blends showed better impact resistance. A Brabender Plasticorder study revealed that CPE can promote the plasticity of PVC and improve its processability. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers     

Properties of chlorinated polyvinyl chloride

By chlorination of polyvinyl chloride in a water suspension, a number of samples of chlorinated polyvinyl chloride of varied chlorine content were prepared. The density, the temperature dependence of the dynamic modulus G' and the loss factor tg δ, as well as some mechanical properties of these samples were measured. The structure of the chlorinated PVC is discussed and the assumption expressed that the secondary maximum at ? 10°C corresponds to the movements of the short chain interceptions of poly (1,2-dichloroethylene). The tensile strength and flexural strength is growing linearly with the chlorine content. The impact strength from 65% Cl on is violently decreasing. By its behaviour, chlorinated polyvinyl chloride resembles a random copolymer of vinyl chloride and 1,2-dichloroethylene.     

Graft‐modified HCPE with methyl methacrylate by the mechanochemistry reaction. II. Physical‐mechanical properties and processability

In this article, the physical‐mechanical properties and processability of graft‐modified highly chlorinated polyethylene (HCPE; chlorine contents: ≥ 60%) with methyl methacrylate (MMA) by mechanochemistry reaction were studied. The results showed that the HCPE‐g‐MMA system is superior to unmodified HCPE in physical‐mechanical properties, particularly in processability. In addition, the HCPE‐g‐MMA system, with about 62% chlorine content, was the same as PVC in its physical‐mechanical properties. The HCPE‐g‐MMA system, with about 65.5% chlorine content, is the same as chlorinated poly(vinyl chloride) (CPVC) in its physical‐mechanical properties, except that the Vicat softening temperature and processability of HCPE‐g‐MMA system are superior to PVC and CPVC. Compared with PVC and CPVC, the HCPE‐g‐MMA system proves better due to its lack of a toxic monomer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 282–287, 2004     

固相法氯化聚乙烯与聚氯乙烯共混物的形态与性能

研究了聚氯乙烯(PVC)与固相法氯化聚乙烯(CPE)共混物的应力-应变行为和冲击强度对CPE用量和氯含量的依赖关系,考察了共混物形态与性能的关系。动态力学性能和透射电子显微镜的研究结果表明,PVC/CPE为部分相容体系,两相间存在着一定的相互作用,当CPE氯含量为36％～42％,用量为7～15份时,CPE在PVC/CPE共混物中形成比较完整的网络结构、共混物具有更好的抗冲击性能。Brabender流变仪研究表明,CPE能促进PVC的塑化,共混物的加工性优于纯PVC。     

Impact modification of poly(vinyl chloride) with chlorinated polyethylene I. Blend morphology

The solid state morphology of chlorinated polyethylene (CPE)-modified poly(vinyl chloride) (PVC) and the relationship of blend structure to impact strength and mode of fracture have been investigated. Selective staining of the CPE phase showed that the morphology of the two phase system changes with increasing CPE content from a dispersion of discrete CPE particles to a network structure enveloping the primary PVC particles. The network formation coincides with a transition from brittle to ductile impact fracture. When the blend was mixed for too long a time or above the fusion temperature of the primary PVC particles, the CPE network was destroyed. The resulting indistinct domain structure is associated with a reduction in the impact properties.     

Solubility parameters and some structural characteristics of chlorinated poly(vinyl chloride)

Measurements of solubility parameters of a series of chlorinated poly(vinyl chloride) (CPVC) samples were carried out. A maximum value of solubility parameter occurs at a chlorine content of 63–65% and is related to optimum packing.     

Blends of poly(vinyl chloride) with acrylonitrile-chlorinated polyethylene-styrene copolymer. II. Mechanical properties

Blends of poly(vinyl chloride) (PVC) and acrylonitrile-chlorinated polyethylene-styrene (ACS) graft copolymer were prepared by melt blending. Mechanical properties were studied by the use of dynamic mechanical analysis (DMA), impact tests, tensile tests, and scanning electron microscopy (SEM). The DMA study showed that PVC is immiscible with chlorinated polyethylene in ACS but partially miscible with poly(styrene-co-acrylonitrile) (25% acrylonitrile content) in ACS. Mechanical property tests showed that there is a significant increase in the impact strength while other good mechanical properties of PVC such as high modulus and high strength remain. SEM observations supported the results of the mechanical properties studies. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 399–405, 1997     

抑制PVC制品中小分子增塑剂迁移的研究

采用气-固相氯化法和氯化原位接枝法对小分子增塑剂邻苯二甲酸二辛酯(DOP)进行了改性,得到的产物分别与PVC共混,并对其失重率、沸点、力学性能进行了研究。结果表明:氯含量为30%左右的氯化DOP,从PVC制品表面迁移出来的几率最小;DOP氯化原位接枝丙烯酸丁酯(BA)后作为PVC的增塑剂,当BA含量在1～10份时材料的失重较少,而BA含量在10份时材料的强度及韧性最好。     

A study on poly(vinyl chloride) blends with chlorinated polyethylene and acrylic resin

The compatibility, morphology, fusion behavior, and mechanical properties of blends of poly(vinyl chloride) (PVC), acrylic resin (ACR), and chlorinated polyethylene (CPE) (100/0–30/0–20) were studied. The experimental results show that the compatibility of the polyblend increases with the amount of ACR added. The blends composed of PVC/ACR/CPE (100/3–25/10–15) are fairly compatible. So far as impact strength is concerned, partially compatible blends are preferred.     

Modification of polyolefin films by photochlorination

Composite polyolefin membranes with graded chlorination gradient were obtained by photochlorination of polyethylene, polypropylene, and polystyrene films using ultraviolet and visible light. The maximum chlorine contents of these membranes were 12%, 8.5%, and 6.5%, respectively. As for polyethylene, the surface photochlorination reduced gas permeation of carbon dioxide and oxygen down to 1/30 and 1/21 of the original polyethylene; it also improved the wettability without changing substantially other favorable physical properties such as tensile strength, elongation, and water vapor permeation. The water contact angle of chlorinated polyethylene was comparable to that of poly(vinyl chloride). The infrared spectra suggest the presence of the chlorine of the ? CHCl? CHCl? type rather than of the ? CCl₂? type in the photochlorination of polyethylene. In an effort to obtain useful membranes with a photocrosslinking functional group as a side chain, surface-photochlorinated polyethylene was allowed to react with sodium N,N-dimethyldithiocarbamate or sodium N-methyl-N-carboxymethyldithiocarbamate in dimethylformamide at 50°C for 48 hr according to the procedure by which poly(vinyl chloride) was previously reacted. The polymer thus obtained has 4.1 mole-% ? SCS? NMe₂ and 3.4 mole-% ? SCS? N(CH₃)CH₂COONa groups.     

A comparison of some rheological properties of concentrated solutions of chlorinated polyethylene and polyvinyl chloride in dioctyl phthalate

Steady-state and transient shear flow properties of poly(vinyl chloride) and chlorinated polyethylene dissolved in dioctyl phthalate were studied at different temperatures and polymer concentrations. In the case of poly(vinyl chloride)/dioctyl phthalate systems the presence of a sol–gel transition temperature was observed, whereas for chlorinated polyethylene/dioctyl phthalate systems the mechanism of flow was the same in the whole range of temperatures and concentrations. On the basis of the data obtained for both polymer/solution systems, we conclude that the presence of crystallites, rather than hydrogen bonds, determines the rheological behavior of poly(vinyl chloride)/dioctyl phthalate systems.     

Miscibility,morphology and tensile properties of vinyl chloride polymer and poly(ε‐caprolactone) blends

The miscibility, morphology and tensile properties of three blend systems of poly(ε‐caprolactone) (PCL) with poly(vinyl chloride) (PVC) and with two chlorinated PVCs (CPVCs) with different chlorine contents (63 wt% and 67 wt% of Cl) have been studied. Based on the shifts of single glass transition temperature, the Gordon–Taylor K parameter is calculated as a measurement of interaction strength between PCL and (C)PVCs. Higher K values are found for blends of (C)PVCs with higher chlorine content, together with the interaction χ parameters estimated from the melting point depression results. The morphology observed with polarized light microscopy shows that spherulites exist in blends rich in PCL (≥50 wt%) only. Wide angle X‐ray diffraction studies indicate that the crystal structure of PCL is independent of the Cl content of (C)PVCs. The tensile properties of various blends exhibit a minimum as the PCL content increases. The elongation at break increases with increasing PCL content. © 2000 Society of Chemical Industry     

Effects of core‐shell acrylate particles on impact properties of chlorinated polyethylene/polyvinyl chloride blends

The impact properties of core‐shell acrylate (CS‐ACR)/chlorinated polyethylene (CPE)/poly(vinyl chloride) (PVC) blends under different temperatures were investigated. The fracture surface morphologies of the blends were observed by scanning electron microscopy (SEM). The results show that there exists significant synergistic effect between CS‐ACR particles and CPE in toughening PVC, and the impact properties of the blends generally correlate well with SEM morphologies. Besides, with increasing CS‐ACR content, ductile–brittle transition point of the ternary blends remarkably shifts to a lower temperature. Dynamic mechanical analysis exhibited that intensity and area of low‐temperature tan δ peaks of the CPE/PVC blends increase obviously after the addition of CS‐ACR particles, which to some extent are just in line with the changes in impact strength and ductile–brittle transition point of the blends. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

苯乙烯氯化原位接枝改性氯化聚氯乙烯的研究

采用氯化原位接枝技术在聚氯乙烯（PVC）进行氯化反应的同时接枝上各种不同单体．从而制备改性的氯化聚氯乙烯（CPVC）。研究了PVC固相法氯化原位接枝St的规律，讨论了单体苯乙烯（St）加入量、氯含量对产物物理力学性能及流变性能的影响。结果表明：St的加入量为10份时，改性CPVC的屈服强度明显高于空白CPVC的屈服强度，但维卡软化点降低；改性CPVC的屈服强度和维卡软化点均随氟含量增加而增大；St的加入量适当，可以同时提高改性CPVC的屈服强度和冲击性能，降低熔体粘度。     

The preparation and analysis of chlorinated ethylene vinyl acetate copolymer as coating film in gas‐solid phase

In this article, the feasibility of preparing chlorinated ethylene vinyl acetate copolymer (CEVA) in gas–solid phase is investigated. Furthermore, the structure of the chlorination product and its performance as a coating material are also analyzed. Both the molecular structure and crystallinity of the product are well studied with various characterization methods, including ¹H‐NMR, Fourier transform infrared, gel permeation chromatography, differential scanning calorimeter, and so forth. The results show that the chlorination of EVA in gas–solid phase is feasible and the chlorine content of CEVA can be made over 60%. It is also found that when the chlorine content is low, chlorination can easily occur in ethylene section but rarely happens in vinyl acetate section. Nevertheless, when the chlorine content of CEVA rises over 35%, ? CH in the vinyl acetate section is also found chlorinated. The removal of hydrogen chloride is induced during chlorination, producing double bonds in the main chain. Besides, the trace of ? CCl₂ structure can also be found in the chain of CEVA. After chlorination, the crystallization will change and is negatively correlated with chlorine content. As the film forming material for coating, CEVA has its best performance with 50% chlorine content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41093.     

A study on poly(vinyl chloride) blends with chlorinated polyethylene and polyethylene

By means of a twin-roll masticator and Brabender rheometer, the effect of chlorinated polyethylene (CPE) and polyethylene (PE) on the impact strength and processability of poly(vinyl chloride) (PVC) was studied. The experimental results show that CPE can promote the plasticity of PVC and the effect increases with the amount of CPE. Addition of a small amount of PE in PVC/CPE (100/12) makes an impressive improvement in the impact strength of the mixture. The impact strength of PVC/CPE/PE (100/ 12/2.5) at 20°C is 30.0 kJ/m² higher than that of PVC/CPE (100/12). The dynamic viscoelastic spectra, tensile strength, and elongation test reveal that CPE is incompatible with PVC but may act as a compatibilizer for PVC/PE. The disperse state of the polyblend was studied by differential scanning calorimetry (DSC); it was found that the mixing sequence has an influence on the impact strength of the blend.     

Impact strength of high density microcellular poly(vinyl chloride) foams

The impact strength of microcellular poly(vinyl chloride) (PVC) produced from an industrial formulation was investigated. The solid‐state process with carbon dioxide as the blowing agent was used to prepare the specimens. Processing conditions were explored to produce microcellular PVC with a relative density of 0.6 and higher. These foams were impact tested by using a falling‐weight impact tester. Impact strength of microcellular PVC was found to decrease linearly with relative density. The gas saturation pressure did not significantly affect the impact strength of microcellular PVC foams. Microcellular PVC foams with up to 40% reduction in density possessed a normalized mean failure energy of 3.8 J/mm (0.85 in.‐lb/0.001 in.).     

Studies on mechanical and rheological properties of poly(vinyl chloride) modified with elastomers and rigid organic particles

Chlorinated polypropylene (CPP) as rigid organic particles and chlorinated polyethylene (CPE) as elastomer were used to modify the properties of poly(vinyl chloride) (PVC) by melt blending. Both mechanical and rheological properties of the PVC blends were investigated. The submicroscopic morphology of the blends was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results demonstrate that when the weight ratio of CPE to CPP is about 6 : 1, a sample with the best impact strength and without obvious decline in tensile strength can be obtained. The impact strength correlates well with SEM morphologies, and TEM micrographs in the necking of the tensile specimen indicate that a cold‐drawing deformation of rigid particles happens as reported by T. Kurauchi and T. Ohta (J Mater Sci 1984, 19, 1699). Therefore, a conclusion can be drawn that CPP particles acting similar to elastic particles can toughen PVC, and the cold‐drawing deformation is the primary reason for toughening the PVC blends. In addition, the addition of CPP can promote the processibility of PVC ternary blends. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2478–2483, 2003     

HDP—PVC／ABS合金材料的研究

研究了高聚合度聚氯乙烯（ＨＤＰ－ＰＶＣ）／ＡＢＳ二元体系力学性能以及添加第三组分对合金材料力学性能的影响。结果表明：ＨＤＰ－ＰＶＣ／ＡＢＳ配比为１００／２５时,共混物的综合性能好,体系能形成较完善的海岛结构;ＨＤＰ－ＰＶＣ／ＡＢＳ／ＭＢＳ体系中,ＭＢＳ能改善多元体系的界面性能,提高合金材料的综合性能;ＨＤＰ－ＰＶＣ／ＡＢＳ／ＣＰＥ体系中,ＣＰＥ能使形成网状结构和海岛结构共存的合金体系,提高合金材料     

核壳结构PMMA纳米微球增韧R-PVC/CPE

研究了核壳结构聚甲基丙烯酸甲酯（PMMA）纳米微球对硬质聚氯乙烯/氯化聚乙烯（R-PVC/CPE）体系的增韧和增强作用及其对加工流变性的影响。研究发现，核壳结构PMMA纳米微球与R-PVC/CPE基体在适当配比下共混，在显著提高基体的冲击强度的同时，拉伸强度、伸长率和加工流变性也有改善。