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Totally found 1604 items.

  • [期刊] OxyChem and Geon Form Joint Venture For Polyvinyl Chloride Resin Business
    ALEX TULLO; CHEMICAL MARKET REPORTER; V.253 N.26 1998; 1,32
  • [期刊] The Impact of Mounting Method on the Flammability Testing of Chlorinated Poly Vinyl Chloride (CPVC) Pipe Type Certification for Maritime Applications
    A series of tests was performed to elucidate the impact of the mounting methods on the performance of chlorinated poly vinyl chloride (CPVC) pipe in accordance with International Maritime Organization Fire Test Procedures Annex 1 Part 5. Also assessed, was the determination whether the current practice in type approval for the certification of all CPVC pipe sizes between smallest diameters, thinnest pipe tested and largest diameters, thickest pipe tested is a valid practice. Whole diameter pipe and pipe cut in half longitudinally were tested in the Lateral Ignition and Flame-Spread Test apparatus to determine if the different configurations of the pipe induced variability. A total of 42 tests were performed to look at sizes 12.7-mm copper tube size (CTS) through 38.1-mm Schedule 80 CPVC pipes. The following factors produced statistically different data at the 99% confidence limit: longitudinally half cut, versus whole, of the same pipe size and type, and thickness of the pipe for both total heat release and peak heat release rate (PHRR). Thickness is important with thicker pipe performing better in the testing. Whole pipe of the thinner material, CTS, versus the same pipe produced from longitudinally cut pipe, increased the heat produced significantly by holding the pipe in the combustion zone longer. Thin cut pipe appeared to melt and char, and fall out of the sample holder and the combustion zone, effectively reducing the mass consumed and energy produced. For Schedule 40 pipe of whole smaller pipe diameters, 12.7 mm, performed significantly better for both PHRR and total heat release than the longitudinally cut pipe. For diameters of 19.1 and 38.1-mm Schedule 40, the same trend was noted with the whole pipe performing significantly better. Thicker materials, such as Schedule 80, develop a thick char layer that stayed in place reducing combustion of CPVC.
  • [期刊] Structure and solubility of chlorinated poly(vinyl chloride) prepared by a gas-solid phase method
    Here, we modified the chlorination of a poly(vinyl chloride) (PVC) through a gas-solid phase method to prepare a highly soluble chlorinated PVC (CPVC). The structure of the CPVC was characterized by Fourier transform infrared spectroscopy, hydrogen-1 nuclear magnetic resonance, gel permeation chromatography, and energy dispersive X-ray spectroscopy, and the effects of molecular structure [gel content and vinylidene chloride (CCl2) molecular weight and distribution] on the solubility of CPVC were investigated. Results showed that molecular structures, such as CCl2, double bond, gel, molecular weight, and distribution had an effect on solubility, and the solubility of CPVC decreased with the increase in CCl2 content, number of double bonds, amount of gel, molecular weight, and distribution. The greater the degree of Inhomogeneous chlorination PVC particles or hydrochloride removal on the molecular chain is, the worse the solubility of CPVC is. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46880.
  • [期刊] Seismic Performance of Chlorinated Polyvinyl Chloride Sprinkler Pipes
    A major concern about chlorinated polyvinyl chloride (CPVC) pipes is the large swing of branch lines during earthquake-induced motions. National Fire Protection Association (NFPA) 13 defines spacing requirements for braces and restraints, based on pipe-bending strength, but does not limit the swing. Shake table tests and numerical simulations show that the swing of CPVC branch lines can be limited to an acceptable level if the ends are braced and the spacing of restraints follows the NFPA 13 requirements for CPVC, or if restraint spacing is reduced to about half of that currently allowed in NFPA 13.
  • [期刊] India imposes provisional ADD on CPVC imports from China, S Korea
    MUMBAI (ICIS)--India has imposed provisional anti-dumping duty (ADD) ranging between $2,031/tonne and $2,849/kg on chlorinated polyvinyl chloride compound and resin (CPVC) imports from China and South Korea, according to a statement from the Ministry of Finance.
  • [期刊] Physico-mechanical properties of NBR/CPVC blend vulcanizates and foams
    Foams were prepared from acrylonitrile-butadiene rubber (NBR)/chlorinated polyvinyl chloride (CPVC) blend compounds using a chemical blowing agent during compression molding. The effect of varying NBR/CPVC blend ratio and the time on the foams were investigated. The curing parameters showed that both the maximum torque and the difference between the maximum and minimum torque decreased with increase of CPVC content. The limiting oxygen index (LOI) of the blend vulcanizate increased with increase of CPVC content, reached up to 30% for the NBR/CPVC blend with blend ratio 50/50. The SEM micrographs of the NBR/CPVC blend indicate semi-compatibility between the blend phases. The NBR/CPVC foams prepared using a chemical blowing agent, showed closed cell structures, which were uniformly distributed across the blend phases. The average cell sizes increased and foam density decreased with increase of CPVC content. Tensile strength and tear strength of both vulcanizates and foams increased with increase CPVC content. Hardness of the foams increased but resilience of the foams decreased with increase of CPVC content. Density, tensile strength, tear strength, and hardness of the foams increased but resilience decreased when the compression molding time of the foam was increased. J. VINYL ADDIT. TECHNOL., 25:182-188, 2019. (c) 2018 Society of Plastics Engineers
  • [期刊] Structure and adsorptive property of carbon materials derived from thermal and mechanochemical reaction of CaC2 and chlorinated polymers
    In this study, calcium carbide-derived carbon materials (CMs) were prepared by reacting CaC2 with chlorinated polymers via mechanochemical (CMs-M) and thermochemical (CMs-T) reaction in a planetary ball mill and tubular reactor, respectively. Their composition, structure, and adsorptive properties for dibenzothiophene (DBT) in oil and Hg2+ in water were studied, and the reaction mechanism was analyzed. In comparison with CMs-T, CMs-M possess higher specific area (600 +/- 30 m(2).g(-1)) and rich acetylenic and O-containing functional groups, and accordingly higher adsorptivity. Its saturated adsorbance is as high as 291.2 mg-Hg2+.g(-1), and the adsorption isotherm can be well represented by Langmuir model, which manifests the chemisorption arising from the unique interaction between Hg2+ and the functional groups. CMs-M is one of the best carbonaceous sorbents for Hg2+ removal considering its high adsorption rate and capacity, high partition coefficient (21.8 mg.g(-1).mu M-1 at equilibrium concentration of 0.18 ppm), high selectivity w.r.t other heavy metal ions, and excellent recyclability. The mechanochemical method is more suitable for massive production of CMs in view of its mild operation condition and controllable reaction process. This study also sheds a light on the resource utilization of abundant highly chlorinated polymers, like polyvinylchloride (PVC) and chlorinated PVC (CPVC), for the manufacture of CMs-M.
  • [期刊] CPVC/PVC与CPVC/ABS合金加工性能研究
    研究了聚氯乙烯(PVC)与丙烯腈-丁二烯-苯乙烯共聚物(ABS)用量对氯化聚氯乙烯(CPVC)/PVC、CPVC/ABS合金最低塑化温度Tmin、塑化时间t、平衡扭矩TQ等加工性能以及体系的热稳定性的影响;同时对合金的耐热性能进行了分析。结果表明,随着体系中PVC、ABS用量的增加,CPVC/PVC、CPVC/ABS合金的Tmin、t和TQ降低,而体系的热稳定性增加。
  • [期刊] CPVC/PVC与CPVC/ABS合金加工性能研究
    研究了聚氯乙烯(PVC)与丙烯腈-丁二烯-苯乙烯共聚物(ABS)用量对氯化聚氯乙烯(CPVC)/PVC、CPVC/ABS合金最低塑化温度Tmin、塑化时间t、平衡扭矩TQ等加工性能以及体系的热稳定性的影响;同时对合金的耐热性能进行了分析。结果表明,随着体系中PVC、ABS用量的增加,CPVC/PVC、CPVC/ABS合金的Tmin、t和TQ降低,而体系的热稳定性增加。
  • [期刊] CPVC埋地管、CPVC热水管、 PE-RT耐热聚烯管
    进入21世纪以来,由于排水,给水、燃气、光纤通讯、埋地电力管等五大领域的需求,造成中国塑料管材历史性大发展的机遇.中国塑料管材加工业的进步,尤其是科技的进步,是面对挑战,实现机遇的主要途径是努力学习把国际上最优秀的管材引进到中国来.
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