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Synthetic Features and Mechanism for the Preparation of vinyl chloride-co-Butyl Acrylate-co-vinyl Acetate Terpolymer via Precipitation Polymerization

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Chinese Journal of Polymer Science 2023年第11期41卷 1714-1724,I0006页

作者： Chang-Tong Song Xian-Hong Zhang Dong Chen Yu-Hong Ma Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Without any type of su rfactant or dispersing agent,precipitation polymerization has great superiorities in both polymer synthesis and *** the present work,the polymerization of vinyl chloride(VC),n-butyl acrylate(BA),and vinyl acetate(VAc)are conducted in the precipitation polymerization system and series of their random terpolymers poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate)(PCBV)are synthesized *** effects of various polymerization conditions,including solvent polarity,temperature,initiator concentration,and monomer feed ratios on the polymerization kinetics,number-average molecular weight(M_(n)),and terpolymer composition are investigated *** solvent and the monomer feed ratio are crucial factors not only for the polymer morphology,but also for the reaction *** the non-polar solvent such as n-hexane,the PCBV displays particle morphology when the composition of BA ratio lower than 10 wt%.Otherwise,the PCBV forms a uniform polymer phase and precipitates out from the *** the polar solvent,e.g.,dimethyl carbonate(DMC)and ethanol,the PCBV polymer maintains a slurry state either in low or in high monomer feed ***,VC based ternary copolymer that obtained in n-hexane has much lower M_(n)(40 wt%)compared with emulsion and suspension ***,the terpolymer can be easily sepa rated by simple centrifugation.

关键词： Precipitation polymerization Copolymerization vinyl chloride Low molecular weight

Understanding the role of tungsten on Pt/CeO_(2)for vinyl chloride catalytic combustion

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Journal of Rare Earths 2022年第9期40卷 1462-1470,I0005页

作者： Qifeng Zhang Zhengbo Zhou Tian Fang Han Gu Yanglong Guo Wangcheng Zhan Yun Guo Li Wang Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis School of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Spherical CeO_(2)synthesized by the hydrothermal process was used as support to prepare Pt/WO_(3)/CeO_(2),and the effects of tungsten(W)contents on activity,stability and polychlorinated by-products were investigated to understand the role of W for vinyl chloride(VC)catalytic *** introduction of12 wt%W to Pt/CeO_(2)(P12 WC)exhibits the highest catalytic activity with 90%conversion of VC at 250℃,meanwhile the stability improves and the polychlorinated by-products in the tail gas significantly decrease due to the removal of dissociated Cl species in the formation of *** beneficial effects of W on Pt/CeO_(2)are closely related to the chemical state of Pt,redox and surface acid sites *** doped W not only makes Pt disperse evenly on the support with the high valence,but also weakens the interaction between Pt and CeO_(2)by the formation of Pt-O-W and Pt-O-W-O-Ce species,which facilitates oxygen *** addition,the modification of W species also significantly increases the surface acidity amount and changes the distribution of acid sites.

关键词： Tungsten oxides vinyl chloride Catalytic oxidation Pt/CeO_(2) By-products Rare earths

Catalytic combustion of vinyl chloride emissions over Co_(3)O_(4) catalysts with different crystallite sizes

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Rare Metals 2021年第4期40卷 817-827页

作者： Wen-Chao Hua Ming-Qi Li Yang-Long Guo Guang-Tao Chai Hao Liu Yun Guo Li Wang Wang-Cheng Zhan Key Laboratory for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of Co_(3) O_(4) catalysts was prepared by ammonia(Co-AP) and oxalate(Co-OP) precipitation,solgel(Co-SG),and urea hydrothermal(Co-UH) methods,and their physicochemical properties were characterised by numerous techniques including X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen sorption,X-ray photoelectron spectroscopy(XPS),temperature-programmed reduction of H_(2)(H_(2)-TPR),temperature-programmed desorption of O_(2)(O_(2)-TPD),and temperature-programmed desorption of NH_(3)(NH_(3)-TPD).The catalytic activity of each catalyst was estimated for the catalytic combustion of vinyl chloride(VC) *** crystallite size of the Co_(3) O_(4) catalyst was found to be well correlated with the amounts of surface-adsorbed oxygen species and number of acid sites on the catalyst surface,and consequently,determined several physicochemical properties of the *** the catalysts studied here,the Co-AP catalyst exhibits the smallest crystallite size,which increases the specific surface area and the concentration of Co^(2+) on the catalyst ***,in turn,enhances the redox property,oxygen mobility,and the number of acid sites associated with the Co-AP *** fact,the Co-AP catalyst exhibits the best catalytic activity for VC combustion at 360℃and does not produce any chlorinated by-products.

关键词： Catalytic combustion vinyl chloride Cobalt oxides Crystallite size Preparation methods

PARTICLE MORPHOLOGY OF POLY(vinyl chloride)RESIN PREPARED BY SUSPENDED EMULSION POLYMERIZATION

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Chinese Journal of Polymer Science 2003年第4期21卷 447-452页

作者：包永忠 State Key Laboratory of Polymer Engineering Zhejiang University Hangzhou 310027 China

Suspended emulsion polymerization was used to prepare poly(vinyl chloride) (PVC) resin. Fine PVC particleswere formed at low polymerization conversions. The amount of fine panicles decreases as conversion increases anddisappears at conversions greater than 30%. Scanning electron micrographs show that PVC grains are composed of looselycoalesced primary particles, especially for PVC resins prepared in the presence of poly(vinyl alcohol) dispersant. The size ofprimary particles increases and porosity decreases with the increase of conversion. In view of the particle features of PVCresin, a particle formation mechanism including the formation of primary particles and grains is proposed. The formationprocess of primary particles includes the formation of particle nuclei, coalescence of particle nuclei to form primary particles,and growth of primary particles. PVC grains are formed by the coagulation of primary particles. The loose coalescence ofprimary particles is caused by the colloidal stability of primary particles and the low swelling degree of vinyl chloride in the primary particles.

关键词： Suspended emulsion polymerization vinyl chloride Particle size distribution Morphology Particle formation mechanism

DFT study on the selective oxidation of vinyl chloride on different metal surfaces

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Journal of Natural Gas Chemistry 2011年第2期20卷 173-178页

作者： Ruipeng Ren Ruixin Xi Xianyong Pang Yongkang Lu College of Chemistry and Chemical Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 Shanxi China

Selective epoxidation of vinyl chloride on Ag（111）, Pt（111） and Rh（111） with pre-adsorbed atomic oxygen has been studied by density functional theory （DFT） calculation with the periodic slab model. The reaction energies and activation energies of the epoxidation reaction are determined. Because of the asymmetry of vinyl chloride, three competitive reaction pathways are investigated. The results indicate that the most possible reaction pathway is pathway III. Compared the activation energies of the epoxidation reaction on Ag（111）, Pt（111） and Rh（111）, it is obvious that the reaction via OMMC（3） on Ag（111） is the most possible process. However, the selectivity to the target product over Ag（111） is the lowest among the three metals. The results also indicate that the formation of chloroacetaldehyde is more favorable than that of chloroepoxide.

关键词： vinyl chloride DFT selectivity epoxidation

Nitrogen doped carbon catalyzing acetylene conversion to vinyl chloride

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Journal of Energy Chemistry 2014年第2期23卷 131-135页

作者： Xingyun Li Xiulian Pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences

Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vital to explore alternative catalysts without mercury. We report here that N-doped carbon can catalyze directly transformation of acetylene to vinyl chloride. Particularly, N-doped high surface area mesoporous carbon exhibits a rather high activity with the acetylene conversion reaching 77% and vinyl chloride selectivity above 98% at a space velocity of 1.0 ***-l.g-1 and 200 ~C. It delivers a stable performa℃nce within a test period of 100h and no obvious deactivation is observed, demonstrating potentials to substitute the notoriously toxic mercuric chloride catalyst.

关键词： acetylene hydrochlorination vinyl chloride mercury-free N doped carbon

An Ecological Evaluation of vinyl chloride Exposure and Liver Cancer Incidence and Mortality in Texas

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Journal of Clinical and Translational Hepatology 2021年第1期9卷 99-105页

作者： Kevin M.Towle Stacey M.Benson Natalie S.Egnot Gary M.Marsh Cardno ChemRisk San FranciscoCAUSA Cardno ChemRisk PittsburghPAUSA

The goal of this analysis was to evaluate the association between county-level ambient vinyl chloride(VC)and county-level liver cancer incidence and mortality rates in *** county-level ambient VC data were obtained from the National Air Toxics ***-adjusted county-level liver cancer incidence rates were abstracted from the Texas Cancer Registry and age-standardized county-level liver cancer mortality rates were obtained from the peer-reviewed *** imputation was utilized to impute incidence rates in counties with suppressed liver cancer incidence *** binomial and Poisson regression models were utilized to evaluate the association between county-level ambient VC and county-level liver cancer incidence and mortality rates,respectively,adjusted for county-level heavy drinking prevalence,hepatitis mortality rates,median income,and race(percent Hispanic).County-level ambient VC was not associated with county-level liver cancer incidence or mortality ***,when compared to the lowest tertile of ambient VC,the middle(relative risk[RR]:1.06,95%confidence interval[CI]:0.95-1.19)and highest(RR:1.03,95%CI:0.90-1.17)tertiles of ambient VC were not associated with liver cancer ***,county-level ambient VC in the middle(RR:0.95,95%CI:0.85-1.05)and highest(RR:0.93,95%CI:0.82-1.05)tertiles were not associated with liver cancer *** analysis suggests that county-level ambient VC is not associated with liver cancer incidence or mortality in *** study provides novel results regarding liver cancer risk from low-level non-occupational exposure to ambient VC.

关键词： vinyl chloride Liver cancer Epidemiology Incidence

Insight of chemical environmental risk and its management from the vinyl chloride accident

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 167-171页

作者： Bin Wang Liping Heng Qian Sui Zheng Peng Xuezhi Xiao Minghui Zheng Jianxin Hu Heidelore Fiedler DamiàBarceló Gang Yu Beijing Laboratory of Environmental Frontier Technology Beijing Key Laboratory of Emerging Organic Contaminants ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhou 215163China School of Chemistry Beihang UniversityBeijing 100191China School of Resources and Environmental Engineering East China University of Science and TechnologyShanghai 200237China Foreign Environmental Cooperation Center Ministry of Ecology and Environment of ChinaBeijing 100035China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China School of Science and Technology MTM Research CentreÖrebro UniversitySE-70182ÖrebroSweden Department of Environmental Chemistry Institute of Environmental Assessment and Water ResearchSpanish Council for Scientific Research(CSIC)Barcelona 08034Spain Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

The combustion of vinyl chloride(VC)after the train derailment accident in Ohio,USA in February,2023 has caused widespread concern around the *** paper tried to analyze several issues concerning the accident,including the appropriateness of the VC combustion in the emergency response in this accident,the meanings of so-called“controlled combustion”,the potential environmental risks caused by VC and combustion by-products,and follow-up *** our view,this accident had surely caused environmental and health risks to some ***,a comprehensive environmental risk assessment is necessary,and then the site with risk should be comprehensively remediated,hazardous waste should be harmlessly treated as soon as ***,this accident suggests that further efforts should be taken to bridge the gap between chemical safety management and their environmental risk management.

关键词： vinyl chloride Combustion Chemical safety management Environmental risk Emerging contaminants

Analyzing Precipitation Acidity Changes Post Train Derailment and vinyl chloride Release in East Palestine, Ohio: Exploring Biomedical and Environmental Ramifications

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Journal of Water Resource and Protection 2023年第9期15卷 442-480页

作者： Godspower O. Sebe Kristen Vogle Brendan Meyers Adenike Elizabeth Adewoyin Livina C. Iheme Henrietta Nneka Emeka Department of Chemistry Chemical and Biomedical Engineering University of New Haven West Haven USA Department of Chemistry Southern Connecticut State University New Haven USA Department of Chemistry & Biochemistry University of Toledo Toledo OH USA Department of Data & Buiness Analytics University of New Haven West Haven USA

This study investigates the aftermath of a significant train derailment and vinyl chloride release incident in East Palestine, Ohio, with a particular focus on the analysis of precipitation acidity changes and the concentration of vinyl chloride in samples. The research seeks to elucidate the complex relationship between industrial accidents, atmospheric chemistry, and their potential implications for human health and the environment. Through meticulous examination of variations in precipitation acidity patterns, this study provides valuable insights into the dispersion and impact of toxic agents in the environment following industrial mishaps. The results underscore the intricate interplay between these factors, highlighting the need for a multidisciplinary approach that bridges the realms of environmental science and biomedical concerns. This research contributes to a growing body of knowledge that addresses the broader consequences of industrial incidents on public health. It underscores the importance of proactive measures, such as enhanced monitoring and surveillance, risk assessment, public education, and regulatory reform, to mitigate the environmental and health risks associated with industrial activities involving hazardous materials. By fostering collaboration between experts and stakeholders, this study advocates for a holistic approach to safeguarding both our environment and the well-being of communities affected by industrial accidents.

关键词： pH Precipitation East Palestine ANOVA Environment vinyl chloride Health