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The synthesis and spectroscopic investigation of vinylated meso-tetraphenylporphyrin 被引量:1
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作者 Jin Qiang Xue Ya Qing Feng Lei Wang Ling Hui Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1319-1322,共4页
A series of new vinylated 5,10,15,20-tetraphenylporphyrins have been synthesized and characterized by ^1H NMR, MS, UV-vis and fluorescence studies. Following selective excitation of the porphyrin compounds with UV lig... A series of new vinylated 5,10,15,20-tetraphenylporphyrins have been synthesized and characterized by ^1H NMR, MS, UV-vis and fluorescence studies. Following selective excitation of the porphyrin compounds with UV light, the energy is transferred to the porphyrin core and reemitted as red light. In Comparison to tetraphenylporphyrin (TPP), the luminescence properties are markedly improved. 展开更多
关键词 PORPHYRIN SPECTRUM vinylated LUMINESCENCE
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固体磷酸催化竹屑液化的反应机理
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作者 吴斌 何异莞 +1 位作者 唐宏伟 房桂干 《四川林业科技》 2024年第5期42-48,共7页
固体磷酸为催化剂液化竹屑制备生物基多元醇,利用FT-IR、GC-MS、NMR等技术和方法对液化产物组成进行了表征,研究其反应机理。研究结果表明:Vinyl ethyl carbitol等烯烃类的生成主要是通过固体磷酸催化PEG400一端脱去羟基形成的,而戊二... 固体磷酸为催化剂液化竹屑制备生物基多元醇,利用FT-IR、GC-MS、NMR等技术和方法对液化产物组成进行了表征,研究其反应机理。研究结果表明:Vinyl ethyl carbitol等烯烃类的生成主要是通过固体磷酸催化PEG400一端脱去羟基形成的,而戊二酸物质等物质主要是由固体磷酸催化纤维素等生物质通过氧化重排而形成,除此之外,固体磷酸还解决液化产物酸值高的问题。 展开更多
关键词 固体磷酸 催化剂 生物基多元醇 Vinyl ethyl carbitol 戊二酸 酸值
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Innovative approach to boosting the chemical stability of AZ31 magnesium alloy using polymer-modified hybrid metal oxides
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作者 Mosab Kaseem Ananda Repycha Safira +3 位作者 Mohammad Aadil Tehseen Zehra Muhammad Ali Khan Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1068-1081,共14页
Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties.However,the integration of polymeric frameworks with MgO/WO_(3) composite l... Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties.However,the integration of polymeric frameworks with MgO/WO_(3) composite layers faces challenges due to the lack of understanding of the formation mechanism and the challenge of determining the impact of self-assembled architecture on anticorrosive properties.In this study,we aimed to enhance the corrosion resistance of the MgO layer produced by plasma electrolysis(PE)of AZ31 Mg alloy by incorporating WO_(3) with partially phosphorated poly(vinyl alcohol)(PPVA).Two types of porous MgO layers were produced using the PE process with an alkaline-phosphate electrolyte,one with and one without WO_(3) nanoparticles,which were subsequently immersed in an aqueous solution of PPVA.Incorporating PPVA into the WO_(3)-MgO layer resulted in hybrids being deposited in a fragmented manner,creating a“laminar reef-like structure”that sealed most of the structural defects in the layer.The PPVA-sealed WO_(3)-based coating exhibited superior corrosion resistance compared to the other samples.Computational analyses were employed to explore the mechanism underlying the formation of PPVA/WO_(3) hybrids on the MgO layer.These findings suggest that PPVA-WO_(3)-MgO hybrid coatings can potentially improve corrosion resistance in various fields. 展开更多
关键词 Plasma electrolysis Poly(vinyl alcohol) Tungsten trioxide SEALING CORROSION DFT.
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A comparative study for petroleum removal capacities of the bacterial consortia entrapped in sodium alginate,sodium alginate/poly(vinyl alcohol),and bushnell haas agar
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作者 Sezen Bilen Ozyurek 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期705-715,共11页
The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different pol... The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different polymers such as Sodium Alginate(SA),Sodium Alginate/Poly(Vinyl Alcohol)(SA/PVA),and Bushnell Haas Agar(BHA).In addition to SA and SA/PVA,which are cost-effective,non-toxic and have different functional groups,BHA,which is frequently encountered in laboratory-scale studies but has not been used as an entrapment material until now.Based on these,the polymers with different surface morphologies and chemical compositions were analyzed by SEM and FT-IR.While the petroleum removal efficiency was higher with the entrapped bacterial consortia than with the free one,BHA-entrapped bacterial consortium enhanced the petroleum removal more than SA and SA/PVA.Accordingly,the degradation rate of bacterial consortia entrapped with BHA was 2.039 day^(-1),SA/PVA was 1.560,SA was 0.993,the half-life period of BHA-entrapped bacterial consortia is quite low(t_(1/2)=0.339)compared with SA(t_(1/2)=0.444)and SA/PVA(t_(1/2)=0.697).The effects of the four main factors such as:amount of BHA(0.5,1,1.5,2,2.5,3 g),disc size(4,5,6,7,8 mm),inoculum concentration(1,2.5,5,7.5,10 mL),and incubation period on petroleum removal were also investigated.The maximum petroleum removal(94.5%)was obtained at≥2.5 mL of bacterial consortium entrapped in 2 g BHA with a 7 mm disc size at 168 h and the results were also confirmed by statistical analysis.Although a decrease was observed during the reuse of bacterial consortium entrapped in BHA,the petroleum removal was still above 50%at 10th cycle.Based on GC-MS analysis,the removal capacity of BHA-entrapped consortium was over 90%for short-chain n-alkanes and 80%for medium-chain n-alkanes.Overall,the obtained data are expected to provide a potential guideline in cleaning up the large-scale oil pollution in the future.Since there has been no similar study investigating petroleum removal with the bacterial consortia entrapped with BHA,this novel entrapment material can potentially be used in the treatment of petroleum pollution in advanced remediation studies. 展开更多
关键词 Entrapment of bacterial consortia PETROLEUM RemovalBushnell Haas agar Sodium alginate Sodium alginate/poly(vinyl alcohol)
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Polyurethane Hybrid-Based Wood Adhesive: Review
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作者 Rahul Khandagale Sainath Gadhave Ravindra V. Gadhave 《Open Journal of Polymer Chemistry》 2024年第1期41-62,共22页
Based on commercially available polyvinyl alcohol (PVA) stabilised polyvinyl acetate (PVAc), emulsion adhesives are neither heat nor moisture-resistant and show weak strength at high relative humidity and high tempera... Based on commercially available polyvinyl alcohol (PVA) stabilised polyvinyl acetate (PVAc), emulsion adhesives are neither heat nor moisture-resistant and show weak strength at high relative humidity and high temperatures. Pre- or post-crosslinking is another method used to manufacture a conventional vinyl-based homopolymers or copolymers system with improved water resistance. Vinyl neodecanoate (VeoVa), N-methylolacrylamide (NMA), Methacrylamide, methacrylic acid (MAA), and other self-crosslinking comonomers are typically inserted to produce highly water-resistant vinyl based homopolymers or copolymers. Additionally, organic crosslinkers like glyoxal, glutaraldehyde, citric acid, tartaric acid, and the like, as well as inorganic crosslinkers like acidic metal salts like aluminium chloride, aluminium nitrate, boric acid, and the like, can be used to prepare the highly water-resistant vinyl based homopolymers or copolymers. It is also possible to combine the self-crosslinking comonomers with the organic crosslinkers. Recently, a different hybrid chemistry has been developed that improves lap shear strength, has outstanding water resistance, good durability, and doesn’t require any additional crosslinker agents. Two distinct polymers were combined to develop hybrid polymers. They usually involve mixing an organic polymer with a polymer. There are many capping agents that are used for polyurethanes to produce acrylics that are capped with polyurethane and used as an oligomer in PVAc wood glue. Here, in this paper, we reviewed the different hybrid chemistry based on polyurethane chemistry for wood bonding applications. 展开更多
关键词 Vinyl Acetate HYBRID POLYURETHANE WOOD ADHESIVE
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Direct synthesis of nitrogen-doped mesoporous carbons for acetylene hydrochlorination 被引量:7
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作者 杨勇 蓝国钧 +1 位作者 王小龙 李瑛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1242-1248,共7页
Nitrogen‐doped ordered mesoporous carbon (N‐OMC) catalysts were directly synthesized using SBA‐15 as a hard template and sucrose as a carbon source. Urea, which was used as the nitrogen source, was carbonized wit... Nitrogen‐doped ordered mesoporous carbon (N‐OMC) catalysts were directly synthesized using SBA‐15 as a hard template and sucrose as a carbon source. Urea, which was used as the nitrogen source, was carbonized with sucrose. A 3.6 wt% nitrogen doping of the carbon framework was achieved, with more than 70%of the nitrogen incorporated as quaternary nitrogen species. Only 0.2 wt% nitrogen doping, with only 32.7% quaternary nitrogen incorporation was obtained in an N‐OMC catalyst (N‐OMC‐T) prepared using a two‐step post‐synthesis method. The acetylene hy‐drochlorination activities of N‐OMC catalysts prepared via the one‐step method were higher than that of the N‐OMC‐T catalyst because of the higher nitrogen loadings. 展开更多
关键词 ACETYLENE HYDROCHLORINATION Vinyl chloride MERCURY-FREE N-doped carbon
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Effect of Calcination Temperature on La-Modified Al2O3 Catalysts for Vapor Phase Hydrofluorination of Acetylene to Vinyl Fluoride 被引量:4
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作者 毕庆员 鲁继青 +2 位作者 邢丽琼 郭明 罗孟飞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期89-94,I0002,共7页
A La-modified Al2O3 catalyst was prepared with deposition-precipitation method. The effect of calcination temperature on the reactivity for vapor phase hydrofluorination of acetylene to vinyl fluoride. The catalysts c... A La-modified Al2O3 catalyst was prepared with deposition-precipitation method. The effect of calcination temperature on the reactivity for vapor phase hydrofluorination of acetylene to vinyl fluoride. The catalysts calcined at different temperatures were characterized using NH3-TPD, pyridine-FTIR, X-ray diffraction, and Raman techniques. It was found that the calcination process could not only change the structure of these catalysts but also modify the amount of surface acidity on the catalysts. The catalyst calcined at 400 ℃ exhibited the highest conversion of acetylene (94.6%) and highest selectivity to vinyl fluoride (83.4%) and lower coke deposition selectivity (0.72%). The highest activity was related to the largest amount of surface acidity on the catalyst, and the coke deposition was also related to the total amount of surface acidic sites. 展开更多
关键词 La2O3-Al2O3 catalyst Hydrofluorination reaction Vinyl fluoride ACETYLENE Calcination temperature
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原位微悬浮法纳米二氧化硅/氯醚树脂复合粒子的制备及表征 被引量:4
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作者 杨建军 吕国斌 +3 位作者 吴庆云 张建安 吴明元 王申生 《合成橡胶工业》 CAS CSCD 北大核心 2014年第2期91-95,共5页
用硅烷偶联剂KH-570对纳米SiO2进行表面处理,干燥后预先分散于乙烯基异丁基醚中,再通过原位微悬浮聚合法制备了纳米SiO2/氯醚树脂复合粒子;考察了KH-570添加量、pH值和反应时间对纳米SiO2表面接枝率的影响,并用傅里叶变换红外光谱、核... 用硅烷偶联剂KH-570对纳米SiO2进行表面处理,干燥后预先分散于乙烯基异丁基醚中,再通过原位微悬浮聚合法制备了纳米SiO2/氯醚树脂复合粒子;考察了KH-570添加量、pH值和反应时间对纳米SiO2表面接枝率的影响,并用傅里叶变换红外光谱、核磁共振氢谱、差示扫描量热分析、热重分析和透射电子显微镜对纳米SiO2和纳米SiO2/氯醚树脂复合粒子进行了表征.结果表明,纳米SiO2表面改性的最佳条件为:KH-570与纳米SiO2质量比为1.2∶1,pH值为8.0 ~9.0,反应时间为8h;制备出的纳米SiO2/氯醚树脂复合粒子以纳米SiO2为核,其平均粒径为150~ 250 nm,其中核的直径为100~150 nm. 展开更多
关键词 纳米二氧化硅 氯醚树脂 原位微悬浮聚合法 表面改性 核壳结构 接枝率 poly (vinyl chloride-co-vinyl ISOBUTYL ether)
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辐照改性聚乙烯醇缩甲醛精密过滤材料的制备与性能分析 被引量:3
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作者 王连才 曹巍 +3 位作者 翟彤 翟宇 酒永斌 曾心苗 《核技术》 CAS CSCD 北大核心 2014年第6期45-48,共4页
聚乙烯醇缩甲醛过滤材料具有气孔细微、过滤精度高、通量大、无纤维脱落等特点,在精密过滤领域具有广阔的应用空间。本研究以聚乙烯醇PVA-1799和甲醛为主要原料,季戊四醇三丙烯酸酯为改性剂,利用γ射线辐照技术制备了改性聚乙烯醇缩甲醛... 聚乙烯醇缩甲醛过滤材料具有气孔细微、过滤精度高、通量大、无纤维脱落等特点,在精密过滤领域具有广阔的应用空间。本研究以聚乙烯醇PVA-1799和甲醛为主要原料,季戊四醇三丙烯酸酯为改性剂,利用γ射线辐照技术制备了改性聚乙烯醇缩甲醛(Poly(vinyl formal),PVF)过滤材料,对材料的泡孔结构、力学性能、尺寸稳定性、吸水率、耐水性能及耐油性能进行了测试与表征。结果表明,材料的孔径小于300μm,拉伸断裂强度达到3.01 MPa,撕裂强度达到13.23 MPa;以辐射技术所制备的泡沫材料尺寸稳定性良好,具有更佳的力学性能和耐油耐水性能。采用辐照技术能够简化PVF过滤材料生产工艺,减少无机酸和甲醛用量,减轻环境污染。 展开更多
关键词 辐照改性 聚乙烯醇缩甲醛(Poly(vinyl formal) PVF) 精密过滤
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聚乙烯醇纳米纤维的制备与静电纺丝工艺研究 被引量:10
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作者 杜江 李罡 蓝彩娟 《中外医学研究》 2014年第8期149-151,共3页
近年来,利用高压静电纺丝技术开发生物医用材料制品已成为研究的热点。本实验利用高压电纺丝技术制备了聚乙烯醇(PVA)纳米纤维,研究了PVA溶液静电纺丝过程中PVA浓度,纺丝电压和收集板距离等电纺工艺参数对PVA纤维形成及其微观形貌的影... 近年来,利用高压静电纺丝技术开发生物医用材料制品已成为研究的热点。本实验利用高压电纺丝技术制备了聚乙烯醇(PVA)纳米纤维,研究了PVA溶液静电纺丝过程中PVA浓度,纺丝电压和收集板距离等电纺工艺参数对PVA纤维形成及其微观形貌的影响。实验结果表明,PVA纤维直径随着电纺溶液浓度的增加而增加;当电压从15 kV增加至25 kV时,纤维直径逐渐下降;电压从25 kV增加至30 kV时纤维直径反而开始增加;收集板间距离增加纤维直径也相对的减小。PVA纤维在浓度20%,电压25 kV,收集板距离15 cm,流速0.2 ml/h的工艺条件下形貌和直径最佳,静电纺丝过程也最稳定。 展开更多
关键词 聚乙烯醇 高压静电纺丝 Poly(vinyl alcohol)
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Removal of manganese from waste water by complexation-ultrafiltration using copolymer of maleic acid and acrylic acid 被引量:2
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作者 邱运仁 毛廉君 王伟华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1196-1201,共6页
Copolymer of maleic acid and acrylic acid (PMA-100), combining with polyvinyl butyral (PVB) ultrafiltration membrane was used for the removal of Mn(II) from waste water by complexation-ultrafiltration. The carbo... Copolymer of maleic acid and acrylic acid (PMA-100), combining with polyvinyl butyral (PVB) ultrafiltration membrane was used for the removal of Mn(II) from waste water by complexation-ultrafiltration. The carboxylic group content of PMA-100 and the rate of complexation reaction were measured. Effects of the mass ratio of PMA-100 to Mn(II) (n), pH, background electrolyte, etc on the rejection rate (R) and permeate flux (J) were investigated. The results show that carboxylic group content of PMA-100 is 9.5 mmol/g. The complexation of Mn(II) with PMA-100 is rapid and completed within 5 min at pH 6.0. Both R and J increase with pH increasing in the range of 2.5-7.0, and R increases with the increase of n at pH 6.0 while J is little affected. The background electrolyte leads to the decrease of R, and CaCl2 has much greater effect on R than NaCl at the same ionic strength. 展开更多
关键词 complexation-ultrafitration copolymer of maleic acid and acrylic acid poly (vinyl butyral) hollow fiber membrane MANGANESE wastewater treatment
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Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen
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作者 马洪波 许仙菊 +3 位作者 宁运旺 汪吉东 张辉 张永春 《Agricultural Science & Technology》 CAS 2014年第3期412-416,421,共6页
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat... [Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited. 展开更多
关键词 Water immersion method Pot experiment method Vinyl chloride-vinyl acetate copolymer Nutrient release characteristics Soil mineral nitrogen
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PBT替代钢材提高塑料窗框保温性
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作者 唐伟家 《现代塑料加工应用》 CAS 北大核心 2008年第5期7-7,共1页
据“Modern Plastics Worldwide,2008,85(85):28”报道,2008年4月在德国Nuremberg举办的世界最大的门和窗框展览会上,德国窗框生产厂和型材加工厂Alupast公司推出新的窗框系统Vinyl Ideal 4000,优点为保温性好,性价比高。
关键词 保温性 窗框 PBT 塑料 钢材 VINYL ast公司 IDEAL
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聚氯乙烯/邻苯二甲酸二烯丙酯聚合物加工性能和力学性能研究 被引量:3
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作者 陈继华 王伟 皮红 《中国塑料》 CAS CSCD 北大核心 2017年第3期15-18,共4页
采用转矩流变仪对实验室自制的聚氯乙烯/邻苯二甲酸二烯丙酯(PVC/DAP)聚合物的加工性能进行了研究,探讨了DAP含量对PVC加工性能的影响。结果表明,随着DAP含量的增加,PVC/DAP聚合物的塑化时间缩短,平衡扭矩、峰值扭矩均减小,平衡温度下降... 采用转矩流变仪对实验室自制的聚氯乙烯/邻苯二甲酸二烯丙酯(PVC/DAP)聚合物的加工性能进行了研究,探讨了DAP含量对PVC加工性能的影响。结果表明,随着DAP含量的增加,PVC/DAP聚合物的塑化时间缩短,平衡扭矩、峰值扭矩均减小,平衡温度下降;拉伸强度和断裂伸长率均有所增加。 展开更多
关键词 聚氯乙烯 邻苯二甲酸二烯丙酯 加工性能 力学性能 poly(vinyl chloride)
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抗静电剂对软质聚氯乙烯电学性能的影响 被引量:3
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作者 张浙冰 郑玉婴 《中国塑料》 CAS CSCD 北大核心 2017年第3期28-34,共7页
在聚氯乙烯(PVC)/邻苯二甲酸二辛酯(DOP)中加入抗静电剂SAS93、抗静电剂SN、导电炭黑、乙炔炭黑等助剂,采用熔融共混法制备了抗静电软质PVC片材;采用万能试验机、高绝缘电阻测量仪、场发射扫描电子显微镜研究了抗静电剂种类和组分对PVC... 在聚氯乙烯(PVC)/邻苯二甲酸二辛酯(DOP)中加入抗静电剂SAS93、抗静电剂SN、导电炭黑、乙炔炭黑等助剂,采用熔融共混法制备了抗静电软质PVC片材;采用万能试验机、高绝缘电阻测量仪、场发射扫描电子显微镜研究了抗静电剂种类和组分对PVC片材的力学性能、体积电阻、表面电阻及形貌的影响。结果表明,添加0.5份的抗静电剂SAS93或SN均可使复合材料的体积电阻和表面电阻快速下降到10~7~10~8Ω;与SAS93相比,SN对软质PVC的硬度影响基本一致,SN对复合材料的拉伸性能影响更大;在软质PVC中添加20份的乙炔炭黑或导电炭黑时才能达到体积电阻和表面电阻为10~7~10~8Ω的效果;在添加30份乙炔炭黑或导电炭黑时,软质PVC的体积电阻和表面电阻下降到10~3~10~4Ω;添加20份乙炔炭黑或导电炭黑时,复合材料的表面电阻和体积电阻发生突变,即该炭黑的逾渗阈值为20份。 展开更多
关键词 抗静电性能 软质聚氯乙烯 乙炔炭黑 导电炭黑 抗静电剂 soft poly(vinyl chloride)
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Nitrogen doped carbon catalyzing acetylene conversion to vinyl chloride 被引量:12
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作者 Xingyun Li Xiulian Pan Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期131-135,共5页
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 vi... 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 mL.min-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. 展开更多
关键词 ACETYLENE HYDROCHLORINATION vinyl chloride MERCURY-FREE N doped carbon
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Vinyl chloride monomer production catalysed by gold: A review 被引量:8
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作者 Catherine J.Davies Peter J.Miedziak +1 位作者 Gemma L.Brett Graham J.Hutchings 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1600-1607,共8页
In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use o... In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use of different precursors and the addition to gold of a secondary metal as methods which attempt to improve these catalysts, and consider the nature of the active gold species. The vast majority of poly vinyl chloride (PVC) produced globally still uses a mercuric chloride as a cata‐lyst, despite the environmental problems associated with it. Due to the agreement by the Chinese government to remove mercury usage in the PVC industry over the course of the next few years there is an obvious need to find a replacement catalyst;the potential use of gold for this process has been well known for several decades and to date gold seems to be the best candidate for this, pri‐marily due to its superior selectivity when compared to other metals. 展开更多
关键词 GOLD ACETYLENE HYDROCHLORINATION Vinyl chloride monomer Poly vinyl chloride CATALYSIS
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Rare Earth Stearates as Thermal Stabilizers for Rigid Poly(vinyl chloride) 被引量:16
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作者 郑玉婴 蔡伟龙 +2 位作者 傅明连 王灿耀 张星 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第2期172-177,共6页
A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The res... A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The resulted revealed the higher stabilizing efficiency of the investigated rare-earth stearates as thermal stabilizers for rigid PVC compared with the thermal stabilizers for industry: calcium stearate, zinc stearate, butyl stannum mercaptide, phosphite esters, β-diketone and epoxidized sunflower oil. This was well illustrated by longer incubation period (T_S) values and lower rate of dehydrochlorination. The stable efficiency was affected by the nature of rare-earth element's individual electronic shell. The mechanism for the stabilizing effect of rare-earth stearates was proposed. The result was experimentally proved based on IR spectrum. 展开更多
关键词 poly(vinyl chloride) thermal dehydrochlorination rare-earth stearates stabilization mechanism conductivity method congo red test
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A Hybrid Membrane of Poly(vinyl alcohol) and Phosphotungstic Acid for Fuel Cells 被引量:10
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作者 李磊 王宇新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第5期614-617,共4页
Proton conducting membranes composed of phosphotungstic acid (PWA) and poly(vinyl alcohol) (PVA)were prepared. Conductivity and Fourier transform infrared spectrometer(FTIR) measurements show that most ofthe acid embe... Proton conducting membranes composed of phosphotungstic acid (PWA) and poly(vinyl alcohol) (PVA)were prepared. Conductivity and Fourier transform infrared spectrometer(FTIR) measurements show that most ofthe acid embedded are stable in the PVA matrix when the membrane is immerged in water or methanol solution atroom temperature. Conductivity of the composite membranes scatters around 10-3 S.cm-1 at room temperature.The methanol crossover through the membranes is about an order of magnitude lower than that through Nafion117 membrane. 展开更多
关键词 fuel cell proton conductor composite membrane poly(vinyl alcohol) phosphotungstic acid
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Synthesis and properties of acrylate latex modified by vinyl alkoxy siloxane 被引量:9
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作者 张心亚 孙志娟 +3 位作者 黄洪 黎永津 蓝仁华 陈焕钦 《Journal of Central South University of Technology》 EI 2007年第5期666-672,共7页
Acrylate latex modified by vinyl triisopropoxy silane (C-1706) was synthesized by seeded emulsion polymerization with anionic emulsifier sodium dodecyl sulphonate(SDS) and nonionic emulsifier OP-10 as the multiple emu... Acrylate latex modified by vinyl triisopropoxy silane (C-1706) was synthesized by seeded emulsion polymerization with anionic emulsifier sodium dodecyl sulphonate(SDS) and nonionic emulsifier OP-10 as the multiple emulsifiers at (78±2) ℃. The effects of different factors, such as the emulsifier, C-1706 monomer and its feeding manner on the properties of acrylate latex modified by C-1706 were investigated. The particle size distribution and the structure, the configuration, the weather durability and stain resistance of copolymer latex were characterized by particle size analyzer, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope(TEM), scanning electron microscope(SEM) and ultraviolet aging instrument respectively. The results show that SDS to OP-10 as multiple emulsifiers can lead to coordinated efficiency, the optimal emulsifier dosage is 2.4%?3.2%(mass fraction), and the mass ratio of SDS to OP-10 is 1?1? 1?2. The seeded emulsion polymerization can effectively introduce a organic-siloxane bonding in a macromolecule inter polymer, and the obtained acrylate latex modified by organic-siloxane possesses narrow distribution of particle size with mean diameter of 51.8?76.6 nm and has the excellent properties in weather durability and stain-resistance especially. 展开更多
关键词 vinyl alkoxy siloxane acrylate latex emulsion polymerization SYNTHESIS characterization
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