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1.
收集了2001年7月到2002年6月有关国外塑料工业的相关期刊资料,介绍了2001年到2002年国外塑料工业的发展情况,提供了世界各地域塑料原材料的产量及构成比,日本、美国、加拿大、德国、法国、比利时、墨西哥、芬兰、西班牙等国家的树脂产量、消费量及增长率,以及日本、西欧、北美等地区的不同品种塑料原料消费量和增长率统计.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)不同品种的顺序,对树脂的产量、消费量及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等有关技术作了详细的介绍.  相似文献   

2.
收集了2006年7月~2007年6月世界塑料工业的相关资料,介绍了2006~2007年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

3.
1998~1999年国外塑料工业进展   总被引:3,自引:0,他引:3  
收集了 1998年 7月到 1999年 6月国外塑料工业相关期刊资料 ,介绍了 1998~ 1999年国外塑料工业进展。提供了日本、美国、加拿大、德国、法国、比利时、意大利、英国、西班牙、匈牙利、马来西亚等国通用热塑性树脂、工程塑料、通用热固性树脂、特种工程塑料的产量和增长率 ,提供了美国、日本、德国、韩国、法国、比利时、荷兰、意大利和其他国家以及亚洲、欧洲、北美洲、中南美洲、非洲和大洋洲等地域的树脂产量及构成比 ,此外还提供了中国台湾的树脂产量。按通用热塑性塑料、通用热固性塑料、通用工程塑料和特种工程塑料分类 ,对其合成工艺、树脂品种延伸、新的应用开发等工业技术作了详尽的介绍  相似文献   

4.
崔小明 《中国橡胶》2005,21(10):10-14
丁基橡胶()是世界上第四大合成橡胶(SR)IIR胶种,是异丁烯和异戊二烯在Friedel-Craft催化剂作用下进行阳离子聚合反应的产物。由于丁基橡胶具有优良的气密性和良好的耐热、耐老化、耐臭氧、耐溶剂、电绝缘、减震及低吸水等性能,使得其在内胎、水胎、硫化胶囊、气密层、胎侧、电线电缆、防水建材、减震材料、药用瓶塞、食品(口香糖基料)、橡胶水坝、防毒用具、粘合剂、内胎气门芯、防腐蚀制品、码头护舷、桥梁支撑垫以及耐热运输带等方面具有广泛的应用。一、世界丁基橡胶生产现状及市场前景1.生产现状目前,世界上只有美国、德国、俄罗斯、…  相似文献   

5.
树脂基复合材料成型工艺研究进展   总被引:3,自引:0,他引:3  
主要综述了树脂基复合材料的几种成型工艺,包括RTM、VARTM、CRTM、LRTM、RFI、VARI、SCRIMP、SRIM、TERM,各自的发展现状、成型原理、特点等.  相似文献   

6.
化学品仓库集中存放着许多化工产品,这些产品性质复杂,多数有易爆、易燃、有毒、有腐蚀性的特点,扑救这类化学品的火灾是一项比较复杂的工作。如不能用水(包括水蒸气和含水的泡沫剂)扑救的化学品就有金属钠、钾、钙、镁、钍、铝粉、铝镁合金、氰化钠、硼氢化物、电石、磷化钙、发烟硫酸、氯磺酸、三氯化磷、五氯化二磷、无水氯化铝、过氧化钠、氯化硫酰、四氯化硅、五氨化锑、氯乙酰、苯基氯硅烷等忌水物质。  相似文献   

7.
收集了2010年7月~2011年6月世界塑料工业的相关资料,介绍了2010~2011年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、不饱和聚酯树脂、环氧树脂、聚氨酯)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。  相似文献   

8.
赵罡 《中华手工》2018,(6):42-49
自然界,为人类提供了生存、生活,以及进行创造的物质基础。人们在自然界的劳动实践中,获取了竹、木、柳、藤、草、棉、革、漆、土、玉、石、陶、瓷、金、银、铜、铁、锡等成为生活用品的材料。随着造物活动的扩大,人们也创造了与这些材质相适应的雕、镂、刻、削、染、缝、绘、髹、铸、琢、磨等工艺。  相似文献   

9.
<正>河南省沁阳市沁龙化学防腐有限公司是从事研制生产多功能新型螺旋溜槽、摇床、旋流分级机、磁选机、浮选机、搅拌槽、打砂机、玻璃钢冷却塔、风机、管道、防腐贮罐等多种产品的专业公司,已有近三十年的生产历史,通过了ISO9001:2000质量体系认证。主导产品为多功能新型螺旋溜槽、摇床,是选别有色金属、黑色金属、非金属、贵重金属的理想选矿设备,如金矿、银矿、沙金矿、锡矿、钛铁矿、硫铁矿、赤铁矿、褐铁矿、铬铁矿、钨矿、钽泥矿、煤矿、独居石、蓝宝石、重晶石、金红石、锆英石、硅砂等。现有8000多台设备在全国各地矿山使用。在鞍钢、马钢、首钢、包钢、唐钢、安钢、武钢、柳  相似文献   

10.
10月27日-11月20日,笔者一行4人对河南商丘、安徽毫州、阜阳3个市的市区和郊区泛家居行业进行了普查,共走访调查经销商1250多家,走访各种规模的建材城、建材街、家具市场、装饰建材市场10个,填写《全国泛家居行业经销商普查表》1200多份,调查涵盖陶瓷、卫浴、家具、橱柜、衣柜、厨房电器、五金锁具、楼梯、门窗、地板、涂料、淋浴房、家装、红木、木雕、吊顶、竹家居、石材、管材、建材、水暖、太阳能、灯饰LED、饰品、地毯、木制品、铁艺、布艺、墙纸、家纺、晾衣架、背景墙、隐形纱窗等30多个泛家居细分行业。  相似文献   

11.
The formation of oxazolidone from 9,10-epoxyoctadecane and phenylisocyanate was studied. One branch of epoxidized vegetable oil with one epoxy group per chain corresponds to 9,10-epoxyoctadecane. This model could explain the probability of oxazolidone formation from natural oil-derived epoxides. Epoxidized natural oils are TG consisting of glycerin and three FA with or without one to three epoxy groups in the middle of the chain. To study oxazolidone formation from an internal epoxy group without possible interference from the side reactions on the ester group, 9,10-epoxyoctadecane was selected as the most appropriate model compound. Epoxy groups in the middle of allong aliphatic chain are of low reactivity toward isocyanates, and preparation of oxazolidones requires fairly harsh conditions such as high temperatures and catalysts, which also promote side reactions. The dominant side reaction is rearrangement of the epoxy groups. We found that the direction and magnitude of the rearrangement and the yield of any particular product depended on the catalyst used. Lithium chloride, aluminum trichloride, and zinc iodide catalyzed oxazolidone formation, along with the catalysis of side reactions such as ketone and carbonate formation. Aluminum trichloride showed the highest conversion of 9,10-epoxyoctadecane to oxazolidone. Aluminum triisopropoxide, triphenylantimony iodide, and imidazole did not catalyze the formation of oxazolidone. They were effective as catalysts of epoxy group rearrangement and promoted the formation of hydroxyl, ketone, and carbonate compounds. Hydroxyl groups reacted with isocyanate to produce urethane.  相似文献   

12.
异氰酸酯/环氧树脂的固化机理   总被引:2,自引:0,他引:2  
左浚茹  程珏  林欣  张军营 《化工学报》2012,63(8):2629-2634
详细研究了异氰酸酯/环氧树脂体系的固化反应和固化机理。采用差示扫描量热法(DSC)和红外光谱法(FTIR)跟踪了异氰酸酯/环氧树脂固化反应过程,定量分析了异氰酸酯、环氧基团和新生成的异氰脲酸酯和口恶唑烷酮的变化。DSC分析结果表明,DSC曲线上出现3个放热峰,说明固化过程中存在至少3种反应;FTIR分析结果表明,在140℃以下固化体系主要发生异氰酸酯的三聚反应生成三嗪环(异氰脲酸酯);在200℃下,异氰酸酯-NCO基团与环氧基团开环反应生成口恶唑烷酮;在230℃ 下,三嗪环(异氰脲酸酯)进一步与环氧基团开环反应生成口恶唑烷酮。研究了不同温度下环氧基团、异氰酸酯基团、异氰脲酸酯基团、口恶唑烷酮基团随反应时间的变化规律。  相似文献   

13.
Isocyanurate–oxazolidone (ISOX) polymers have been reported as a novel, intrinsically self-healable thermoset, and their healing mechanism under the effect of nucleophiles, such as tertiary amines and pyridines during polymerization, is thoroughly investigated in this study. This work provides evidence that the healing behavior of the polymers results part from the transformation of isocyanurate to oxazolidone on the fracture surfaces of the ISOX polymers at elevated temperatures. The isocyanurate transformation is characterized by chemical composition of the ISOX polymers before and after a predetermined healing procedure, through a combination characterization of Fourier transform infrared spectroscopy and carbon nuclear magnetic resonance spectroscopy. From the chemical composition of the ISOX polymers, an increased oxazolidone fraction is observed after the healing event, which verifies the hypothesized healing mechanism. By correlating the change in oxazolidone fraction in the polymers during the healing event, with the corresponding healing performance of the polymers, healing efficiencies of the polymers are shown to be inversely proportional to the ratio of oxazolidone to isocyanurate in the polymers. The transformation to oxazolidone is also shown to be dependent on two variables, nucleophilicity of the polymerization catalyst and duration of the postcure. The isocyanate and epoxide polymerization mechanism in the presence of nucleophiles is also investigated to explain the effect of the catalyst nucleophilicity on the chemical composition as well as the healing performance of the ISOX polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48698.  相似文献   

14.
Isocyanurate–oxazolidone polymers were synthesized by using various reactant stoichiometry of a diglycidyl ether of bisphenol-A (DGEBA) and a polymeric diphenyl methane diisocyanate (pMDI). The reaction was catalyzed by tris-2,4,6-dimethylaminoethylphenol (Ancamine K54). The effects of stoichiometry that the reaction had on the molecular structure and mechanical and thermomechanical properties were evaluated. Two main structures obtained from the reaction of DGEBA with pMDI, namely isocyanurate and oxazolidone, were clearly shown by Fourier transformed infrared spectroscopy (FTIR) analyses. It was found that the amount of DGEBA present determines the amount of oxazolidone formed. Where excess DGEBA was used, structural transformation reaction from isocyanurate to oxazolidone was observed. The amount of pMDI, on the other hand, influenced the amount of isocyanurate structure formed. As the relative amounts of isocyanurate and oxazolidone contents changed with stoichiometry of the reactants, the effects on the crosslink density in the samples were clearly shown by both mechanical and thermomechanical measurements. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 879–888, 2001  相似文献   

15.
A new type of rigid polyurethane foam was produced by incorporating oxazolidone heterocyclic rings on to polyurethane backbones. Epoxidized diethanolamides were synthesized by reacting palm oil blends of epoxidized palm olein and refined bleached deodorized palm kernel olein with diethanolamine to produce rigid polyurethane foams. Epoxides, retained in the diethanolamides, reacted with isocyanate during foam production in the presence of AlCl3–THF complex catalyst to form oxazolidone linkages in the polyurethane network. The carbonyl stretch of oxazolidone was identified at 1,750 cm−1 through Fourier Transform Infra Red analysis. Chemical modifications of the polyurethane network also improved the thermal and mechanical properties of the foams. In addition, isocyanate index 1.4 was determined to be the most suitable in the production of foams from this newly synthesized epoxidized diethanolamides.  相似文献   

16.
Polyol or polysiloxane thermoplastic polyurethanes (TPU) were used to reduce micro-cracking in cresol–formaldehyde novolac epoxy resin cured with phenolic Novolac resin for electronic encapsulation application. A stable dispersion of TPU particles in an epoxy resin matrix was achieved via the epoxy ring opening with isocyanate groups of urethane prepolymer to form an oxazolidone. The effects of structure and molecular weight of TPU in reducing the stress of electronic encapsultant were investigated. The mechanical and dynamic viscoelastic properties and morphologies of TPU modified epoxy networks were also studied. A “sea-island” structure was observed via SEM. The dispersed polysiloxane TPU rubbers not only effectively reduce the stress of cured epoxy resins, by reducing flexural modulus and the coefficient of thermal expansion, but also increase the glass transition temperature because of the rigid oxazolidone structure formation. Electronic devices encapsulated with the polysiloxane TPU modified epoxy molding compounds exhibited excellent resistance to the thermal shock cycling test and resulted in extended device life. © 1996 John Wiley & Sons, Inc.  相似文献   

17.
环氧/异氰酸酯树脂的共固化反应研究   总被引:2,自引:0,他引:2  
本文采用差示扫描量热法(DSC)及付立叶红外光谱法(FTIR)等手段研究了环氧树脂与异氰酸酯共固化反应。研究发现催化剂 2,4-EMI对异氰酸酯的三聚反应和噁唑烷酮的生成反应均有催化作用,对噁唑烷酮的生成反应的催化尤为明显;在反应过程中,率先生成的PIS开环与环氧基因反应生成POX;树脂中的I/E值在1.2~2之间才能使树脂中的官能团反应较为完善,从而有利于其各项性能的提高。  相似文献   

18.
Summary Adducts of trichloro and triisothiocyanato borane with alkyldimethylamines are effective latent catalysts for epoxy homopolymerization. The lower stability triisothiocyanato borane adducts initiated the polymerization at lower temperatures than the chloro derivatives. In both cases the borane moiety was converted into [B(OR)4]- by reaction with the oxirane ring initiating the reaction by the formation of cations. Free amine was detected in the curing resin but was not directly involved in the polymerization mechanism. The formation of oxazolidone rings was observed when triisothiocyanato borane adducts were used. The behaviour of some of the decomposition products of the adducts was also examined.  相似文献   

19.
Reactions taking place in a system consisting of a diepoxide (DGEBA, diglycidylether of bisphenol A) and a diisocyanate (TDI 80 : 20, toluene diisocyanate), catalyzed by a tertiary amine (BDMA, benzyldimethylamine), were followed by differential scanning calorimetry (DSC), infrared spectroscopy (FTIR), and chemical titration of isocyanate groups in the pre-gel stage. It was found that the main reactions took place in series, in steps of increasing temperature: (i) isocyanurate formation, (ii) epoxy-isocyanate reaction leading to oxazolidone rings, and (iii) isocyanurate decomposition by epoxy groups producing oxazolidone rings. Isocyanurate rings were stable in the presence of epoxides and an isocyanate excess [reaction (ii) was faster than (iii)]. Epoxy homopolymerization (secondary reaction) occurred in parallel with steps (ii) and (iii). Step (i) took place by two different mechanisms and led to a maximum conversion, possibly limited by topological restrictions. A kinetic study of TDI trimerization in the presence of an equimolar amount of DGEBA and variable amounts of BDMA led to a third-order regression with an activation energy E = 43 kJ/mol. © 1995 John Wiley & Sons, Inc.  相似文献   

20.
Reaction of a diepoxide with a diisocyanate in bulk   总被引:1,自引:0,他引:1  
Summary Reactions between a diepoxide and a diisocyanate can lead to copolymers having isocyanurate and oxazolidone rings in their chemical structure. Using Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR), we have studied the influence of catalysts such as an imidazole or a blocked isocyanate on the polymer formation. We have identified the nature of the exotherms observed in DSC experiments with the aid of FTIR spectroscopy and observed the influence of the molar ratio of the functional groups and the amount of catalyst. We have compared the influence of these catalysts with results obtained previously with a tertiary amine.  相似文献   

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