美国陶氏(DOW)化学公司的环氧树脂产品及其特点

<正>美国环氧树脂生产能力约为33万吨/年,陶氏化学公司,生产能力已超过10万吨/年,是美国主要生产环氧树脂厂家之一,其生产能力次于壳牌化学公司.最近美国陶氏化学公司最新资料报导了该公司所生产的环氧树脂系列品种的产品技术规格特点.这些品种系列主要有:双酚A型液态环氧树脂;双酚A型固态环氧树脂及其树脂溶液;     

丙烯酸酯／CTBN改性环氧树脂体系的性能研究

以CTBN化学改性环氧树脂与丙烯酸酯TPGDA直接共混固化.用FT-IR和粒度分布分析了改性环氧树脂的结构;比较了CTBN种类和TPGDA含量对改性环氧树脂力学性能的影响;SEM分析表明,改性后环氧树脂与CTBN和TPGDA形成了半互穿网络结构;DMA显示,TPGDA的加入增大了体系的储能模量,使损耗因子峰值向低温移动.     

木质素在环氧树脂合成中的应用进展

综述了木质素在环氧树脂合成中的应用进展。木质素用于环氧树脂合成的主要方式有三种:与通用环氧树脂共混;直接与环氧氯丙烷反应;经过酚化、氢解、丙氧基化和酯化等化学改性,再进行环氧化合成制备环氧树脂。木质素用于环氧树脂合成有利于实现木质素的高值化利用。     

环氧树脂及其涂料

200801011 水分散体及含水分散体的水性涂料;200801012 环氧树脂固化剂和涂料组合物;200801013 柔性陶瓷涂料及其制备方法;200801014 高性能环氧树脂涂料的研制;200801015 环氧树脂水性化化学改性的研究进展及其应用……     

行业信息

<正> 道化学公司在华环氧树脂厂投产 道化学公司宣布在华环氧树脂厂投产,该厂座落在张家港,年生产能力41000t,主要生产粉末涂料用固体环氧树脂、海洋和保护涂料用固体溶液环氧树脂以及电子层压板用溴化环氧树脂。据市场预测,这些产品在中国市场上将以两位数的速度增长,其产品将供应中国、亚洲国家及澳大利亚。     

新型纳米环氧树脂

<正>据"www.ptonline.com"报道,日本Kaneka(钟渊化学)株式会社公开了其最新研制技术:加入100nm级分散度核心橡胶颗粒的环氧树脂硬化技术,利用新技术成功研制出环氧树脂Kaneyi-MX。新产品纳米环氧树脂Kaneyi-MX采用独特的分子设计技术,在保证环氧树脂原有耐热性能基础上,提高了环     

道化学公司张家港环氧树脂厂顺利投产

美国道化学公司张家港环氧树脂工厂最近建成投产,该厂年产量为4.1万吨,所生产的固体环氧树脂产品主要用于粉末涂料;而环氧树脂固体溶液以及溴化环氧树脂产品则分别用于造船工业、工业防腐涂料和电子工业等部门。     

环氧树脂/碳纳米管复合材料制备及导电性能研究进展

简要介绍了环氧树脂/碳纳米管复合材料的组成以及碳纳米管在环氧树脂中的分散方法;综述了环氧树脂/碳纳米管复合材料的制备方法,包括溶液浇铸法、原位聚合法、化学改性法、混合固化剂辅助叠层法和树脂传递模塑法;总结了国内外对环氧树脂/碳纳米管复合材料导电性能的研究现状,并分析了影响其导电性能的因素,包括碳纳米管的比表面积、表面功能化和制备方法,剪切速率及固化条件等。     

室温固化耐热环氧胶粘剂的制备与性能研究

采用氨基硅油和液体端羧基丁腈橡胶(CTBN)对环氧树脂进行化学改性,制备出室温固化耐热环氧胶粘剂。探讨了氨基硅油和CTBN的加入量、环氧树脂种类等对胶粘剂粘接性能的影响。实验结果表明:用氨基硅油和CTBN共同改性环氧树脂制得的胶粘剂性能与末改性树脂相比有显著的提高;酚醛环氧树脂F-44和环氧树脂E-51进行复配时,所得胶粘剂的粘接性能较佳。     

环氧树脂膜的结构与性能评述(Ⅱ)

根据对环氧树脂膜及其涂料的研究应用效果,分两部分介绍环氧树脂化学结构和形态结构对性能的影响。第五部分评述环氧树脂膜的渗透指数与渗透介质对膜渗透性的关系;环氧树脂膜的结构参数与膜的物理机械性和耐烧蚀性的关系。     

不同化学结构环氧树脂电子束固化效果的分析

研究了化学结构对环氧树脂电子束辐射反应速率和辐射固化效果的影响。对于分子量相近的环氧树脂，反应速率大的环氧树脂体系最终达到的反应程度较高。酚醛型环氧树脂辐射反应活性高，固化后的高温模量及玻璃化转变温度高于双酚A型环氧树脂，但固化度沿辐射深度方向下降较快，脂环族环氧树脂的辐射反应活性小，在相同辐射条件下的固化效果差。缩水甘油胺结构的环氧树脂对于碘Wong盐引发的电子束辐射固化反应没有活性。     

New polymeric polyol for thermoset coatings: Superacid-catalyzed copolymerization of water and epoxy resins

Though free-radical emulsion polymerization has been studied extensively, published reports of cationic (i.e., acid-catalyzed) polymerizations of emulsified monomers are rare. It was recently discovered that treatment of an emulsion of liquid epoxy resin with select superacid catalysts yields a polymeric polyol. Catalysis with one percent perchloric acid at room temperature yields a product with a number average molecular weight of 1650, and a polydispersity of 5.0 as measured by GPC. The polyol’s structure differs from that of conventional high molecular weight epoxy resins prepared by the advancement process in several ways, including the incorporation of two glycidyl units in the repeat unit. In essence, the product is a copolymer of the epoxy resin and water, in which water is incorporated in the repeat unit structure by reaction with two epoxide groups. A similar product can be prepared by solution polymerization, where the molecular weight is controlled by the ratio of water to epoxy resin. The product was shown to have lower levels of residual bisphenol-A diglycidyl ether (BADGE) and bisphenol-A than conventional advanced epoxy resins. Polyols prepared by these new processes were crosslinked with melamine-formaldehyde resins in waterborne coating formulations which were free of added cosolvent, as well as solventborne coating formulations. The coatings developed excellent solvent resistance at lower bake temperatures than traditional epoxy resins. Presented at the 79th FSCT Annual Meeting in Atlanta, GA, Nov. 5–7, 2001. 7201 Hamilton Blvd., Allentown, PA 18195-1501.     

Study of the condensation products of abietic acid with formaldehyde

Abietic acid and paraformaldehyde, taken in various molar ratios, were condensed in acid catalysis (p-toluenesulfonic acid). Toluene was used both as reaction medium and carrier for aqueous condensate. The obtained polymeric products (resins) were characterized by determination of acid number, melting point, molecular weight and viscosity. Spectral methods, e.g. I. R. and ¹H-NMR, were also used in the same scope. The experimental data evidence the fact that abietic acid is a substance with a functionality of minimum 3 as against formaldehyde. There have been obtained some condensation products with three-dimensional structure and low molecular weight. The polymerization average degree of the resins was found to be 3, although some fractions with polymerization average degree of 6 have been observed. The chemical bonds established between the structural units can be of both methylenic and dimethylene ether type, depending on the molar ratio of reacting substances.     

NMR法测定环氧树脂聚合度和官能度的研究

根据环氧树脂1H-NMR谱中环氧基、苯基、亚次氧甲基、甲基的质子数与相应峰面积的比例关系,可同时求得环氧树脂的聚合度n和官能度Fn.将甲基法和苯基法测定的聚合度n和官能度Fn与文献法和商品标示值做比较,由甲基峰面积与苯基峰面积的比值关系得出苯基法比甲基法更合理.甲基法或苯基法测定数均分子量Mn和环氧当量EEW依赖于聚合...     

Synthesis of rosin‐based flexible anhydride‐type curing agents and properties of the cured epoxy

BACKGROUND: Although rosin acid derivatives have received attention in polymer synthesis in recent years, to the best of our knowledge, they have rarely been employed as epoxy curing agents. The objective of the study reported here was to synthesize rosin‐based flexible anhydride‐type curing agents and demonstrate that the flexibility of a cured epoxy resin can be manipulated by selection of rosin‐based anhydride‐type curing agents with appropriate molecular rigidity/flexibility. RESULTS: Maleopimarate‐terminated low molecular weight polycaprolactones (PCLs) were synthesized and studied as anhydride‐type curing agents for epoxy curing. The chemical structures of the products were confirmed using ¹H NMR spectroscopy and Fourier transform infrared spectroscopy. Mechanical and thermal properties of the cured epoxy resins were studied. The results indicate that both the epoxy/anhydride equivalent ratio and the molecular weight of PCL diol play important roles in the properties of cured resins. CONCLUSION: Rosin‐based anhydride‐terminated polyesters could be used as bio‐based epoxy curing agents. A broad spectrum of mechanical and thermal properties of the cured epoxy resins can be obtained by varying the molecular length of the polyester segment and the epoxy/curing agent ratio. Copyright © 2009 Society of Chemical Industry     

Recent developments in two-pack water-based epoxy coatings

In recent years new curing agent technology has been developed which allows water-based curing agents to be introduced into high performance coating, these are classified according to the type of epoxy resin used. Type I utilises low molecular weight, liquid epoxy resins and Type II pre-formed dispersions of higher molecular weight solid epoxy resins. The chemical composition of the binder of water-borne epoxy coatings plays a critical role in their performance properties, hence some of the structural properties of the amine hardeners will be reviewed. New curing agents will be discussed which demonstrate the versatility these products can offer to the coating formulator. Performance data of clear coats and anti-corrosive primers confirm the applicability of the new systems for the long term protection of steel and concrete surfaces.     

Effect of Xylene Formaldehyde Resins on Epoxy Resin Adhesive

The effect of some types of xylene formaldehyde on epoxy resin adhesive is studied. Xylene formaldehyde resin or modified xylene formaldehyde resins are mixed into liquid epoxy resin and curing properties of the blends, their adhesive properties and the dispersion state of xylene formaldehyde resin in cured adhesive film are examined. The results obtained are as follows.

1) Generally, by the addition of xylene formaldehyde resins, the degree of curing of blends are decreased, but pot life is prolonged, and tensile shear strength of steel bonds is increased.

2) It is observed that effects of the amount of xylene formaldehyde resins and curing condition on tensile shear strength vary with the kind of xylene formaldehyde resin, because of the difference in chemical structure of xylene formaldehyde resins and their reactivity to epoxy resin.

3) It is found that a limited region of compatibility, between 80 and 100 phr, exists for 100% xylene formaldehyde resin in epoxy resin. It is also found that joint strength is reduced with higher viscosity and molecular weight of 100% xylene formaldehyde resin in the case of 80 phr blends, and that these results have some relation to the dispersion state of xylene formaldehyde resin in epoxy resin, judging from the cured adhesive film observed under a phase contrast microscope.     

Structural modification of brominated epoxy resins by reaction with phosphoric or poly(phosphoric acid)

A modification process of some commercial brominated epoxy resins by reacting them with phosphoric or poly(phosphoric acid) is described. The influence of the reactants ratio on the thermal stability of the modified resins was investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The resin obtained from complete esterification of phosphoric acid showed the highest thermal stability. In addition, the resins prepared by reacting phosphoric acid with brominated epoxy resins of different molecular weight were thermally characterized by DSC and TGA. Most of the modified resins were thermally more stable than the corresponding unmodified resins. The chemical reactions that possibly take place during the process are discussed. Furthermore, the structure of the modified resins was investigated by Fourier-transform-infrared (FT–IR) spectroscopy.     

偏氯乙烯-氯乙烯悬浮共聚树脂的分子质量及分布

在5L聚合釜中合成了偏氯乙烯(VDC)-氯乙烯(VC)悬浮共聚树脂,研究了聚合温度、转化率、单体配比和助剂对分子质量及分布的影响．结果表明,共聚树脂的分子质量与聚合温度的关系符合Arrhenius方程,其综合活化能为-32．877kJ／mol;聚合物的特性黏数在高转化率阶段基本不变;分子质量随着单体配比中VC含量的增加而降低、分子质量分布也有一定的波动;聚合前加入助剂对共聚树脂的分子质量及分布影响不大。     

Preirradiation‐induced emulsion graft polymerization of glycidyl methacrylate onto poly(vinylidene fluoride) powder

An epoxy‐group‐containing monomer, glycidyl methacrylate (GMA), was grafted onto poly(vinylidene fluoride) powder via preirradiation‐induced emulsion graft polymerization. The existence of graft chains was proven by chemical structure characterization with Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy analysis. The degree of grafting was calculated by means of fluorine content analysis. A kinetic study indicated that, with the emulsion graft polymerization system, the GMA conversion rate was high, exceeding 80%. The variation in the molecular weight of the grafted polymer was measured by gel permeation chromatography, and its crystallinity was investigated with differential scanning calorimetry. The epoxy groups in graft chains were found to be suitable for further chemical modification. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010