插层聚合制备环氧树脂/蒙脱土灌封材料的研究

采用阳离子交换的方法对蒙脱土进行了有机化处理，使蒙脱土由亲水性变成亲油性，并且使其层间距由原来的1．2m扩大到2．2nm。采用X射线衍射仪研究了有机蒙脱土在环氧树脂中的剥离行为。制备了环氧树脂／蒙脱土灌封材料并测试了其性能。试验结果表明，环氧树脂与有机蒙脱土的相容性好，蒙脱土在环氧树脂中完全剥离；环氧树脂／蒙脱土灌封材料的电学性能、力学性能、热性能以及吸水率与纯环氧树脂固化物相比均有不同程度的提高和改善。     

有机蒙脱土改性无溶剂环氧涂料的研究

利用熔融插层法将有机蒙脱土引入环氧树脂体系，制备出含有纳米分散蒙脱土的无溶剂环氧涂料。研究了有机蒙脱土和环氧树脂不同的插层工艺、有机蒙脱土在环氧树脂中插层和剥离的效果、以及通过改变有机蒙脱土的含量，对漆膜的性能的影响。分析有机蒙脱土在无溶剂环氧防腐蚀涂料中的作用并优化配方。研究证明，加入有机蒙脱土以后，在不增加无溶剂环氧涂料黏度和不降低漆膜力学性能的基础上，耐化学腐蚀性能有了明显提高。     

有机蒙脱土/环氧树脂胶的研究

通过阳离子交换，对蒙脱土进行有机化．并研究了混合方式和固化工艺对有机蒙脱土／环氧树脂胶力学性能的影响。研究表明，有机蒙脱土／环氧树脂胶与纯环氧树脂胶相比，其力学性能、耐水性和耐其他介质性得到较大提高。     

纳米蒙脱土/环氧树脂胶粘剂最佳组分的优化选择

将有机化处理后的蒙脱土作为填料，通过插层复合的方法制备出纳米蒙脱土／环氧树脂胶粘剂，进行了拉伸强度、硬度及XRD测试，并与粉煤灰、未处理蒙脱土作填料的环氧胶粘剂进行了性能对比。，试验结果表明，当加入质量分数5％的有机蒙脱土时，环氧胶粘剂的剪切强度达到21．6MPa；X射线衍射结果表明，用该法制得的胶粘涂层内部蒙脱土片层已被剥离，属于纳米复合胶粘剂；通过对比力学性能及密度，加入有机蒙脱土的环氧树脂胶粘剂涂层综合性能要优于一般环氧树脂胶粘剂。     

环氧树脂插层纳米复合材料固化动力学研究

运用自制的有机蒙脱土，采用浇模固化成型法制备环氧树脂／二乙烯三胺／有机蒙脱土纳米复合材料，对固化产物利用XRD（X射线衍射）分析有机蒙脱土的层间距变化，确定产物为插层型的纳米复合材料，并用DSC（差示扫描量热法）跟踪环氧树脂固化行为。运用Kissinger,Flynn-Wall-Ozawa,Crane方法对环氧树脂的固化反应过程进行分析，求出活化能和反应级数等动力学以在数。结果发现，加入有机化蒙脱土后使固化反应活化能和频率下降，从而有利于固化工艺的实现，便于纳米复合材料实际应用。     

纳米有机蒙脱土改性邻甲酚醛环氧树脂的研究

利用插层复合技术制备了邻甲酚醛环氧树脂／蒙脱土纳米复合材料，对固化产物利用X射线衍射(XRD)分析有机蒙脱土的层间距变化。通过对复合材料的力学性能测试表明，少量有机化蒙脱土的加入可以较大地提高材料的拉伸强度和冲击强度，起到了同时增韧增强的作用。并且环氧树脂／蒙脱土复合材料的热分解温度和热变形温度也有明显提高。     

水性环氧树脂包覆有机蒙脱土制备木材胶粘剂

摘要：水性环氧树脂通常含有水溶性分子或分子链，导致在高温和潮湿条件下作为木材胶粘剂时耐水性及力学性能较差。采用有机改性的纳米蒙脱土改性水性环氧树脂增强水性环氧树脂胶粘剂的耐水性及力学性能。并通过乳液包覆蒙脱土的方法与直接共混的方法对比，研究了不同添加量有机蒙脱土（0%，3%，6%，9%）对胶粘剂性能的影响。胶粘剂的耐水性及力学性能通过测量胶粘剂在干燥及潮湿条件下的剪切强度来表示。通过TGA、SEM、TEM、DSC研究了复合胶粘剂的热稳定性和结构。结果表明，在水性环氧树脂中添加有机改性的纳米蒙脱土，可以有效地提高胶粘剂的粘结强度，此外，采用乳液包有机覆蒙脱土的方法比直接共混的方法制备得到胶粘剂，有机蒙脱土在胶粘剂中分布更均匀，具有更优异的力学性能，说明有机蒙脱土在复合材料中的分散质量是影响复合胶粘剂性能的主要原因。     

熔融共混法制备聚丙烯/蒙脱土复合材料

文章选用三种方法制备了蒙脱土/聚丙烯复合材料：（1）有机蒙脱土-PPMA母料法;（2）有机蒙脱土、PP、PPMA直接熔融共混法;（3）经环氧树脂预处理的有机蒙脱土、PP、PPMA直接熔融共混法。通过XRD和TEM考察了蒙脱土在体系中的分散状态,结果表明：随着体系中蒙脱土含量的增加,蒙脱土的分散效果逐渐变差,在同一蒙脱土含量下,环氧树脂预处理有机蒙脱土法制备的复合材料中蒙脱土的分散状态最好。     

负载羧基有机蒙脱土制备环氧树脂纳米复合材料(英文)

用椰油酰胺丙基甜菜碱(CAB)制备了1种负载羧基的有机蒙脱土,并将这种有机蒙脱土加入甲基四氢苯酐固化环氧树脂体系中制得环氧树脂/蒙脱土纳米复合材料。采用XRD衍射和透射电镜TEM研究了蒙脱土有机化前后和在纳米复合材料中的片层结构和形态。用TGA研究了纳米复合材料的热稳定性能。结果表明,制备的负载羧基蒙脱土充分插层且很容易分散在环氧树脂中得到纳米复合材料。其热稳定性和有机蒙脱土在树脂中的分散状态有关。     

纳米插层聚氨酯改性环氧树脂性能研究

采用聚氧化丙烯二醇(N210和N220)、2，4-甲苯二异氰酸酯(TDI)、有机纳米蒙脱土(OMMT)等为原材料，分别制备了相应的聚氨酯预聚体和有机蒙脱土纳米插层聚氨酯预聚体，并以此对环氧树脂E44进行化学共聚改性，系统地研究了改性环氧树脂复合材料的力学性能等。研究表明，有机蒙脱土纳米插层聚氨酯能大幅度提高环氧树脂复合材料的韧性等，比相应的聚氨酯预聚体改性环氧树脂具有更好的效果。     

有机蒙脱石增强环氧树脂纳米复合材料的研究

介绍以有机蒙脱石作为增强组分的环氧树脂纳米复合材料的制备及其性能表征。结果表明,十六胺处理的蒙脱石层离以1－100nm尺度分散于环氧树脂基体中,复合材料的物性得到提高,当蒙脱石含量比在3％时,马丁耐热提高9℃,冲击强度提高了122％,但进一步增加蒙脱石的含量比,上述两性能不升反降。     

有机蒙脱土改性环氧树脂胶粘剂的制备工艺优化设计

采用不同碳链的季铵盐阳离子作为插层剂与蒙脱土层间的无机阳离子(Ca2+)交换,制备出系列有机蒙脱土,用有机蒙脱土对环氧树脂进行改性,制备了纳米有机蒙脱土/环氧树脂结构胶,同时,用4因素3水平正交试验设计对关键配料参数进行了优化,并对结构胶的剪切强度和冲击强度进行了测试。研究表明,优化配制的纳米改性环氧树脂胶粘剂是一种高性能的结构胶粘剂,其钢-钢剪切强度可达29.2 MPa,冲击强度可达33.8 MPa,有效地改善了环氧树脂胶粘剂的粘接性能。     

纳米蒙脱土插层聚合改性环氧树脂

以纳米蒙脱土为原料,采用插层聚合法制备了改性增韧环氧树脂.通过正交实验考查了混合时间、混合温度、蒙脱土类型、蒙脱土含量对改性环氧树脂断裂伸长率的影响.实验结果表明混合时间对改性环氧树脂的断裂伸长率影响最大,当混合时间为2h,混合温度为70℃,采用DK1类型的蒙脱土,添加量为2%时,制备的改性环氧树脂断裂伸长率为12.1...     

Epoxy‐montmorillonite clay nanocomposites: Synthesis and characterization

Nanocomposites of epoxy resin with montmorillonite clay were synthesized by swelling of different proportions of the clay in a diglycidyl ether of bisphenol‐A followed by in situ polymerization with aromatic diamine as a curing agent. The montmorillonite was modified with octadecylamine and made organophilic. The organoclay was found to be intercalated easily by incorporation of the epoxy precursor and the clay galleries were simultaneously expanded. However, Na‐montmorillonite clay could not be intercalated during the mixing or through the curing process. Curing temperature was found to provide a balance between the reaction rate of the epoxy precursor and the diffusion rate of the curing agent into the clay galleries. The cure kinetics were studied by differential scanning calorimetry. The exfoliation behavior of the organoclay system was investigated by X‐ray diffraction. Thermogravimetric analysis was used to determine the thermal stability, which was correlated with the ionic exchange between the organic species and the silicate layers. The morphology of the nanocomposites was evaluated by scanning electron microscopy. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2201–2210, 2004     

环氧树脂/蒙脱土纳米复合材料的性能及增韧机理

将有机蒙脱土添加到环氧树脂中,制备环氧树脂/纳米复合材料,考察复合材料的力学和热学性能,研究发现,5%的添加量可以使环氧树脂的冲击、断裂强度得到大幅度的提高,添加3%的有机蒙脱土,热变形温度提高了6.1℃.通过SEM和AFM,对环氧树脂/蒙脱土纳米复合材料冲击断口进行微观研究,发现断口呈现出明显的韧性断裂.结合微观形貌,对有机蒙脱土增韧环氧树脂的各种机理进行探讨,认为符合基体剪切屈服增韧机理.     

三乙烯四胺固化有机蒙脱土/环氧树脂复合体系的研究

以三乙烯四胺作为EP(环氧树脂)的常温固化剂制备EP/OMMT(有机蒙脱土)/三乙烯四胺纳米复合材料。采用X射线衍射(XRD)法,差示扫描量热(DSC)法等手段研究了不同配方对EP/OMMT/三乙烯四胺固化体系的凝胶时间、力学性能、热性能及OMMT的插层剥离行为等影响。结果表明:对EP/OMMT/三乙烯四胺复合材料而言,90~120℃固化体系的OMMT剥离与插层效果优于室温固化体系;当固化温度为120℃时,EP/OMMT/三乙烯四胺复合材料的耐湿热性能和弯曲强度均优于常温固化体系;EP/OMMT/三乙烯四胺复合材料经常温固化24 h后,其冲击强度比纯EP体系提高了7%~12%。     

The role of nanofillers on (natural rubber)/(ethylene vinyl acetate)/clay nanocomposite in blending and foaming

Nanocomposite foams were fabricated from 60/40 wt% ethylene vinyl acetate (EVA)/natural rubber (NR) blends by using azodicarbonamide as a blowing agent. Two different nanofillers (sodium montmorillonite and organoclay) were employed to study their effects on foam properties. The results were also compared with conventional (china clay)‐filled foams. Transmission electron microscopy, X‐ray diffraction, scanning electron microscopy, and three‐dimensional Microfocus X‐ray computed tomography scanning analysis were performed to characterize the EVA/NR blend morphology and foam structures. The results revealed that the nanofiller acted as a blend compatibilizer. Sodium montmorillonite was more effective in compatibilization, generating better phase‐separated EVA/NR blend morphology and improving foam structure. Higher filler loading increased the specific tensile strength of rubber foams. The rubber nanocomposite foam showed superior specific tensile strength to the conventional rubber composite foam. The elastic recovery and compressive strength of the nanocomposite foams decreased with increasing filler content, whereas the opposite trend was observed for the conventional composite foams with china clay. The thermal conductivity measurement indicated that the nanofiller had better beneficial effect on thermal insulation over china clay filler. From the present study, the nanofillers played an important role in obtaining better blend morphology as compatibilizer, rather than the nucleating agent and the nanofiller content of 5 phr (parts by weight per hundred parts of rubber) was recommended for the production of EVA/NR nanocomposite foams. J. VINYL ADDIT. TECHNOL., 21:134–146, 2015. © 2014 Society of Plastics Engineers     

Diffusion behavior of water and sulfuric acid in epoxy/organoclay nanocomposites

The research on polymer‐layered silicate nanocomposites is currently an expanding field of study because they often exhibit a wide range of improved properties over their unmodified starting polymers. Epoxy/organoclay nanocomposites have been prepared by intercalating epoxy into the organoclay montmorillonite. The intercalation and/or exfoliation of the clay within the nanocomposite were monitored using X‐ray diffraction and transmission electron microscopy. Diffusion was studied through epoxy samples containing up to 10 phr of organically treated montmorillonite following the gravity method. The water and sulfuric acid diffusion within the epoxy‐based nanocomposites were evaluated in terms of diffusivity, weight change and penetration depth of the sulfuric acid element S as function of immersion time and immersion temperature. An investigation of the resistance of epoxy nanocomposite to a corrosive environment by immersion into sulfuric acid at elevated temperature was performed. The effect of the degree of exfoliation of the clay on moisture barrier effect and corrosion resistance is specifically studied. The data has been compared to those obtained from the neat epoxy resin to evaluate the diffusion properties of the nanocomposites. It was found that the diffusion of water and that of acid do not obey Fick's law, and that the higher the organoclay content the higher weight change was obtained. The presence of the organoclay enhanced the diffusivity and delayed the penetration of the sulfuric acid. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

The Nucleating Effect of Montmorillonite on Crystallization of PET/Montmorillonite Nanocomposite

Poly(ethylene terephthalate) (PET)/montmorillonite (MMT) nanocomposites were prepared by solution intercalation method. The clay was organo-modified with intercalation agent of cetyltrimetylammonium chloride (CMC). XRD showed that the layers of MMT were intercalated by CMC. Four nanocomposites with organoclay contents of 1, 5, 10, and 15 wt% were prepared by solution blending. XRD showed that the interlayer spacing of organoclay in the nanocomposites depends on the amount of organoclay. The nucleating effect of organoclay is investigated using differential scanning calorimetry (DSC) analysis. Clay behaves as a nucleating agent and enhances the crystallization rate of PET. Maximum enhancement in crystallization rate for the nanocomposites was observed in blends containing ca. 10 wt% of clay in the range of 1–15 wt%. According to transmission electron microscopy (TEM), the organoclay particle was highly dispersed in the PET matrix without a large agglomeration of particles for low organoclay content (5 wt%). Agglomerated structure did form in the PET matrix at 15 wt% organoclay content.