低味环氧活性稀释剂

四川承华化工有限责任公司生产出低味环氧活性稀释剂，基本无异味，毒性低，遇明火不燃。用于调节环氧树脂的黏度，在胶粘剂中用量为10份（以100份环氧树脂计），几乎无不良气味释放，可制得无溶剂型环氧树脂胶粘剂和灌封胶，适用于电子、电器、机电、机械行业的粘接、灌封、浇注等。     

活性稀释剂含量对环氧树脂体系阻尼性能的影响

将活性稀释剂乙二醇二缩水甘油醚669加入Epon828/T403体系中,研究其对体系粘度及阻尼性能的影响。结果表明,669能显著降低双酚A型环氧树脂的粘度,改善其加工性能。随着669含量的增加,体系损耗峰的高度先升高后降低,而宽度持续增加,玻璃化转变温度明显降低。且当669质量分数为20%时,体系阻尼性能达到最优。此外,随着测试频率的增大,tanδ-T频向高温移动,tanδ峰值增大。     

活性稀释剂-环氧树脂体系性能研究

通过对比原材料在不同温度时的黏度变化,探讨了各原材料对温度的敏感性;然后分别采用3种固化剂系统研究了4种活性稀释剂-EP(环氧树脂)体系的热学性能、力学性能和变形性能。结果表明:温度对低黏度原材料初始黏度的影响远小于对高黏度原材料的影响;EP体系中引入单环氧基的活性稀释剂(AGE、BGE)或双环氧基的活性稀释剂(632)后,其活性稀释剂-EP体系的反应热降低,树脂适用期延长;三环氧基活性稀释剂(636)有利于加快EP体系的固化反应,这对快固型EP配方的设计具有重要意义;不同活性稀释剂-EP体系的密度大小趋势与力学强度趋势基本一致。     

活性稀释剂种类对环氧树脂体系性能的影响研究

采用丁基缩水甘油醚(660)、乙二醇二缩水甘油醚(669)和苯基缩水甘油醚(690)三种活性稀释剂对环氧树脂/甲基四氢邻苯二甲酸酐(MeTHPA)固化体系进行改性,研究了稀释剂对树脂胶液粘度及其固化物力学性能和电性能的影响。结果表明,当加入669和690稀释剂后,体系的介电性能基本不变,耐电弧性能提高,而660的加入会降低体系的介质损耗,对耐电弧性能影响很小。其中,当690的添加量为3%时,耐电弧达到94s,比纯树脂提高了22%;当添加量为3%～12%时,树脂固化物的拉伸强度稳定在45～55MPa之间。     

含氟活性稀释剂对环氧树脂流变性能的影响

为解决环氧树脂的高粘度给成型带来的困难,用NXS-11A型旋转粘度计研究了含氟活性稀释剂对环氧树脂体系的流变性能的影响。研究结果表明,含氟活性稀释剂/环氧树脂体系在常温(35℃)时为牛顿型流体;常温下,环氧树脂体系粘度随含氟活性稀释剂添加量的增加下降显著,当氟活性稀释剂添加6%时,其粘度约可下降50%;但温度较高时,粘度随含氟活性稀释剂添加量的增加下降缓慢。随着含氟活性稀释剂的增加,环氧树脂体系的流动活化能明显下降。     

活性稀释剂对环氧豆油丙烯酸酯光固化体系的影响

用环氧豆油与丙烯酸反应制备出环氧豆油丙烯酸酯预聚物,研究了活性稀释剂的组成、配比对紫外光固化速率、固化膜性能及施工性能的影响,并利用红外光谱对涂料光固化前后的结构进行了表征。结果表明:活性稀释剂的加入量以30%为宜,当其配比为10%苯乙烯,20%三羟甲基丙烷三丙烯酸酯时,光固化速率较快,固化膜无色透明,表面光滑平整,其硬度达到3H,且具有较好的柔韧性和附着力。     

活性稀释剂对环氧树脂阻尼性能的影响

研究了活性稀释剂RZ1021对环氧树脂黏度和阻尼性能的影响。黏度测试和动态力学热分析(DMA)表明,活性稀释剂能显著降低双酚A型环氧树脂的黏度;对环氧树脂阻尼损耗因子的峰值影响不大,只有较小幅度的波动;随活性稀释剂含量的增大,Tg大幅度降低;质量分数超过35%时,阻尼温域明显变宽并向低温移动;随DMA测试频率的增大,tanδ-T谱向高温移动。     

环氧活性稀释剂行业发展现状

介绍了目前国内外环氧活性稀释剂主要生产企业的产能、产量以及开工率等情况,分析了我国环氧活性稀释剂的消费量和消费结构,并对国内环氧活性稀释剂行业发展影响较大的部分风电产业政策作了汇总.     

环氧稀释剂十二烷基缩水甘油醚的合成

对稀释剂十二烷基缩水甘油醚的合成及影响产品质量的因素进行了研究,并以十二、十四混醇为原料进行了对比试验。     

TPP/PMMA复合物促进环氧树脂/酸酐体系的固化动力学研究

以三苯基膦(TPP)和甲基丙烯酸甲酯(MMA)为原料合成了TPP/PMMA复合物,用DSC研究了TPP/PMMA催化双酚A二缩水甘油醚(EP828)/甲基四氢苯酐(MTHPA)体系固化反应动力学。非等温固化动力学研究结果表明,转化率在20%～60%范围内,用Ozawa法能较好地描述环氧树脂/酸酐体系的固化反应过程。     

Cure kinetics of epoxy/anhydride nanocomposite systems with added reactive flame retardants

Montmorillonite nanocomposite systems obtained from epoxy cured using anhydride and the addition of a reacting flame retardant are studied in this paper. In particular, a thermokinetic analysis of the behavior of five different compounds was performed, using a differential scanning calorimeter. The isothermal tests showed double reaction peaks, due to the cure reactions of DGEBA/acid anhydride systems. The comparisons between dynamic thermograms (and between isothermal ones, too) for the different mixtures also showed that the addition of other active substances (such as a nanofiller or a flame retardant additive) does not change the mechanism of crosslinking from a qualitative point of view, but both the nanoreinforcement and the flame retardant seemed to exert an evident catalytic action on the cure reactions. A model describing the cure behavior of the aforementioned materials is proposed in this work. This model takes into account the fact that the reaction mechanism of each analyzed system is composed of a couple of parallel phenomena: the fast opening of anhydride ring (corresponding to a first exothermic peak and characterized by “n‐th order” kinetics) and resin networking (corresponding to a second exothermic peak and characterized by an “auto‐catalytic with zero initial velocity” behavior). The verification of the proposed model was performed by means of a comparison between experimental data (normalized curves derived from DSC thermograms) and theoretical data (derived from a numerical integration—using the second order Runge–Kutta method—of the model‐representative equation) and provided very good results. This allows one to apply such a model to any engineering process problem concerning the cure of DGEBA/acid anhydride/phyllosilicate nanocomposite systems. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1676–1689, 2004     

六氢苯酐／环氧树脂体系的固化工艺研究

研究了以双酚A环氧树脂为基体,六氢苯酐(HHPA)为固化剂,MZ-31为固化促进剂组成的六氢苯酐/环氧树脂体系。结合凝胶化实验、动态DSC法和红外跟踪实验法,并借助T-β图外推法,确定了HHPA/EP体系的最佳固化工艺为:100℃/1h 120℃/2h 150℃/4h,再于190℃下后处理3 h。     

环氧树脂/苯乙烯-马来酸酐共聚物体系固化动力学研究

用示差扫描量热仪(DSC)对环氧树脂/苯乙烯-马来酸酐共聚物/甲基咪唑体系的固化反应过程进行了分析,并用Kissinger和Ozawa方法分别求得固化反应的表观活化能ΔE为58.27 kJ/mol和64.93 kJ/mol;根据Crane理论计算得到该体系的固化反应级数n=0.85,为该环氧树脂体系的固化工艺确定提供理论依据。     

环氧树脂/酸酐增韧体系的性能研究

EP(环氧树脂)/酸酐体系固化后形成高度交联的3维网状结构,导致其性能较脆;在不影响大尺寸制件液体成型工艺的前提下,综合考虑成本和增韧效果,初步选定可与EP基体形成"海岛结构"的奇士增韧剂对上述固化体系进行改性。研究结果表明:当w(奇士增韧剂)=5%(相对于EP质量而言)时,EP/酸酐固化体系的增韧效果相对最好;此时EP/酸酐浇铸体的拉伸强度为85.6 MPa、弯曲强度为135.8 MPa、冲击强度为30.6 k J/m~2、断裂伸长率为5%且热变形温度(HDT)仅降低了6℃,说明适量的奇士增韧剂既可弥补传统液体橡胶增韧EP的不足,也可改善浇铸体的断裂韧性,同时不影响浇铸体的热稳定性。     

Curing kinetics and chemorheology of epoxy/anhydride system

The curing kinetics and chemorheology of a low‐viscosity laminating system, based on a bisphenol A epoxy resin, an anhydride curing agent, and a heterocyclic amine accelerator, are investigated. The curing kinetics are studied in both dynamic and isothermal conditions by means of differential scanning calorimetry. The steady shear and dynamic viscosity are measured throughout the epoxy/anhydride cure. The curing kinetics of the thermoset system is described by a modified Kamal kinetic model, accounting for the diffusion‐control effect. A chemorheological model that describes the system viscosity as a function of temperature and conversion is proposed. This model is a combination of the Williams–Landel–Ferry equation and a conversion term originally used by Castro and Macosko. A good agreement between the predicted and experimental results is obtained. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3012–3019, 2003     

低共熔点芳胺固化环氧树脂动力学研究

采用低熔点的间苯二胺(m-PDA)对新型固化剂长链柔性芳香胺(LCDA)进行物理共混改性,得到了1种低共熔点的芳胺环氧固化剂。n(m-PDA)∶n(LCDA)=1∶1时,混合物具有低共熔温度为50.9℃。研究了该低共熔点芳胺与环氧树脂(E-51)的固化行为,根据Melak方法和Kissinger方法确定了体系的固化动力学模型及固化动力学参数。结果表明:该体系的固化动力学模型符合n级固化反应方程,其表观活化能△E为54.49 kJ/mol,频率因子A为7.28×105和反应级数n为0.813。此外,运用外推法得体系起始固化温度Tgel为110℃,恒温固化温度Tcure为150℃,后处理温度Ttreat为185℃,还对体系的固化工艺进行了探讨。     

Influence of an epoxy reactive diluent on the thermal degradation process of the system DGEBA n = 0/1,2 DCH

The thermal degradation of two epoxy systems diglycidyl ether of bisphenol A (DGEBA n = 0)/1,2‐diamine cyclohexane (DCH) containing different concentrations of an epoxy reactive diluent, vinylcyclohexene dioxide (VCHD), was studied by thermogravimetric analysis to determine the reaction mechanism of the degradation process for these two systems. Values of the activation energy, necessary for this study, were calculated by using various integral and differential methods. Values obtained by using the different methods were compared to the value obtained by Kissinger's method, which does not require a knowledge of the reaction mechanism. All the experimental results were compared to master curves in the range of Doyle's approximation (20–35% of conversion). Analysis of the results suggests that the two reaction mechanisms are R_n and F_n deceleratory type in contrast with the sigmoidal A₂ type of the system with filler and the sigmoidal A₄ type of the system without additives. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1199–1207, 2004