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.     

环氧树脂低温机械性能的研究

研究了不同增韧剂对环氧树脂低温机械性能的影响。得出高腈含量的CTBN能全面提高环氧树脂低温机械性能的结论。     

橡胶增韧环氧树脂低温韧性的研究

以低分子量聚酰胺(PA300)为固化剂,以液体端羧基丁腈橡胶(CTBN)为增韧剂增韧改性双酚A型环氧树脂,考察了橡胶增韧剂、固化剂、稀释剂和无机填料对环氧树脂低温韧性的影响。通过对增韧体系应力应变特性和动态力学性能的研究表明,该体系具有优异的低温韧性。     

双酚A及端羧基丁腈橡胶对环氧树脂的增韧作用

以2-乙基-4-甲基咪唑为固化剂,分别以端羧基丁腈橡胶(CTBN)、CTBN/双酚A(BPA)或BPA为增韧剂增韧环氧树脂,研究了环氧树脂增韧体系的微观形貌和力学性能,考察了不同混料方式对CTBN增韧环氧树脂性能的影响。结果表明:CTBN增韧环氧树脂能使其固化物的冲击韧性有所提高,但其他力学性能降低;采用环氧树脂先与其进行预聚反应再经固化剂固化的方法能提高CTBN对环氧树脂的增韧效果;用CTBN/BPA为增韧剂不仅可以大幅度提高材料的冲击强度和扯断伸长率,而且可以提高弯曲强度与模量,克服了CTBN单一增韧导致材料强度下降的不足。BPA的加入可使环氧树脂固化物体系的弯曲强度、冲击强度和扯断伸长率有较大幅度的提高。     

液体端羧基丁腈橡胶增韧环氧树脂作为结构材料的研究(第一报)

本文介绍了液体端羧基丁腈橡胶CTBN增韧环氧树脂作为结构材料使用时,CTBN的丙烯腈(AN)含量和CTBN用量对增韧效果影响的系统研究。以六氢吡啶为固化剂的环氧树脂增韧体系,CTBN的AN含量最佳范围为23～30%,CTBN的最佳用量为10phr(每百份树脂的重量份数)。本文还讨论了CTBN分子量对增韧效果的影响以及影响相分离的各种因素。     

橡胶弹性体增韧环氧树脂的结构与性能研究

通过示差扫描量热仪、力学性能测试及电镜分析等研究了端羧基丁腈橡胶(CTBN)和核壳橡胶(CSR)增韧改性环氧树脂(EP)体系的结构与增韧改性效果,结果表明:CTBN和CSR都能显著提高环氧树脂的冲击强度,CSR增韧环氧体系的拉伸强度及弯曲强度增幅较大。CTBN的加入使环氧树脂的玻璃化温度大幅下降,EP/CSR体系的Tg也有所降低,但随CSR含量的增加又有回升的趋势。CTBN的加入对环氧体系的固化起到了抑制作用,体系的凝胶化时间明显变长;而CSR的加入对环氧体系的固化影响不大。比较而言,CSR增韧环氧体系的综合性能更佳。     

羧基液体丁腈橡胶增韧改性环氧树脂研究

用羧基液体丁腈橡胶（CTBN）对环氧树脂（EP）进行改性,合成CTBN/EP预聚物。通过研究不同配比CTBN/EP体系的性能,确定CTBN对EP的增韧效果。     

环氧树脂/CTBN复合材料的力学性能

采用端羧基液体丁腈橡胶(CTBN)对环氧树脂增韧改性,通过扫描电子显微镜观察了环氧树脂/CTBN复合材料的相态形貌,分析了增韧机理,测试了复合材料的力学性能。CTBN对环氧树脂的增韧机理是剪切变形与"钉扎"机制共同作用的结果;当CTBN添加量为15phr时,环氧树脂/CTBN的综合性能最佳,剪切强度、拉伸强度、悬臂梁缺口冲击强度分别为16.8MPa,28.4MPa,17.53kJ/m2;CTBN可与环氧树脂反应并嵌入其中,与环氧树脂随着固化反应的进行形成两相结构。     

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。     

端羧基液体丁腈橡胶改性TDE-85环氧树脂的性能

通过合成含端羧基液体丁腈橡胶(CTBN)嵌段的环氧树脂预聚物,再加入固化剂的方法制备了CTBN增韧改性TDE-85型环氧树脂复合材料,研究了该复合材料的固化特性及CTBN含量对其力学性能的影响,并用扫描电子显微镜观察了增韧的效果。结果表明,在CTBN/TDE-85复合材料中的CTBN质量分数为15%、以咪唑作为固化剂且固化温度为(100±1)℃的条件下,所制备CTBN/TDE-85复合材料的性能较好     

Mechanical and Dielectric Properties of NiZn Ferrite Powders-CTBN Modified Epoxy Resin Coatings

In this study, the effects of carboxyl terminated butadiene-acrylonitrile liquid rubber (CTBN) addition on the mechanical and dielectric properties of NiZn ferrite powders-CTBN modified epoxy resin coatings were investigated. It was observed that the occurrence of the small, dispersed spherical CTBN domains in the epoxy resin resulted from the phase separation between epoxy and CTBN could enhance the toughness and dielectric constant at low frequency due to the increase in the phase boundary between ferrite powders and epoxy resin for the samples modified with proper CTBN. The addition of ferrite powders can effectively improve the thermal stability of epoxy resin.     

环氧树脂及其改性树脂的低温性能分析和增韧研究(Ⅰ):低温性能分析

对环氧树脂及其改性后树脂的低温性能、动态性能进行了试验研究 ,得到环氧树脂及其增韧树脂在低温情况下材料特性 ;并对材料的断口照片进行了分析 ,得出在低温、低载荷作用下的橡胶增韧双酚A改性的环氧树脂共混体系中 ,共混体性能此时以橡胶颗粒的性能作为主导性能出现。     

一种高温固化环氧基体树脂的研制

采用预聚合、B阶树脂合成及机械共混工艺制备了一种高温固化环氧基体树脂,探讨了增韧剂-端羧基液体橡胶(CTBN)用量对基体树脂韧性和耐热性的影响.试验结果表明:当CTBN的用量为5phr,且与环氧树脂采用预聚合方式制得的基体树脂获得了较高的耐热性和韧性,玻璃化转变温度为189℃,冲击强度达到了26.12k J/m2;制得...     

Toughening of dicyandiamide-cured DGEBA-based epoxy resins by CTBN liquid rubber

Toughening of a diglycidyl ether of bisphenol-A (DGEBA)-based epoxy resin with liquid carboxyl-terminated butadiene acrylonitrile (CTBN) copolymer has been investigated. For this purpose six blend samples were prepared by mixing DGEBA with different concentrations of CTBN from 0 to 25 phr with an increment of 5 phr. The samples were cured with dicyandiamide curing agent accelerated by Monuron. The reactions between oxirane groups of DGEBA and carboxyl groups of CTBN were followed by Fourier-transform infrared (FTIR) spectroscopy. Tensile, impact, fracture toughness and dynamic mechanical analysis of neat as well as the modified epoxies have been studied to observe the effect of CTBN modification. The tensile strength of the blend systems increased by 26 % when 5 phr CTBN was added, and it remained almost unchanged up to 15 phr of CTBN. The elongation-at-break and Izod notched impact strength increased significantly, whereas tensile modulus decreased gradually upon the addition of CTBN. The maximum toughness of the prepared samples was achieved at optimum concentration of 15 phr of CTBN, whereas the fracture toughness (K _IC) remained stable for all blend compositions of more than 10 phr of CTBN. The glass transition temperature (T _g) of the epoxy resin significantly increased (11.3 °C) upon the inclusion of 25 phr of CTBN. Fractured surfaces of tensile test samples have been studied by scanning electron microscopic analysis. This latter test showed a two-phase morphology where the rubber particles were distributed in the epoxy resin with a tendency towards co-continuous phase upon the inclusion of 25 phr of CTBN.     

Mechanical and tribological properties of epoxy modified by liquid carboxyl terminated poly(butadiene-co-acrylonitrile) rubber

Diglycidyl ether of bisphenol A (DGEBA)-based epoxy resin was modified using liquid carboxyl-terminated poly(butadiene-co-acrylonitrile) (CTBN) rubber. The liquid CTBN contents used ranged from 2.5 to 20 parts per hundred parts of resin (phr). Mechanical properties of the modified resins were evaluated and the microstructures of the fracture surfaces were examined using SEM technique. The changes in storage modulus and the glass transition temperature were also evaluated using dynamic mechanical analysis (DMA). The tribological tests were performed using a ball-on-disc tribometer. The worn surfaces and the ball counter-mates after tribological tests were investigated using optical microscope technique. The results revealed the influence of liquid CTBN content on mechanical and tribological properties, and also microstructure of the modified epoxy resins. Impact resistance increased whereas the storage modulus and the hardness decreased when the CTBN rubber was introduced to the epoxy network. The coefficient of friction of the CTBN-modified epoxy was lower than that of the neat epoxy. The CTBN content of lower than 10 phr was recommended for improving the wear resistance of epoxy resin. Changes in tribological properties of the CTBN-modified epoxy correspond well to those in mechanical changes, especially the toughness properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synergistic toughening of epoxy resin by CTBN and CM-β-CD

Carboxymethyl-β-cyclodextrin (CM-β-CD) and carboxyl terminated liquid nitrile rubber (CTBN) were used as binary component fillers in toughening the epoxy resin (E-54). For a single component filler system, the addition of CTBN resulted in significantly improved fracture toughness but reduction of glass transition temperature (T_g) and modulus of epoxy resin. On the other hand, the addition of CM-β-CD resulted in a modest increase in modulus and T_g, and significant improvement in toughness. This work provides a promising route of nanocomposites with excellent toughness. Besides the mechanism of synergistic toughening in this project was explained, and the major toughening mechanisms were attributed to interfacial micro-cracks, energy dissipation of CM-β- CD. This work gives us a further understanding of the modification effect of β- CD.     

Thermal stability and kinetics analysis of rubber‐modified epoxy resin by high‐resolution thermogravimetric analysis

A dynamic heating rate mode of high‐resolution thermogravimetric analysis was used to study the thermal and thermal‐oxidative stability, as well as kinetics analyses, of a model liquid rubber‐modified epoxy resin, Ep/CTBN, made up of bisphenol A diglycidyl ether‐based epoxy and carboxyl‐terminated butadiene acrylonitrile rubber (CTBN). Results show that the thermal degradation of Ep/CTBN resin in nitrogen and air consists of two and three independent steps, respectively. Moreover, Ep/CTBN has a higher initial degradation temperature and higher activation energy than those of pure epoxy resin in both gases, indicating that the addition of CTBN to epoxy can improve the thermal and thermal‐oxidative stability of pristine epoxy resin. Kinetic parameters such as activation energy, reaction order, and preexponential factor of each degradation step of both Ep/CTBN and pure epoxy resins in air and nitrogen were calculated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3594–3600, 2003     

端羧基液体丁腈橡胶改性环氧结构胶的研究

采用端羧基液体丁腈橡胶(CTBN)增韧环氧树脂,制备了双组分室温固化环氧结构胶。利用傅里叶变换红外光谱仪(FTIR)、微机控制万能材料试验机及扫描电镜(SEM)对固化过程、固化产物剪切强度及固化产物微观形态进行了表征。该胶树脂甲组分的最佳制备条件如下:环氧树脂与CTBN的质量比8∶1,反应温度200℃,保温时间2.5 h。该胶在室温下固化24 h,室温剪切强度可达29.24 MPa,耐介质性能良好,CTBN改性环氧树脂增韧效果显著。