The Preparation and PhysicoChemical Study of Glass,Jute and Hybrid Glass-Jute Bisphenol-C-Based Epoxy Resin Composites

Glass-PA (EC-G-PA), Jute-PA (EC-J-PA), Glass-Jute-Glass (EC-GJG-PA), Jute-Glass-Jute (EC-JGJ-PA) composites of epoxy resin of bisphenol-C (EBC) have been prepared using a hand lay-up technique at 150°C under 27.58 MPa pressure for 6 h by using phthalic anhydride as a curing agent. EC-G-PA, EC-J-PA EC-GJG-PA and EC-JGJ-PA Possess 34, 41, 27 and 21 MPa tensile strength; 34, 27, 19 and 22 MPa flexural strength; 1.9, 1.0, 1.6 and 1.3 kV/mm electric strength and 4.2 × 10¹³, 1.2 × 10⁹, 8.7 × 10¹¹ and 4.0 × 10¹¹ ohm.cm volume resistivity. Hydrolytic stability of the composites was tested against water, 10% aq. HCl and NaCl solutions at 35°C and also in boiling water. The percent water uptake, equilibrium time and diffusivity of the composites have been determined and discussed their possible applications.     

Preparation,Mechanical and Electrical Properties and Water Absorption Study of Novel Bisphenol-C-Formaldehyde-Acrylate Treated and Untreated Jute Composites

The depolarization current spectra for polyvinyledenefluoride (PVDF), poly methylmethacrylate (PMMA), and their double-layered samples have been recorded under different polarizing conditions. When double-layered sample is polarized at 323 K with high field, a new TSDC peak is observed that is inherent in PMMA and PVDF when considered individually. This is because of the trapping charge carriers at the PVDF–PMMA interface. The space charge peak is shifted toward the lower temperature side for the PMMA and PVDF samples; however, this trend of peak shifting was not found for double-layered samples. The trapping of charge carriers in the metal polymer interface is responsible for space charge peak. This trapping of charge carriers in polymer-polymer interface is interesting, and this process is responsible for interfacial polarization in double-layered samples.     

环氧树脂/氰酸酯树脂体系的改性研究

为增加环氧树脂/氰酸酯树脂体系(EP/CE)的韧性,向EP/CE树脂体系中引入第三组分——双酚A(BPA)。采用傅里叶转换红外光谱、差式扫描量热仪研究了BPA对EP/CE固化温度与固化机理的影响,测定了固化物的力学性能和耐湿热性。结果表明,BPA的加入改变了EP/CE树脂体系固化历程,引起EP/CE树脂体系固化温度明显下降。BPA在EP/CE树脂体系内可形成大量的—C—O—C—键,与EP/CE树脂体系形成互穿网络,提高了EP/CE的韧性。随着体系中BPA含量的增加,其力学性能提高,吸水率有所下降。当CE∶EP∶BPA质量比为7∶3∶0.75时,其拉伸强度提高27.3%,冲击强度提高34.7%,吸湿率降为1.2%。     

低成本高性能酚醛树脂基烧蚀材料的性能研究

本文对硼酚醛树脂、高残碳酚醛树脂、S-157酚醛树脂的固体含量、粘度、凝胶时间进行了表征和对比,此基础上对比研究了连续玄武岩纤维平纹布增强三种酚醛树脂复合材料的密度、硬度、导热系数,同时对三种复合材料的烧蚀性能和力学性能进行了测试和对比。研究结果表明：硼酚醛树脂复合材料的力学性能最好,S-157酚醛树脂复合材料其次,高残碳酚醛树脂复合材料的力学性能最差;在烧蚀性能方面,硼酚醛树脂复合材料和高残碳酚醛树脂复合材料相当,S-157酚醛树脂复合材料最差。     

新型酚醛树脂基耐烧蚀复合材料的性能研究

本文采用GPC和TG对高残碳酚醛树脂（HCYPR）和硼酚醛树脂（BPR）的分子量及其分布、热失重特性进行了表征和对比。同时对比了S-2GFC／HCYPR和S-2GFC／BPR的力学性能和烧蚀性能。研究结果发现：与HCYPR相比,BPR的分子量更小,分布宽度更窄,与增强体的浸润性更好;BPR的800℃残碳率高于HCYPR;S-2GFC／HCYPR的质量烧蚀率要大于S-2GFC／BPR,但线烧蚀率小于后者。S-2GFC／BPR比S-2GFC／HCYPR强度的提高百分数从59．4％到73．9％不等,其中压缩强度提高了73．9％;模量的提高百分数从27．5％到31．9％不等,其中弯曲模量提高了31．9％。     

球形二氧化硅/环氧树脂复合材料制备与性能表征

以普通角形二氧化硅为原料,采用氧-乙炔火焰法制备出球形二氧化硅。将环氧树脂(E-51)、固化剂(906)、固化促进剂(DMP-30)和球形化前后二氧化硅按照不同的比例经机械搅拌混合、超声分散和升温固化(100℃、2h和150℃、2h)后制备出二氧化硅/环氧树脂复合材料。研究对比球形化前后二氧化硅对环氧树脂浇注体系热学和力学性能的影响。结果表明:球形二氧化硅的加入,提高了环氧树脂的热稳定性,添加量30%时热分解温度达到最大值340℃,球形化后二氧化硅/环氧树脂复合材料热膨胀系数和初始黏度较球形化前明显降低,力学性能得到提高。     

聚丙烯/环氧树脂复合材料的制备及其性能研究

在聚丙烯(PP)基体中加入环氧树脂(EP)、固化剂、马来酸酐接枝聚丙烯(PP-g-MAH),通过动态固化制备了PP/EP复合材料,并对其相容性、力学性能、结晶性能等进行了研究。结果表明:PP/EP为不相容体系,PP-g-MAH作为反应性增容剂对体系的刚性和模量影响较大;通过EP和PP-g-MAH的接枝反应,增强了两相间的界面作用力,降低了EP分散相的尺寸,改善了PP/EP复合材料的力学性能。力学性能测试结果表明,EP与PP-g-MAH的最佳配比为1:1;等温结晶的偏光照片和DSC数据表明,EP阻碍了PP的结晶,使其球晶微细化、结晶度降低。     

介孔铈锆复合氧化物-环氧树脂杂化材料的制备与性能研究

利用表面活性剂模板法制备介孔铈锆复合氧化物,使用硅烷偶联剂KH570对介孔铈锆复合氧化物粒子进行改性,采用共混法制备出介孔铈锆复合氧化物-环氧树脂杂化材料,对杂化材料进行表征和分析,研究了介孔铈锆复合氧化物-环氧树脂杂化材料的力学性能、耐热性能并探讨其改善的机理。     

光敏性酚醛环氧树脂的合成及性能

合成了一种光敏性酚醛环氧树脂,研究了其合成工艺条件.用FTIR对合成的树脂的结构进行了表征,测试了合成树脂的光学活性、力学性能、耐溶剂性、耐酸碱性等.     

Moisture Absorption Behavior of Treated and Untreated Eggshell Particulate Epoxy Composites

Weight gain and thickness swelling in bio-waste composites material leads to an adverse effect on properties. In the present investigation the effect of different environments (saline, mineral, kerosene, subzero temperature) on the physical properties of the composites which are fabricated with unboiled(untreated) and boiled(treated 200 °C) eggshell filler materials are studied. XRD, SEM and ultimate analysis of the unboiled and boiled eggshells are also studied. The composites of different weight percentage 4, 8 and 12 wt% of unboiled and boiled eggshell filler epoxy composites are fabricated by a hand lay-up technique. The 12 wt% of boiled eggshell particulates reinforced epoxy composites showed the highest weight gains when exposed to different environments. Least absorption rate observed was for 4 wt% eggshell filler composite in subzero temperature condition. The composites showed a peculiar environmental behavior when exposed to kerosene.

     

环氧树脂改性PET的研究

选取环氧树脂(EP)作为改性剂,在双螺杆挤出机中对聚对苯二甲酸乙二醇酯(PET)进行熔融扩链。研究了EP含量对复合材料力学性能和结晶性能的影响,并用红外光谱法探究了反应机理。结果表明:随着EP含量的增加,复合材料的冲击强度和拉伸强度呈上升趋势;EP的加入促进了PET的成核能力,但结晶度随着EP含量的增加而下降。通过红外光谱可以明显看出:EP的加入生成了新的羟基。     

Preparation and Physico-Chemical Study of Sandwich Glass-Jute-Bisphenol-C-Formaldehyde Resin Composites

Glass-Jute-bisphenol-C-formaldehyde (Glass-Jute-BCF) sandwich composites were prepared by hand lay-up technique at 150°C under 30.4 MPa pressure for 2 h. The resin, glass and jute fiber content in the sandwich composite were 33.3, 10.4 and 56.3 wt%, respectively. 10 prepregs containing 8 inner prepregs of jute mats sandwiched between 2 outer prepregs of glass mats. Glass-Jute-BCF sandwich composite has 23 MPa tensile strength, 119 MPa flexural strength, 1.72 kV/mm electric strength and 1.25 × 10¹² ohm cm volume resistivity. Tensile strength and volume resistivity both decreased, while flexural strength and electrical strength both improved upon hybridization. Sandwich composite showed high diffusivity in water, 10% NaCl and 10% HCl solutions as compared to Glass-BCF composite. Equilibrium water absorption time is found to be 72 h in all 3 environments. Comparatively low diffusivity is observed due to silane treated glass fibers. No effect of boiling water is observed on stability of composite. Saturation time in boiling water reduced 18 times without any damage to the composite. Glass-Jute-BCF sandwich composite may be useful for low load bearing applications in construction, electrical and electronic industries as well as in harsh acidic and saline environments.     

Hybrid Polymer Networks of Epoxy Resin and Substituted Phenolic Novolacs

Hybrid polymer networks of diglycidyl ether of bisphenol (DGEBA) resin and phenolic novolac resins were prepared and tested for mechanical properties, hardness, and water absorption. The novolacs employed were based on each of phenol and substituted phenols such as p-cresol, t-butyl phenol, and cardanol. Cardanol is the main constituent of cashew nut shell liquid (CNSL), a renewable resource. Blends containing 10–15 wt% of novolac resin show substantial improvement in properties. These properties show a declining trend with higher novolac loading. The stoichiometric ratio between phenol and formaldehyde in the novolacs was optimized (1:0.8) for maximum property enhancement. The property profiles of the epoxy/novolac networks show that novolacs are effective modifiers for commercial epoxy resin. Incorporation of novolacs of substituted phenols results in relatively greater improvement in energy absorption during failure.     

碳纳米管/石墨烯杂化材料改性环氧树脂研究

采用物理法和化学多步法合成了碳纳米管/石墨烯杂化材料,通过红外光谱表征证明杂化材料的成功合成,通过沉淀实验表明化学多步法合成的碳杂化材料具有良好的分散性和分散稳定性。将碳纳米杂化材料按照质量分数0.3%添加到环氧树脂(EP)中制备复合材料,对复合材料的拉伸强度和断裂韧性进行表征,并通过扫描电子显微镜对复合材料的断面进行表征。结果表明,碳纳米管/石墨烯杂化材料对EP的增强增韧效果较好,尤其是化学多步法合成的杂化材料改性EP复合材料,其拉伸强度最大,曲线积分面积最大,弹性模量最小,韧性最好。这可能要归因于化学多步法合成的杂化材料具有更为稳定的三维结构,可以更好地承担和转移外部载荷。     

纳米Al2O3/环氧树脂复合材料的制备及性能

在原位法制备纳米复合材料时，要使纳米粒子在树脂中分散均匀，必须首先获得稳定的单体悬浮体系。基于这一原理，本文通过对纳米Al2O3表面改性即选择合适的分散剂，获得稳定的纳米Al2O3/丙酮悬浮液，然后将环氧树脂溶解于其中，制得纳米Al2O3／环氧树脂复合材料。运用透射电子显微镜，观察了纳米Al2O3在环氧基体中的分散情况。分析并讨论了纳米Al2O3含量对该复合材料力学性能的影响。结果表明：利用稳定的悬浮体系能制得分散较为均匀的纳米复合材料，在纳米Al2O3含量为5％的情况下，纳米复合材料的力学性能达到最优。     

木质纤维增强环氧树脂复合材料的制备及性能研究(摘要)

<正>天然植物纤维增强环氧树脂复合材料具有低成本、低能耗、环境友好等优良特性,近年来成为国内外研究热点,受到广泛关注。然而,天然植物纤维存在易吸湿、与基体树脂相容性差等缺点,在复合材料中的应用受到限制。本研究以木材剩余物杨木枝桠材为原料,通过机械粉碎法及化学机械浆法制备了杨木粉、杨木纤维;分别采用桐马酸酐甲酯、异氰酸酯/硅烷偶联剂和长链不饱和脂肪酸对杨木粉及杨木纤维表面改性,经热压成型制备了木质纤维增强环氧树脂复合材料。改性木质纤维表面疏水性高,与环氧树脂具有良好的界面相容性;制备的木质纤维增强环氧树脂复合材料,性能与     

环氧液晶/酚醛树脂复合材料的摩擦磨损性能研究

利用自行合成的端基为环氧基的热致性环氧液晶(LCE)与酚醛树脂(PF)通过熔融挤出进行原位复合制备了LCE/PF复合材料。研究了LCE含量对LCE/PF复合材料力学性能、硬度及摩擦性能的影响,使用扫描电子显微镜(SEM)观察了复合材料的磨损面形貌,分析了复合材料的摩擦磨损机理。研究结果表明:LCE含量为2.5%时,摩擦系数比未加LCE的稳定,力学性能也有所提高;在各温度下,LCE含量为7.5%的复合材料的体积磨损率比未加LCE的复合材料的小达,到了GB 5763—2008的要求。     

含三聚氰胺有机硅杂化物的环氧树脂性能研究

利用羟甲基化三聚氰胺和γ-环氧丙氧基三甲氧基硅烷反应制备了三聚氰胺有机硅杂化物,并用FTIR、29S iNMR对其结构进行了表征。然后将其与环氧树脂共混固化,对固化物热性能、阻燃性、力学性能进行了分析。结果表明,该三聚氰胺有机硅杂化环氧树脂固化物不仅保持纯环氧树脂玻璃化转变温度,而且在空气和氮气中的热失重分析显示,高温区域的热稳定性及残碳率比纯环氧树脂高;三聚氰胺有机硅杂化环氧树脂固化物的极限氧指数达到30.2,与纯环氧树脂相比,该固化物的极限氧指数提高了43%左右,抗冲击强度有较大幅度的提高,当三聚氰胺有机硅杂化物的添加量为环氧树脂质量的5%时,环氧树脂固化物的抗冲击强度达到20.3 kJ/mol;扫描电子显微镜照片显示三聚氰胺有机硅杂化环氧树脂的韧性较纯环氧树脂有很大提高。     

竹纤维增强环氧树脂复合材料的力学性能研究

采用硅烷偶联剂对竹纤维进行表面改姓,通过热压成型工艺制备了竹纤维增强环氧树脂(EP)复合材料。研究了竹纤维(BF)的长度、竹纤维含量和CaCO3含量对竹纤维/环氧(BF/EP)复合材料力学性能的影响。结果表明,竹纤维增强环氧复合材料,拉伸和冲击强度得到明显改善;当竹纤维含量为20%时,BF/EP复合材料的力学性能最佳,拉伸和冲击强度分别达到37.64MPa、8.30MPa。     

马来酸酐接枝聚丙烯纤维的结构和性能研究

采用熔融纺丝法制备了马来酸酐(MAH)接枝聚丙烯纤维,考察了接枝纤维的力学性能和吸湿率以及马来酸酐的残留量。结果表明,马来酸酐接枝聚丙烯纤维的断裂强度比纯聚丙烯纤维的低,接枝率越高强度越低,断裂伸长率则相反;随着接枝率的增加,纤维的取向度也逐渐升高。与聚丙烯纤维相比,接枝聚丙烯纤维的吸湿率有了明显提高,在相同拉伸倍数下提高了3-5倍;MAH残留量相当于接枝率(0.73％)的3.7％,表明主要是接枝的马来酸酐改变了聚丙烯纤维的性质。