环氧树脂体系固化反应及其复合材料介电性能

环氧树脂是一类综合性能优异的热固性高分子材料，作为胶粘剂、复合材料用树脂基体、涂料等形式广泛应用于电子电气、机械制造、化工防腐、航空航天等众多领域中，成为各工业领域中不可缺少的基础材料。本文综述了本研究室在咪唑／环氧树脂体系，稀土有机化合物、叔胺羧酸复盐／酸酐／环氧树脂体系，氰酸酯／环氧树脂体系，硼胺络合物／环氧树脂体系的固化反应机理、固化反应动力学及其固化物结构与性能关系，纤维含量、排列方向、偶联剂种类等对玻璃纤维增强环氧树脂基复合材料及其界面介电性能的影响等6个方面的研究进展。     

聚甲基二间苯二乙炔基硅烷改性二氧化双环戊二烯环氧树脂及其复合材料的性能

用聚甲基二间苯二乙炔基硅烷树脂（PSA）改性二氧化双环戊二烯（R-122环氧树脂）得到R-122/PSA树脂体系,并以该树脂为基体制备了玻璃纤维复合材料。通过FT-IR、DSC和TGA研究了R-122/PSA树脂的固化反应及其耐热性能,同时研究了R-122/PSA基复合材料的力学性能、耐热性能、介电性能和耐水性能。结果表明：改性树脂在高温下保持了良好的耐热性能,mPSA/mR-122=0.2的固化物在800°C下质量保留率比纯R-122树脂的提高了30%。所制备的复合材料常温下弯曲强度达到735 MPa,220°C下的弯曲强度达到418.4 MPa,不仅保留了良好的力学性能,而且耐热性能得到了很好的提升,同时其浸泡96 h后的吸水率仅为0.65%,耐水性能优异。     

聚苯乙炔基苯基硅氧硼烷树脂及其复合材料的性能

将双(N-间乙炔基苯基邻苯二甲酰亚胺)醚(DAIE)和双酚A型氰酸酯(CE)分别加到聚苯乙炔基苯基硅氧硼烷(PSOB)和三苯乙炔基苯基硅烷(PTPES)混合体系中进行改性,制得两种纤维增强复合材料PSOB-PTPES-DAIE和PSOB-PTPES-CE.研究了固化后树脂的热稳定性能、力学性能、介电性能和耐水性能.结果...     

噁唑烷酮环氧树脂的研究进展

含噁唑烷酮结构的树脂具有优良的耐热性、电性能及物理机械性能等。将噁唑烷酮环引入环氧树脂,可提高固化物的玻璃化转变温度、粘结性、介电性和阻燃性等。本文综述了噁唑烷酮环氧树脂的一般合成方法,探讨了原料配比、反应温度、催化剂种类及用量对噁唑烷酮环氧树脂合成过程的影响,分析了固化剂与噁唑烷酮环氧树脂固化产物性能之间的联系,对噁唑烷酮环氧树脂在绝缘材料、涂料、粘合剂、印刷电路板以及高性能树脂基体等领域的应用情况进行了详细介绍,并对其发展前景予以展望。     

苯并噁嗪改性液体成型环氧树脂的研究

采用具有低固化收缩特性的苯并噁嗪树脂(benzoxazine,BOZ)对液体成型环氧树脂进行改性,以期在不改变液体成型树脂耐热性、工艺性及力学性能的前提下,大幅度降低树脂的固化收缩率.对比研究了不同BOZ含量改性树脂的固化收缩特性、固化反应特性、液体成型工艺性及力学性能.并采用真空辅助树脂浸渗(vacuum assisted resin infusion,VARI)工艺制备了单向碳纤维织物增强复合材料,研究了复合材料的力学性能.结果表明,加入BOZ对液体成型树脂的反应性、工艺性及耐热性影响不大,改性树脂的固化收缩随BOZ含量的提高逐渐减小,其中BOZ质量分数为15 wt%的改性树脂,较未改性树脂的固化收缩减小约80%,拉伸强度提高约19%,冲击强度提高约148%.以此改性树脂作为基体的复合材料相对于未改性树脂复合材料的拉伸强度提高约23%,层间剪切强度提高约9%,具有良好的力学性能和界面结合性能.     

偶联剂对玻璃纤维/环氧树脂基复合材料介电性能的影响

偶联剂对玻璃纤维／环氧树脂基复合材料介电性能的影响陈平刘胜平张明艳（哈尔滨理工大学电工材料系哈尔滨１５００４０）关键词环氧树脂基复合材料，介电性能，偶联剂，浸润性玻璃纤维／环氧树脂基复合材料（ＧＦＲＰ）具有优异的电气和力学性能．然而孔隙的存在强烈地...     

耐高温可溶性聚酰亚胺树脂及其复合材料

制备了2种耐高温可溶型聚酰亚胺树脂(PI-1, PI-2)及其复合材料, 系统研究了树脂的工艺性, 纯树脂固化物的热性能及其复合材料的界面形貌、 介电性能和力学性能. 研究结果表明, 树脂低聚物在极性非质子溶剂中具有良好的溶解性, 且熔体黏度较低, 表明其具有优异的加工性能. 两种树脂固化物在空气中的5%热失重温度均高于550 ℃, PI-1树脂的玻璃化转变温度(T_g)为430 ℃, PI-2树脂的T_g为380 ℃. 石英纤维/PI-1和石英纤维/PI-2复合材料具有较低的介电常数和介电损耗. 碳纤维/PI-1复合材料在420 ℃下的弯曲强度保持率可达62%, 层间剪切强度保持率可达48%, 具有较优异的高温力学性能. 采用普通模压工艺制备了厚度高达45 mm的复合材料制件, 进一步证明这2种树脂具有优异的工艺性.     

动态固化聚丙烯/环氧树脂共混物的研究

将动态硫化技术应用于热塑性树脂 热固性树脂体系 ,制备了动态固化聚丙烯 (PP) 环氧树脂共混物 .研究了动态固化PP 环氧树脂共混物中两组分的相容性、力学性能、热性能和动态力学性能 .实验结果表明 ,马来酸酐接枝的聚丙烯 (PP g MAH)作为PP和环氧树脂体系的增容剂 ,使分散相环氧树脂颗粒变细 ,增加了两组分的界面作用力 ,改善了共混物的力学性能 .与PP相比 ,动态固化PP 环氧树脂共混物具有较高的强度和模量 ,含 5 %环氧树脂的共混物拉伸强度和弯曲模量分别提高了 30 %和 5 0 % ,冲击强度增加了 15 % ,但断裂伸长率却明显降低 .继续增加环氧树脂的含量 ,共混物的拉伸强度和弯曲模量增加缓慢 ,冲击强度无明显变化 ,断裂伸长率进一步降低 .动态力学性能分析 (DMTA)表明动态固化PP 环氧树脂共混物是两相结构 ,具有较高的储能模量 (E′)     

DAIP树脂及其复合材料的性能研究

加入热固性丁苯树脂可降低DAIP树脂的酯键密度,提高其耐水性,在该体系中加入适量的偶联剂,可改善树脂与玻璃纤维的界面,提高复合材料的耐水性和介电性能。     

硅炔杂化树脂改性有机硅树脂及其复合材料的性能

用一种硅炔杂化树脂聚（甲基硅烷-二乙炔基苯）（PSP）改性有机硅树脂（HS）,通过FT—IR和TGA研究了树脂体系的固化反应及耐热性,并对制备的复合材料进行力学性能、耐热性能和介电性能研究。结果表明：当HS与PSP的质量比为5：5时综合性能最优,树脂体系在氮气氛围下质量损失5％时的温度（T幽）为691℃,1000℃时质量保留率为88％;HS—PSP树脂短切玻纤复合材料冲击强度为21kJ／m^2,弯曲强度为65MPa,200℃时的弯曲强度高温保留率为78％,介电常数为4．6,介电损耗因数为7．9×10,体积电阻为6．7×10^13Ω。改性后的复合材料具有优异的力学、耐热和介电性能。     

环氧树脂与氰酸酯共固化反应的研究

应用DSC、FT IR对乙酰丙酮过渡金属络合物催化促进的环氧树酯与氰酸酯共固化反应行为、历程以及固化物的结构特征进行了研究探讨 .结果表明 ,促进剂能够明显的降低固化反应温度 ,缩短固化反应时间 .反应历程首先是氰酸酯发生自聚反应形成二聚体或三聚体 (三嗪环 ) ,然后二聚体可进一步共聚形成三嗪环 ,此过程伴随着环氧基的聚醚反应 ,最后是三嗪环与剩余的环氧基反应形成唑烷酮 .在氰酸酯欠量的条件下 ,固化树脂中主要是唑烷酮和聚醚结构 ,三嗪环结构很少 ;在氰酸脂适量或过量条件下 ,固化树脂主要是三嗪环和唑烷酮结构 ,聚醚结构很少 .     

Thermal and physical properties of flame-retardant epoxy resins containing 2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)-1,4-naphthalenediol and cured with dicyanate ester

2-(6-oxido-6H-dibenz(c,e)(1,2)oxaphosphorin-6-yl)-1,4-naphthalenediol (DOPONQ) was prepared by the addition reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) with 1,4-naphthoquinone. The phosphorus-containing diol (DOPONQ) was used as a reactive flame retardant by an advancement reaction with the diglycidyl ether of bisphenol-A epoxy (DGEBA) resin at various stoichiometric ratios. DOPONQ-containing advanced epoxy was separately cured with various dicyanate esters to form flame-retardant epoxy/cyanate ester systems. The effect of the phosphorus content and dicyanate ester structure on the curing characteristic, glass transition temperature, dimensional stability, thermal stability, flame retardancy, and dielectric property was studied and compared with that of the control advanced bisphenol-A epoxy system. The DOPONQ-containing epoxy/cyanate ester systems exhibited higher glass transition temperatures as well as better thermal dimensional and thermal degradation stabilities. The flame retardancy of the phosphorus-containing epoxy/dicyanate ester system increased with the phosphorus content, and a UL-94 V-0 rating could be achieved with a phosphorus content as low as 2.1%.     

Studies on thermal and morphological properties of 1,1-bis(3-methyl-4-cyanatophenyl)cyclohexane-epoxy-bismaleimide matrices

A new cyanate ester monomer, 1,1-bis(3-methyl-4-cyanatophenyl)cyclohexane has been synthesized and characterized. Epoxy modified with 4, 8 and 12% (by weight) of cyanate ester were made using epoxy resin and 1,1-bis(3-methyl-4-cyanatophenyl)cyclohexane and cured by using diaminodiphenylmethane. The cyanate ester modified epoxy matrix systems were further modified with 4, 8 and 12% (by weight) of bismaleimide (N,N′-bismaleimido-4,4′-diphenylmethane). The formation of oxazolidinone and isocyanurate during cure reaction of epoxy and cyanate ester blend was confirmed by IR spectral studies. Bismaleimide-cyanate ester-epoxy matrices were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and heat deflection temperature (HDT) analysis. Thermal studies indicate that the introduction of cyanate ester into epoxy resin improves the thermal degradation studies at the expense of glass transition temperature. Whereas the incorporation of bismaleimide into epoxy resin enhances the thermal properties according to its percentage content. However, the introduction of both cyanate ester and bismaleimide influences the thermal properties according to their percentage content. DSC thermogram of cyanate ester modified epoxy and bismaleimide modified epoxy show unimodel reaction exotherms. The thermal degradation temperature and heat distortion temperature of the cured bismaleimide modified epoxy and cyanate ester-epoxy systems increased with increasing bismaleimide content. The morphology of the bismaleimide modified epoxy and cyanate ester-epoxy systems were also studied by scanning electron microscopy. Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis and properties of a cyanate ester containing dicyclopentadiene(II)

A 2,6‐dimethyl phenol‐dicyclopentadiene novolac (DCPDNO) was synthesized from dicyclopentadiene and 2,6‐dimethyl phenol, and the resultant DCPDNO was reacted with cyanogen bromide into 2,6‐dimethyl phenol‐dicyclopentadiene cyanate ester (DCPDCY). The structures of the novolac and cyanate ester were confirmed with Fourier transform infrared spectroscopy, elemental analysis, mass spectrometry (MS), and nuclear magnetic resonance. For the purpose of increasing the mobility of residual DCPDCY during the final stage of curing and achieving a complete reaction of cyanate groups, a small quantity of a monofunctional cyanate ester, 4‐tert‐butylphenol cyanate ester (4TPCY), was added to DCPDCY to form the cyanate ester copolymer. The synthesized DCPDCY was then cured with 4TPCY at various molar ratios. The thermal properties of the cured cyanate ester resins were studied with dynamic mechanical analysis, dielectric analysis, and thermogravimetric analysis. These data were compared with those of the commercial bisphenol A cyanate ester system. Compared with the bisphenol A cyanate ester system, the cured DCPDCY resins exhibited lower dielectric constants (2.52–2.67 at 1 GHz), dissipation factors (0.0054–0.0087 at 1 GHz), glass‐transition temperatures (261–273 °C), thermal stability (5% degradation temperature at 406–450 °C), thermal expansion coefficients (4.8–5.78 × 10^?5/°C before the glass‐transition temperature), and moisture absorption (0.8–1.1%). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 671–681, 2005     

Preparation and characterization of bismaleimide/1,3-dicyanatobenzene modified epoxy intercrosslinked matrices

An intercrosslinked network of cyanate ester (CE)-bismaleimide (BMI) modified epoxy matrix system was made by using epoxy resin, 1,3-dicyanatobenzene and bismaleimide (N,N^′-bismaleimido-4,4^′-diphenyl methane) with diaminodiphenylmethane as curing agent. BMI-CE-epoxy matrices were characterised using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and heat deflection temperature (HDT) analysis. The matrices, in the form of castings, were characterised for their mechanical properties such as tensile strength, flexural strength and unnotched Izod impact test as per ASTM methods. Mechanical studies indicated that the introduction of cyanate ester into epoxy resin improves the toughness and flexural strength with reduction in tensile strength and glass transition temperature, whereas the incorporation of bismaleimide into epoxy resin influences the mechanical and thermal properties according to its percentage content. DSC thermograms of cyanate ester as well as BMI modified epoxy resin show an unimodal reaction exotherm. Electrical properties were studied as per ASTM method and the morphology of the BMI modified epoxy and CE-epoxy systems were studied by scanning electron microscope.     

Viscoelastic properties and morphology of dicyanate ester/epoxy co-polymers modified with polysiloxane and butadiene–acrylonitrile rubbers

Dynamic mechanical analysis was conducted on specimens prepared from cyanate ester (CE) and epoxy (EP) resins cured together at various mass compositions. Increase of amount of epoxy resin in composition was shown to have a disadvantageous effect on glass transition temperature (T _g). It was shown that post-curing procedure was needed to produce a polymer matrix with a single glass transition relaxation, but increase in post-cure temperature up to 250 °C resulted in slight reduction in T _g for epoxy/cyanate copolymers. TG results proved that the presence of epoxy resin reduces thermal stability of the cyanate/epoxy materials. The neat CE and EP/CE systems containing 30 wt% of epoxy resin were modified using epoxy-terminated butadiene–acrylonitrile rubber (ETBN) and polysiloxane core–shell elastomer (PS). The scanning electron microscopy (SEM) results showed the existence of second phase of ETBN and PS modifiers. Only in the case of EP/CE composition modified with ETBN, well-dispersed second phase domains were observed. Analysis of SEM images for other CE- and EP/CE-modified systems revealed the formation of spherical aggregates.     

Synthesis and characterization of P/Si flame retardant and its application in epoxy systems

In this report, a novel phosphorus/silicon‐containing reactive flame retardant, hexa(3‐triglycidyloxysilylpropyl)triphosphazene (HGPP), was synthesized and characterized by Fourier transform infrared spectrometry and nuclear magnetic resonance spectra (¹H, ³¹P, and ²⁹Si), respectively. To prepare cured epoxy, HGPP had been co‐cured with diglycidyl ether of bisphenol‐A (DGEBA) via 4,4‐diaminodiphenylsulfone as a curing agent. The mechanical, thermal, and flame retardant properties of the cured epoxy were evaluated by dynamic mechanical analysis, thermogravimetric analysis, and limiting oxygen index (LOI). According to these results, it could be found that incorporation of HGPP in the cured epoxy system showed good thermal stability, high LOI values, and high char yield at high temperature. As moderate loading of HGPP in the epoxy system, its storage modulus and glass transition temperature were higher than those of neat DGEBA. Copyright © 2011 John Wiley & Sons, Ltd.     

电子束辐射固化环氧树脂的动态力学分析——树脂化学结构、分子量及其分布的影响

应用不同化学结构、分子量及其分布的环氧树脂进行了电子束辐射固化实验 ,对固化物进行了动态力学分析 ,研究了不同样品凝胶含量、内耗tanδ及动态模量的变化规律 .分析结果表明环氧树脂辐射反应活性与其化学结构有很大关系 ,酚醛型环氧树脂的辐射反应活性高 ,固化后高温模量及玻璃化温度较高 ,而脂环族环氧树脂反应活性小 .在低辐射剂量下 ,环氧树脂的固化度随分子量增大略有下降 ,但固化物的玻璃化温度随分子量增加而升高 .增大辐射剂量 ,树脂固化度的提高受分子量大小的影响很小 ,分子量较大样品的网络均匀程度有所提高 ,在较高反应程度下 ,玻璃化温度主要受固化度影响 .树脂固化程度也是决定其模量高低的主要因素 ,而在固化程度相近的情况下 ,分子量的影响作用很大 .在同样辐射剂量下 ,分子量分布宽的树脂固化反应程度高 ,但交联网络均匀性低 .     

Mechanical,thermal and morphological behavior of bismaleimide modified polyurethane‐epoxy IPN matrices

An intercrosslinked network of bismaleimide modified polyurethane‐epoxy systems were prepared from the bismaleimide having ester linkages, polyurethane modified epoxy and cured in the presence of 4,4′‐diaminodiphenylmethane. Infrared spectral analysis was used to confirm the grafting of polyurethane into the epoxy skeleton. The prepared matrices were characterized by mechanical, thermal and morphological studies. The results obtained from the mechanical and thermal studies reveal that the incorporation of polyurethane into the epoxy skeleton increases the mechanical strength and decreases the glass transition temperature, thermal stability and heat distortion temperature. Whereas, the incorporation of bismaleimide having ester linkages into polyurethane modified epoxy systems increases the thermal stability, tensile and flexural properties and decreases the impact strength, glass transition temperature and heat distortion temperature. Surface morphology of polyurethane modified epoxy and bismaleimide modified polyurethane‐epoxy systems were studied using scanning electron microscopy. Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis and characterization of novel low‐dielectric cyanate esters

For the purpose of increasing the mobility of residual bisphenol A dicyanate ester (BADCY) during the final stage of curing and achieving a complete reaction of cyanate groups, a small quantity of monofunctional phenol was added to BADCY to form an imidocarbonate, or a small quantity of monofunctional cyanate esters was added to form cyanate ester copolymers. The proposed structures were confirmed with Fourier transform infrared, elemental analysis, mass spectrometry, and NMR spectroscopy. The thermal properties of the cured cyanate esters were measured with dynamic mechanical analysis, thermogravimetric analysis, and dielectric analysis. These data were compared with those for the cured BADCY resin. The cured modified cyanate esters exhibited a lower dielectric constant, a lower dissipation factor, and lower moisture absorption than the cured BADCY system. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2589–2600, 2004