四溴双酚A环氧树脂/二氨基二苯砜固化过程的研究

用高分子材料动态力学谱仪 (TBA)、示差扫描量热仪 (DSC)等方法研究了二氨基二苯砜 (DDS)固化四溴双酚A环氧树脂 (TBBPAER)的固化过程 ,讨论了固化时间、固化剂用量及固化剂的种类等因素对固化物玻璃化转变温度 (Tg)的影响。实验结果表明 ,随着固化时间的延长 ,固化产物的玻璃化转变温度逐渐升高 ,并且在固化初始阶段为一个值 ,到固化中间阶段变为两个值 ,最后到固化末期又为一个值 ,显示出固化产物的结构有所不同 ;适当增加固化剂的用量未超过理论用量的 2 0 %之前 ,可有效地提高固化产物的玻璃化转变温度Tg值 ;选择不同的固化剂 ,可获得具有不同玻璃化转变温度Tg值的固化产物。     

DGE-BHBTMBP/E-51/DDS固化物的研究

以4,4′-二氨基二苯基砜(DDS)为固化剂,用新型联苯芳酯型液晶环氧树脂[4,4′-双(4-羟基苯甲氧基)-3,3′,5,5′-四甲基联苯二缩水甘油醚](DGE-BHBTMBP)改性普通双酚A型环氧树脂(E-51),通过动态热机械性能分析、热重分析及扫描电子显微镜测试了DGE-BHBTMBP含量对DGE-BHBTMBP/E-51/DDS固化物的热性能和力学性能的影响。结果表明,加入DGE-BHBTMBP的E-51/DDS固化物的玻璃化转变温度(Tg)和初始分解温度都有所提高。加入质量分数为20%的DGE-BHBTMBP可使固化物的Tg和初始分解温度分别提高44℃和21.86℃。当其质量分数为4%时,固化物的力学性能明显提高,冲击强度和弯曲强度分别提高了136%和9%。     

稀释剂用量对环氧固化物玻璃化温度的影响

通过在双酚A型环氧树脂0164中添加不同用量的辛基缩水甘油醚,然后与脂肪胺固化剂NSH2001固化,测定固化物Tg的方法研究了稀释剂用量对环氧固化物玻璃化温度(Tg)的影响。结果表明,随着稀释剂用量的增多,固化体系凝胶时间变长、最高放热峰温度逐渐变低,Tg值逐渐下降。环氧稀释剂质量分数在20%以下时,其质量分数每增加2%,Tg下降约3～5℃。     

微波固化环氧树脂／氨基二苯醚树脂的耐热性能研究

以二苯醚树脂(DPO)为原料，合成了一类新型耐高温树脂一氨基二苯醚树脂(ANDPO)，用作双酚A环氧树脂(EP)的固化剂，以提高环氧树脂的耐热性。采用微波技术固化EP／ANDPO体系。通过FTIR定量研究了EP／ANDPO体系的反应程度，利用差示扫描量热法(DSC)和热重分析法(TG)研究了固化体系的耐热性能，并与热固化进行了比较。结果表明：微波固化显著提高了体系的固化速度和热性能。体系转化率为95％时，400W的微波只需10min即可完成固化，而热固化需要在150℃固化240min。微波固化产物的Tg、表观分解温度TA、温度指数Tzg分别为172．6℃、322℃和200℃。而热固化产品的Tg、TA、Tzg分别为163．5℃、306℃和189℃。两种固化方式所得产品的TA、Tzg均高于目前所用的芳香族胺类固化剂，显著提高了环氧树脂的耐热性能。     

硫脲改性胺环氧树脂固化剂的合成及性能研究

对硫脲改性胺(3,3′-二乙基4,4′-二氨基二苯基甲烷和二元脂肪胺A)固化剂固化环氧树脂进行了系统研究,分析了合成反应时间、反应温度和单体配料比对固化剂性能的影响,并进一步考察了固化剂与环氧树脂的最佳掺量比以及固化产物的热性能和力学性能。实验结果表明:反应时间为2.5 h,反应温度为130℃,3,3′-二乙基4,4′-二氨基二苯基甲烷与硫脲和二元脂肪胺A的物质的量比为1∶0.5∶0.4时,合成的固化剂以1∶3加入环氧树脂中,体系能在室温环境下1 h左右凝胶,该体系经室温固化再以100℃的温度后固化之后具有较好的耐热性能和冲击韧性。     

硅磷杂化物/环氧树脂固化物的性能研究

以γ-环氧丙氧基三甲氧基硅烷(KH-560)与磷酸反应合成了一种含磷硅烷偶联剂,将这种含磷硅烷偶联剂与硅溶胶按一定配比进行水解缩聚反应,得到一种硅磷杂化物,将该硅磷杂化物引入到双酚A环氧树脂(E-51),以4,4′-二氨基二苯基甲烷为固化剂,制备了硅磷杂化物/环氧树脂固化物。对该固化物的玻璃化转变温度、热失重、拉伸强度、极限氧指数(LOI)进行了测试。结果表明,该固化物玻璃化转变温度,700℃残炭量以及LOI均比纯环氧树脂固化物高,拉伸强度却下降较少。当硅磷杂化物的添加量占环氧树脂质量的50%时,该固化物的玻璃化转变温度可以达到178℃,极限氧指数可以达到28.2,与纯环氧树脂固化物相比,分别提高了18℃和25%。与纯环氧树脂固化物相比,该硅磷杂化物/环氧树脂固化物具有较好的阻燃性及热稳定性。     

环氧树脂/含磷有机硅杂化物固化体系的耐热性与阻燃性研究

利用γ(2,3-环氧丙氧基)丙基三甲氧基硅烷与磷酸反应制备了一种含磷有机硅杂化物,并利用红外光谱对这种含磷有机硅杂化物进行了结构表征。将这种含磷有机硅杂化物加入到双酚A环氧树脂/4,4'-二氨基二苯基甲烷体系制备了环氧树脂/含磷有机硅杂化物固化体系,对这种固化物进行了热失重分析,并测试了其玻璃化转变温度(Tg)和极限氧指数。结果表明,该固化物的Tg比纯环氧树脂固化物有所提高,初始分解温度比纯环氧树脂低,而高温残炭率有大幅提高;当含磷有机硅杂化物含量为30份时,固化物的Tg提高9 ℃,极限氧指数到达27.3 %,700 ℃残炭率达到34.1 %,比纯环氧树脂分别提高28 %和77.8 %。     

三官能团环氧树脂/复合固化剂体系的固化研究

以间苯二酚二缩水甘油醚和1,1,1-三对羟基苯基乙烷为原料合成了三官能团环氧树脂(TEP),通过DSC,FT-IR,动态热力学分析和耐化学介质性测试对比研究了其分别与4,4-二氨基二环己基甲烷(DDCM)以及2-乙基-4-甲基咪唑(2E4MZ)与DDCM的复合固化剂所组成体系的固化反应动力学、固化度及玻璃化转变温度(Tg)。结果表明,DDCM与2E4MZ的复合固化剂体系虽然表观活化能稍高,但固化放热量大,放热集中,有利于提高固化度;且其固化物Tg和耐腐蚀性均优于DDCM体系。     

联苯酚醛环氧树脂固化动力学及热性能研究

以4,4'-二氨基二苯砜(DDS)为固化剂,采用非等温示差扫描量热法(DSC)研究了联苯酚醛环氧树脂(BPNE)的固化动力学。通过外推法确定了体系的固化工艺。采用Kissinger、Ozawa法计算出固化体系的表观活化能,根据Crane理论计算得到该体系的固化反应级数。采用DSC,热重分析(TGA)研究了固化物的耐热性。结果表明:BPNE的固化工艺为160℃/2h+200℃/2h+230℃/2h;固化反应的活化能约为61.86kJ/mol,指前因子为5.27×105min-1,反应级数为1.1;玻璃化转变温度(Tg)为167℃,其10%热失重温度为398.1℃,800℃残炭率为29.37%,与双酚A环氧树脂/DDS固化物相比,分别提高了22℃,11.71%。     

苯酐固化邻甲酚醛环氧的热性能与热分解动力学

研究了邻甲酚醛环氧树脂(o CFER)与邻苯二甲酸酐固化物的热分解动力学,用动态力学谱仪测定了玻璃化温度(Tg)。讨论了固化剂用量、固化时间等因素对玻璃化转变温度(Tg)的影响。结果表明,固化体系的玻璃化温度随反应程度的增加而升高,当达到一定程度后,趋于一定值。利用热重分析仪(TGA)研究了完全固化产物的热分解动力学,说明热分解反应分2步进行。     

几种胺类固化剂对环氧树脂固化行为及固化物性能的影响

固化剂结构对环氧树脂的固化行为和固化物性能具有重要影响,本文研究了聚醚胺(D-230)、异佛尔酮二胺(IPDA)和3,3'-二甲基-4,4'-二氨基-二环己基甲烷(DMDC) 3种胺类固化剂与实验室自制的低翻度环氧树脂A进行固化反应.通过薪度分析、红外(FTIR)光谱分析、DSC分析等手段研究了环氧树脂与固化剂反应程度...     

Preparation and Application of a New Curing Agent for Epoxy Resin

A new curing agent based on palmitoleic acid methyl ester modified amine (PAMEA) for epoxy resin was synthesized and characterized. Diglycidyl ether of bisphenol A (DGEBA) epoxy resins cured with different content of PAMEA along with diethylenetriamine (DETA) were prepared. The mechanical properties, dynamic mechanical properties, thermal properties, and morphology were investigated. The results indicated that the PAMEA curing agent can improve the impact strength of the cured epoxy resins considerably in comparison with the DETA curing agent, while the modulus and strength of the cured resin can also be improved slightly. When the PAMEA/epoxy resin weight ratio is 30/100, the comprehensive mechanical properties of the cured epoxy resin are optimal; at the same time, the crosslinking density and glass transition temperature of the cured epoxy resin are maximal.     

Development of an epoxy system characterized by low water absorption and high thermomechanical performances

Water absorption and thermomechanical properties of epoxy systems based on multifunctional dicyclopentadiene epoxy novolac resin Tactix556 cured with 4,4′ diaminodiphenilsulfone (4,4′DDS) as curing agent has been studied. The base system was modified by the addition of a novel 40 : 60 PES : PEES (Polyethersulphone : Polyetheretheresulphone) amine‐ended copolymer to improve toughness properties. The effect of thermoplastic addition on water adsorption was studied by gravimetric experiments. The viscoelastic properties of the resulting blend were analyzed by means of dynamic mechanical thermal analysis. The formulated systems were compared with a system based on tetraglycidyl‐4,4′diaminodiphenylmethane resin (MY721) cured with 4,4′ diaminodiphenilsulfone. The use of Tactix556 resin showed that water uptake values were minimized while retaining high glass transition temperatures, and toughness values were found in the same range of standard toughened matrices used for aerospace composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4880–4887, 2006     

Multifunctional epoxy resins

The curing behavior of epoxy resins prepared by reacting epichlorohydrin with 4,4′-diaminodiphenyl methane (DADPM)/4,4′-diaminodiphenyl ether (DADPE) or 4,4′-diaminodiphenyl sulfone (DDS) was investigated using DDS and tris-(m-aminophenyl)phosphine oxide (TAP) as curing agents. A broad exothermic transition with two maxima were observed in the temperature range of 100–315°C when TAP was used as the curing agent. The effect of varying DDS concentration on curing behavior of epoxy resin was also investigated. Peak exotherm temperature (T_exo) decreased with increasing concentration of DDS, whereas heat of curing (ΔH) increased with an increase in amine concentration up to an optimum value and then decreased. Thermal stability of the resins, cured isothermally at 200°C for 3 h, was investigated using thermogravimetric analysis in a nitrogen atmosphere. Glass fiber-reinforced multifunctional epoxy resin laminates were fabricated and the mechanical properties were evaluated. © 1993 John Wiley & Sons, Inc.     

固化剂对环氧玻璃鳞片涂层性能的影响

以双酚A环氧树脂(E20)为主要成膜物,层片状玻璃鳞片和云母氧化铁为主要填料,辅助以铝粉、氧化铁红颜料,以及各种助剂和溶剂,再分别加入固化剂脂肪族胺加成物、聚酰胺TY-650,制得高固体分厚浆型环氧玻璃鳞片涂料。通过常规的力学性能(涂层的硬度、耐冲击性、柔韧性、附着力等)和耐腐蚀性测试,对比了不同固化剂对环氧玻璃鳞片涂层性能的影响。研究结果表明,脂肪族胺加成物与环氧树脂交联固化的玻璃鳞片涂层的硬度、附着力以及交流阻抗值都较高,具有良好的综合性能,加入铝粉对基体可起到阴极保护作用。     

Organic rare-earth compounds as a new latent accelerator for curing of epoxy/anhydride system

Summary A seriesof organic rare-earth compounds has been found to be a latent accelerator for curing the epoxy resin/anhydride system. Incorporation of rare-earth ions into the epoxy resin caused an increase in the glass transition temperature (Tg) of the cured resin and the significant improvement in the dielectric and mechanical properties at high temperature which should be attributed to the higher Tg.     

表面组装用贴片胶的研制

为了改善传统贴片胶(SMA)的固化性能,以不同种类的环氧树脂(EP)作为基体树脂、不同潜伏性固化剂复配作为复合固化剂,制备了三种表面组装用SMA。采用差示扫描量热(DSC)法初步确定了固化剂的用量,并对三种SMA的玻璃化转变温度(Tg)和主要性能进行了对比试验。结果表明:以两种EP复配作为基体树脂,其SMA的综合性能优于单一EP基体树脂;当w(固化剂)=35%、w(触变剂)=6%时,该SMA可以在110℃、152 s条件下完全固化,其铺展值≤4.6%、塌落值≤5.4%、拉伸剪切强度为14 MPa且Tg值为89.7℃,说明该SMA既能快速固化,又具有较高的粘接强度和可修复性。