【作者】 赵立英；

【导师】 官建国；

【作者基本信息】 武汉理工大学 ， 材料学， 2010， 博士

【摘要】 环氧树脂是一种通用型热固性树脂,固化后的环氧树脂具有力学性能好、耐酸碱腐蚀、固化收缩率小和绝缘强度高等优点,但其脆性大、冲击强度不高的缺点限制了其应用范围,尤其是作为阻尼材料在低温和室温下的应用。而且环氧树脂难溶于水,只溶于芳香烃、酮类以及醇类等有机溶剂,因此传统环氧树脂的应用大多伴随着有机溶剂的使用。现在人们在追求涂料高性能的同时,对于节约资源、保护生态环境越来越重视,传统溶剂型涂料的污染问题已经引起了整个社会的高度重视,因此开发绿色环保型的水性环氧树脂已成为涂料工业发展的主要趋势,具有广阔的应用前景。本论文针对传统环氧树脂的增韧和水性环氧树脂制备工艺中存在的若干问题,提出了采用即含刚性结构单元又含柔性亲水聚醚链段的端氨基聚醚(ATPE)化合物用于环氧树脂增韧及其水性化制备技术,同时研究了端氨基聚醚增韧改性环氧树脂和非离子型水性环氧树脂的结构和性能。主要研究内容和结论如下：以聚乙二醇(PEG)和氯化亚砜等为原料成功合成了双端氯代聚乙二醇(PEGCl2),进而分别与对羟基苯胺、对羟基苄胺和对羟基苯乙胺在无溶剂条件下通过相转移催化剂四丁基溴化铵(TBAB)催化,合成了端氨基聚醚α,ω-对苯胺基聚乙二醇(BAPTPE)、α，ω-对苯甲胺基聚乙二醇(BAMPTPE)和α,ω-对苯乙胺基聚乙二醇(BAEPTPE),研究了反应条件对端氨基聚醚合成和BAMPTPE用量对BAMPTPE-DGEBA环氧树脂胶粘剂力学性能的影响规律。采用三种不同聚乙二醇(PEG)链段长度(MPE)的柔性端氨基聚醚(BAMPTPE)与双酚A环氧树脂(DGEBA)固化反应,制备了无微相分离的和耐冲击性能优良的AB交联型热固性环氧树脂。研究了MPE对环氧树脂固化产物微观结构和力学性能的影响规律。发现在环氧树脂固化网络中引入两端均能与DGEBA产生化学连接的PEG链段能有效避免其与DGEBA链段产生相分离结构,提高环氧树脂交联网络中的自由体积分数和缩短DGEBA链段的松弛时间,从而改善产物的力学性能。采用三种不同端氨基结构的端氨基聚醚(BAPTPE、BAMPTPE和BAEPTPE)与双酚A环氧树脂(DGEBA)固化反应,制备了无微相分离和低温下耐冲击性能优异的交联型热固性环氧树脂。发现ATPE化学结构(在氨苯基间引入Lalkyl)对环氧树脂固化特性和固化产物微观结构和力学性能均有显著的影响。在端氨基聚醚的苯环与氨基间引入-CH2-和-CH2CH2-, ATPE-DGEBA固化体系的反应活化能明显降低；固化产物交联网络中刚性基团间以σ-σ键链接,可通过σ-σ键的旋转改变构象,缩短交联网络中DGEBA链段的应力松弛时间,从而改善固化产物的力学性能。以不同结构的固化剂(BAMPTPE600、D400和二氨基二苯甲烷)和双酚A环氧树脂E-44为原料,通过叠层法制备了玻璃化转变温度范围最大可达180℃且力学性能优异的梯度聚合物材料。同时系统地研究了不同固化剂组份对制备的梯度交联聚合物材料结构、力学性能和阻尼性能的影响规律。将PEG链段以不同的方式引入到环氧树脂交联网络中制备了无微相分离的PEG接枝聚合物(PEGF51/m-XDA)和PEG交联聚合物(F51-BAMPTPE)。通过动态力学性能测试研究了聚醚链段长度以及聚醚链段在环氧树脂交联网络中的存在形式对聚合物动态力学性能的影响规律。发现PEG链段通过仲氨基与环氧树脂的环氧基加成反应以支链的方式引入环氧树脂交联网络结构中,在提高PEG链段与环氧树脂分子相容性的同时,PEGF51/m-XDA固化产物的阻尼性能得到明显改善。以对甲氧基聚乙二醇苯甲胺(p-MPEGBA)和双酚A环氧树脂为原料制备了分散相粒径为纳米级的非离子型自乳化水性环氧树脂。研究了MPE对水性环氧树脂(MPEGE44)水乳液分散相粒径和D230-MPEGE44固化产物力学性能和耐水性能的影响规律。发现在环氧树脂分子结构中引入通过化学连接的PEG链段使MPEGE44获得良好水分散性能的同时可提高交联网络的自由体积分数和缩短环氧树脂链段的松弛时间,从而改善D230-MPEGE44固化产物的耐冲击性。以-甲氧基-ω-N-异丙醇基-对苯甲胺基聚乙二醇改性多官能团的酚醛环氧树脂F51制备了非离子型活性环氧树脂乳化剂(PEGF51)。发现在环氧树脂分子结构中引入通过化学连接的PEG链段使PEGF51获得良好水分散性能的同时可提高环氧树脂交联网络中的自由体积分数和缩短环氧树脂链段的松弛时间,从而改善D230-PEGF51/F51固化产物的力学性能。PEGF51与F51摩尔比为1:3时可制备出同时具有优异的拉伸强度、模量、断裂应变、冲击性能和低吸水率的D230-PEGF51/F51环氧树脂。更多还原

【Abstract】 Cured products of epoxy resins generally have high mechanical strength, low creep and curing shrinkage, strong anticorrosion, and good electrical properties, and are thus widely used in structural adhesives, composite materials, surface coatings and electrical laminates. However, these materials also have a main shortcoming of low toughness due to their high crosslinking density and are therefore prone to fracture at room temperature and low temperature. On the other hand, epoxy resins are insoluble in water and only soluble in aromatics, ketones, alcohols and other organic solvents. So the application of traditional epoxy resin is limited to the organic solvent systerms. Recentlly, the traditional solvent-based paint contamination problem has aroused great attention of the entire community. Therefore, environment-friendly water-based epoxy resin has been the main trend in the development of coatings industry. In this paper, a series of amino-terminated poly(ethylene glycol) compounds (ATPE) which including both regid phenyl and flexible poly(ethylene glycol) segment were synthesized and were used to reinforce or to prepare water-based epoxy resin. The structure and physical properties of the amino-terminated poly(ethylene glycol) compounds modified epoxy resin and nonionic water-based epoxy resin were studied.The main contents and conclusions are described as follows:Theα,ω-bischlorine end-capped polyethyleneglycol with different moleculer were synthesized by polyethyleneglycol and thionyl chloride. Three amino-terminated polyethers were prepared byα,ω-bischlorine end-capped polyethylene glycol and 4-aminophenol (4-hydroxybenzylamine and 4-hydroxyphenethylamine) in the condition of phase transfer catalysis. Effects of reaction condition on the purity of ATPE and effect ofα,ω-bisaminophenyl terminated poly(ethylene glycol) content on the mechanical properties of BAMPTPE-DGEBA epoxy resin adhesives were studied respectively.An advanced amorphous AB-type thermosetting resin without nanophase separation was synthesized by directly moulding diglycidyl ether of bisphenol A (DGEBA) andα,ω-bisaminophenyl terminated poly(ethylene glycol) (BAMPTPE). The stress-strain curves, dynamic mechanical thermal analysis and morphologies of impact fracture surfaces of the cured products were investigated as functions of flexible poly (ethylene glycol) segment length (MPE). The results show that the homogeneous epoxy resin without nanophase separation are available by incorporating poly (ethylene glycol) segments into epoxy crosslinked networks via chemically linked with DGEBA at both terminals, beneficial for increasing free volume fractions and strain relax rates.A high performance thermosetting epoxy resin crosslinkable at room temperature is obtained via directly moulding diglycidyl ether of bisphenol A (DGEBA) and flexibleα,ω-bisamino(n-alkylene)phenyl terminated poly(ethylene glycol). The influences of the n-alkylene inserted into amino phenyl of flexible amino-terminated polythers (ATPE) on the curing kinetics, mechanical properties and fractographs of the ATPE-DGEBA cured products were studied. The results show that the insertion of n-alkylene group into the aminophenyl group of the ATPE, on one hand, can remarkably enhance the reactivity of amine with epoxy, much accelerating the curing rate of the ATPE-DGEBA systems. On the other hand, it can significantly increase the strain relaxation rate and decrease glass transition temperature of the ATPE-DGEBA cured products, resulting in slight decrease of the Young’s modulus and tensile strength, and significant increase of the toughness and elongation of the ATPE-DGEBA cured products.A facile approach to the preparation of a gradient polymer with a broad damping temperature has been synthesized using diglycidyl ether of bisphenyl A epoxy resin (E44) and three kind of curing agents, i.e. the amino terminated polyether (BAMPTPE600),4,4’-Diaminodiphenylmethane (DDM) and polyoxypropylene diamines (D400). The dynamic mechanical properties, morphology and mechanical behaviors of the three gradient polymers (BAMPTPE600-D400/E44, D400-DDM/ E44 and BAMPTPE600-DDM/E44) were investigated. The results show that the BAMPTPE600-DDM/E44 gradient polymer exhibits a wide transition range of over 180℃and excellent mechanical properties. The mechanism of forming the gradient structure is also discussed. Polyether amine grafting epoxy resins were prepared through propylene oxide modified p-methoxypolyethylene glycol benzylamine (PO-p-MPEGBA) reacting with the epoxy group of the polyfunctional group novolac epoxy resin(F51). The structure of PEG grafted epoxy resins (PEGF51) were characterized by using infrared spectroscopy. Dynamic mechanical properties, morphology, and damping behavior of the PEGF51 cured by m-xylene-diamine (m-XDA) were investigated as function of poly (ethylene glycol) segment length (MPE). The results show that the homogeneous polymers without nanophase separation are available by chemically incorporating poly (ethylene glycol) segments into epoxy resin crosslinked networks. When MPE is extended, the glass transition temperature of PEGF51/m-XDA cured product decreased. The as-obtained homogeneous polymer exhibits its potential as a material for damping application by a broad loss factor (tanδ)≥0.3 spanning a temperature range of approximately 52℃.A new kind of nonionic self-emulsified waterborne epoxy resin (MPEGE44) containing hydrophilic polyether segment was synthesized by using bisphenol A epoxy resin (E44) and p-methoxypolyethylene glycol benzylamine (p-MPEGBA). The impact mechanical properties and water absorption of the D230-MPEGE44 cured products were investigated as functions of flexible PEG chain length (MPE). The results show that waterborne epoxy resins are available by chemically incorporating PEG segment into epoxy resin molecular structure. It is beneficial to increase hydrophilicity of MPEGE44 and strain relaxtion rates of the D230-MPEGE44 crosslinked networks.A new kind of nonionic type active waterborne epoxy resin emulsifier containing hydrophilic polyether segment was prepared through reacting propylene oxide modified p-methoxypolyethylene glycol benzylamine (PO-p-MPEGBA) with the epoxy group of the polyfunctional group novolac epoxy resin (F51). The modified epoxy resins (PEGF51) have good emulsification to low molecular weight epoxy resin F51. The results show that the active epoxy resin emulsifiers are available by incorporating poly (ethylene glycol) segments into epoxy molecular structure via chemically linked with F51, beneficial for increasing hydrophilic and strain relax rates. The D230-PEGF51/F51 cured products which exhibit excellent tensile strength, modulus and impact strength at room temperature are obtained by the facile optimization of the concentration of the PEGF51/F51.更多还原