聚甲基丙烯酸甲酯/环氧树脂互穿网络复合物的性能研究

使用环氧树脂（EP-618）对作为人工义齿材料的聚甲基丙烯酸甲酯进行了共混改性,通过使用胺类固化剂（XCT-802）、甲基六氢邻苯二甲酸酐（MeHHPA）及2-乙基-4-甲基咪唑（2E4MZ）3种不同类型的固化体系,经过物理共混及化学反应的方法制备出具有互穿网络结构的聚甲基丙烯酸甲酯／环氧树脂二元复合物,并讨论了不同环氧树脂用量对该复合物力学性能的影响。     

不同固化体系环氧树脂固化物的热解特性

为了研究不同固化体系下环氧树脂固化物的热解特性,采用DTG-60(AH)热重分析仪分析了氮气环境中不同固化体系的环氧树脂固化物在不同升温速率下的热分解特性。采用Kissinger法进行热解动力学分析,得到4种固化体系环氧树脂固化物的表观活化能和表观指前因子,采用Coast-Redfern法通过回归方程计算反应级数,基于上述热解动力学参数估算不同环氧树脂固化物的热老化寿命。结果表明：在氮气气氛中,选用二乙烯三胺(DETA)、间苯二甲胺(m-XDA)和2-乙基-4-甲基咪唑(2E4MZ)作为固化剂的环氧树脂固化物为二阶段热解,选用低分子聚酰胺(PA650)作为固化剂的环氧树脂固化物的热失重率受升温速率影响最小,但随着升温速率升高逐渐由二阶段热解过渡为三阶段热解;在10～40℃·min^-1的升温速率下,2E4MZ/EP体系固化物的起始热分解温度及最大失重速率温度最高;PA650/EP体系固化物热解过程中的平均表观活化能最高;耐热老化性能由高到低排序为PA650/EP、2E4MZ/EP、m-XDA/EP、DETA/EP。     

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。     

促进剂种类对EP/PN体系固化反应动力学的影响

在一定比例的环氧树脂(EP)和线型酚醛树脂(PN)固化剂中加入丁酮溶解好的促进剂,制备了EP/PN体系。研究了不同促进剂对于EP/PN体系的固化反应动力学的影响。研究结果表明,2-乙基-4-甲基咪唑(2E4MZ)和三苯基膦(TPP)均可加速EP/PN体系的固化。使用外推法确定两体系的凝胶温度、固化温度和后处理温度等特征温度,发现2E4MZ促进的固化体系其凝胶温度较低,而固化温度和后处理温度略高。同时利用Kissinger方程和Ozawa方程计算出2E4MZ促进体系的平均表观活化能为74.92 kJ/mol,TPP促进体系的平均表观活化能为78.59 kJ/mol。     

动态固化聚丙烯／环氧树脂共混物的制备工艺研究

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／环氧树脂共混物，研究了动态固化PP／环氧树脂共混物制备工艺条件即增容剂、固化剂、环氧树脂的环氧当量及其含量等因素对共混物力学性能的影响。实验结果表明，选择马来酸酐接枝的均聚聚丙烯(PP-g-MAH)作为增容剂，所制得的动态固化PP／环氧树脂共混物的力学性能较好。2-乙基-4-甲基咪唑(EMI-2，4)的适宜用量为1．2％(每100份环氧树脂使用4份)。环氧当量对共混物的性能影响不大。当环氧树脂的含量为5％～10％时，动态固化PP／环氧树脂共混物的综合性能明显好于PP，特别是具有较高的强度和模量。     

生物基呋喃甲基缩水甘油醚对环氧树脂固化物性能的影响

利用改进的合成工艺成功合成了高纯度的呋喃甲基缩水甘油醚(FGE),并用红外对其结构进行了表征。将FGE作为活性稀释剂添加到环氧树脂中,研究了FGE含量对树脂黏度及固化物热性能、涂膜力学性能的影响。结果表明,随着FGE含量的增加,树脂黏度急剧下降,固化物热稳定性下降,涂膜力学性能得到提升。当FGE含量为10%~15%时,环氧树脂黏度下降至2 000~4 000 mPa·s,且热稳定性良好,涂膜力学性能好。FGE的最佳含量范围是10%~15%。     

咪唑促进双氰胺固化环氧树脂体系固化动力学

采用差示扫描量热(DSC)法研究了2-乙基-4-甲基咪唑(2E4MI)的含量对双氰胺(DICY)固化环氧树脂体系固化动力学的影响。非等温DSC测试结果表明,2E4MI能大幅度降低DICY固化环氧树脂所需要的温度和活化能,从而加快反应的进行。当2E4MI用量为0.2份时,活化能最低为84.2 kJ/mol且整体活化能随固化度的变化较小、固化更均匀。在2E4MI最佳用量(0.2份)下对固化体系进行等温DSC以及潜伏性测试,结果表明,该体系在160℃下20 min内可完成固化,室温储存15 d的固化度仅为0.146,说明其适合用作快速固化环氧树脂储存体系。     

含有潜伏性催化剂的环氧树脂/酸酐体系的研究

使用固态聚胺与疏水性微粒子WS-12制备出一种潜伏性催化剂,评价了该催化剂在环氧树脂/甲基六氢苯酐固化体系中的催化固化作用。在25～50℃的范围内本固化体系长时间黏度变化平稳,而在150℃以上时具有高效的催化效果,显示出该催化剂具有优异的潜伏功能。该催化固化体系能适合于各种黏度的环氧树脂,当使用一种低黏度环氧树脂时,即m(环氧树脂6002):m(甲基六氢苯酐):m(潜伏性催化剂)=100:70:3时,其固化物显示出最佳的力学性能。     

脂环族环氧树脂/酸酐体系固化促进剂的研究

利用示差扫描量热仪研究了乙酰丙酮铝、三苯基膦、2-乙基-4-甲基咪唑(2E4MZ)等3种促进剂在脂环族环氧树脂(UVR-6103)/甲基六氢邻苯二甲酸酐(MHHPA)体系中的固化行为,通过Ellerstien方程计算得到了UVR-6103/MHHPA体系在3种促进剂作用下的固化动力学参数,其表观活化能分别为48.6,69.2,90.2kJ/mol,反应级数分别为0.96,2.09和1.60。     

低黏度环氧树脂高温固化的性能影响

研究了风电叶片用低黏度环氧树脂在70℃、90℃和110℃固化温度下固化物的性能变化。气相色谱–质谱分析低黏度环氧树脂主要由双酚A环氧树脂和1,4–丁二醇二缩水甘油醚组成,固化剂为多元胺的成分,再通过红外光谱对70℃、90℃和110℃3组样件进行分析,结果显示,随着固化温度升高,固化物中起到体型网络交联的醚键的含量呈下降趋势,同时羰基和亚甲基含量增加,这些都说明在此固化温度区间内,固化温度升高,高分子的交联度呈下降趋势。对环氧浇铸体和玻璃钢样件的力学性能测试显示,从70℃到110℃固化温度升高样件的各项力学性能呈下降趋势。     

液晶化合物增韧改性耐高温环氧树脂的研究

通过4氨基苯酚与对苯二甲醛加成缩合反应合成一种新型西佛碱单体(DP-1),然后通过DP-1与环氧氯丙烷在碱性条件下合成环氧化合物(EP-1)。对EP-1结构进行了傅里叶红外变换光谱、核磁共振、差示扫描量热分析,分析了其性能。通过EP-1对耐高温环氧树脂(AG-80)进行增韧改性,以4,4’-二氨基二苯砜（DDS）为固化剂,研究AG-80/DDS/EP-1固化体系的力学性能和热性能。结果表明,成功合成了一种新型液晶型环氧化合物EP-1,当EP-1含量为5 %时,冲击强度为23.27 kJ/m2;弯曲强度为126.39 MPa;弯曲模量为4.14 GPa;热变形温度为232.5 ℃。     

Curing behavior and properties of epoxy resins cured with the diamine having the quinoxaline or triazine structure

2,3-Bis(4-aminophenyl)quinoxaline (1a), 2,3-bis(4-aminophenyl)-6-methylquinoxaline (1b), and 5,6-bis(4-aminophenyl)-3-(2-pyridyl)-1,2,4-triazine (2) were studied as curing agents of epoxy resins. The exotherms on differential scanning calorimetry thermograms of the mixtures of diglycidyl ether of bisphenol A (DGEBA) with 1a, 1b, and 2 were observed at higher temperatures than that of the mixture of DGEBA with a commercially used diamine, for example, 4,4′-diaminodiphenylsulfone (DDS). However, the epoxy resin cured with 1a (EP-1a) showed higher tensile strength to stainless steel at 20°C than that cured with DDS, and the high tensile strength of EP-1a was maintained even at 180°C. The epoxy resin cured with 1b or 2 also possessed higher tensile strength at 20°C than that cured with DDS, but the high tensile strength lowered somewhat at 120°C. Using diamines 1a, 1b, and 2 as a curing agent improved heat distortion temperatures of the cured epoxy resins. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 69: 1737–1741, 1998     

Characteristics of epoxy resin cured with in situ polymerized curing agent

In order to improve the heat resistance of a cured epoxy resin together with reducing the viscosity of the resin composition, an epoxy resin was cured with a curing agent formed from the radical copolymerization of vinyl monomers during the cure process of the epoxy resin. N-phenylmaleimide and p-acetoxystyrene were used as vinyl monomers of the curing agent. The epoxy resin was cured by the insertion reaction of the ester group of the in situ polymerized curing agent and the epoxy group of the epoxy resin. In the cure system of the epoxy and the phenol resins, reduction of the viscosity of the resin composition was achieved by replacing some or all of the phenol resin with these monomers. When all phenol resins were replaced by these monomers, the viscosity of resin composition (0.01 Pa s at 70 °C) decreased by about 1/2000 compared with that of the system with only phenol resin (21 Pa s at 70 °C). The glass transition temperature (T_g) of the cured resin with no phenols was 174 °C, an improvement of 17 °C compared with that of the system cured with only phenol resin. The flexural strength of the new resins remained unchanged.     

脂肪族环氧化合物的合成及其共混树脂的研究

以聚丙二醇和环氧氯丙烷为原料合成出了低黏度的脂肪族环氧树脂。使用上述环氧树脂与双酚A型环氧树脂按不同的比例混合后,再加入大分子胺类固化剂,由此构筑出环氧树脂固化体系并对其黏度、凝胶时间和固化物的力学性能进行了表征。结果显示,该环氧树脂固化体系在常温下具有很低的黏度与较长的凝胶时间,其固化物的拉伸与弯曲性能较好,且冲击韧性有了明显的改善。     

Synthesis of Copolymers Containing Double Spiro Orthocarbonate and Used as Anti-shrinkage Additives in Epoxy Resin Composite

A novel copolymer containing a double spiro orthocarbonate structure, poly 3-methylene-9-methyleneoxy-3,9-Bis(hydroxymethyl)-1,5,7,11-tetraoxaspiro[5.5] undecane (SOC), was synthesized. The structure of SOC was confirmed by ¹H, ¹³C NMR and FTIR spectra. Prepolymer (SOCP) reacting from SOC and 2,4-toluene diisocynate (TDI) was prepared and used as anti-shrinkage additives in the cationic polymerization of epoxy resin (EP-51). The volume changes of the cured epoxy resin containing SOCP were investigated by density measurements with an electronic hydrometer. The mechanical properties of the modified epoxy resin were investigated by adhesive strength, impact strength and flexural strength, while thermal properties were investigated by thermal gravimetric analysis (TGA).     

复合材料缠绕成型用电子束固化环氧树脂体系研究

为了研究适合于缠绕成型的低粘度可电子束固化复合材料的耐热环氧树脂基体,研究了不同组成的电子束固化树脂体系的粘度与温度的关系、耐热性与辐射剂量的关系及浇注体的力学性能。研究表明,树脂EB-4在60℃时粘度为389 mPa.s,树脂辐射固化的最佳剂量为150 kGy,而且在150 kGy辐射固化的EB-1、EB-4的玻璃化转变温度Tg分别为212.96℃、214.77℃,EB-4树脂浇注体的拉伸强度可以达到52.7 MPa,拉伸弹性模量2.79 GPa,断裂延伸率为2.18%,是1种适用于室温或低温下缠绕成型的耐热电子束固化环氧树脂基复合材料树脂体系。     

A multi-element flame retardant for rail transit to improve the flame retardant performance of epoxy resin while reducing smoke density

A P/N/Si structure flame retardant DTBD was successfully synthesized by 3,5-diaminobenzoic acid, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), triphenylsilanol, and benzaldehyde. The chemical structure of DTBD was analyzed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectra, which showed that DTBD was successfully synthesized. By analyzing the curing behavior, the addition of DTBD promoted the curing of epoxy resin (EP). According to the limited oxygen index (LOI) and UL-94 vertical combustion tests, it can be shown that the introduction of DTBD makes the epoxy resin have good self-extinguishing properties. Py-GC/MS analysis showed that the phosphorus free radicals and ammonia generated in the gas phase of DTBD could quench and dilute by capturing reactive free radicals and refractory gases. DTBD could improve the tensile and flexural properties of epoxy resin. According to the European flame retardant standard EN45545-2, the Ds of EP-15 and EP-20 obtained HL1 grade. With the increase in DTBD content, the VOF₄ of modified EP also gradually decreased, and both EP-15 and EP-20 obtained HL2 grade.     

低黏度环氧树脂／反应性聚氨酯固化体系的研究

使用聚乙二醇与聚丙二醇的共聚物（PEG-PPG）和二苯基甲烷二异氰酸酯（MDI）为原料,在催化剂的存在下合成末端有异氰酸酯基的反应性聚氨酯。该反应性聚氨酯在催化剂XCT．cat57及固化促进剂XCT—cat37的存在下,再与一种低黏度双酚A型环氧树脂按不同的比例混合,由此组成了低黏度环氧树脂／反应性聚氨酯固化体系。研究了低黏度共混物的黏结效果,评价了其固化物的黏结强度。研究结果显示,当m（环氧树脂6002）：m（反应性聚氨酯）等于50：50时,共混树脂固化物具有最佳的力学性能。     

An epoxy resin-elastomer system for filament winding

Tests characterizing an epoxy system that contains 5 percent rubber and is suitable for wet-filament winding are described. The resin is a bisphenol-A rubberized epoxy diluted with an aliphatic diglycidyl ether and cured with an aromatic amine. The viscosity and pot life were measured and the progress of cure was monitored so an optimum cure could be chosen. Mechanical tests were performed on the cured resin. The low viscosity (0.95 Pa's) and long pot life (29.3 h) make for ease of processing. A cure cycle of 1.5h at 90°C plus 2 h at 130°C gives a cured resin having a glass transition temperature of 104°C. The heat-cured material has a tensile strength of 76.1 MPa and a modulus of 2.43 GPa. Kevlar 49 composites of 60-, 65-, and 70-volume-percent fiber were prepared and tested. Results are presented and compared to two other Kevlar 49/epoxy composites.     

环氧大豆油低聚物增韧环氧树脂胶粘剂

合成了三种环氧大豆油低聚物作为室温和高温固化环氧树脂增韧剂,对其增韧环氧体系的粘接性能和力学性能进行了考察。试验结果表明,环氧树脂低聚物对固化体系的初期粘度等性能没有影响,对固化体系粘接性能和力学性能等有较大影响。与未改性的环氧树脂相比,由顺丁烯二酸酐扩链的环氧大豆油低聚物改性的环氧树脂剪切强度提高了56.64%。