高性能萘基环氧树脂的合成

采用化学结构改性的方法,以萘酚和福尔马林溶液为原料,合成了分子骨架中相对于苯基体积较大、刚性强、平面结构、疏水性高的萘环为主链结构环氧树脂-2,2'-二缩水甘油醚基-1,1'-联萘(DGEBN)和邻邻'-二缩水甘油醚基-二萘基-亚甲基(DGEFN);然后分别以双氰双胺(DICY)、4,4'-二氨基-二苯基甲烷(DDM)、4,4'-二氨基-二苯基砜(DDS)作为固化剂,对DGEBN、DGEFN、DGEBA固化体系性质进行研究;研究结果表明,萘基环氧树脂固化物比苯基环氧树脂(DGEBA)固化物具有更高的玻璃化转变温度(Tg),极好的热稳定性和较低的吸湿性,是一种高性能的新型环氧树脂体系.     

形状记忆氢化双酚A型环氧树脂的制备与性能

为研究聚丙二醇二缩水甘油醚(JH-230)对热固性形状记忆环氧树脂基本性能的影响,将异佛尔酮二胺(IPDA)与具有不同分子量比的氢化双酚A型环氧树脂(AL-3040)、聚丙二醇二缩水甘油醚(JH-230)共混,经完全固化制备出一种新型的形状记忆氢化双酚A型环氧树脂。借助傅里叶红外光谱仪(FT-IR)、差示扫描量热仪(DSC)、动态热机械分析仪(DMA)和拉伸-回复形状记忆测试分析了热固性形状记忆环氧树脂的分子结构以及JH-230对固化体系玻璃化转变温度、储能模量和形状记忆性能的影响。研究表明,JH-230可以增加固化体系链段的柔韧性;固化体系的玻璃化转变温度与动态模量随JH-230含量的增加而降低;该形状记忆氢化双酚A型环氧树脂体系具有良好的形状记忆性能,且形变完全回复时间随JH-230含量的增加而延长。     

高性能液晶环氧树脂的研究

采用环氧氯丙烷法合成液晶环氧化合物-4,4‘-二缩水甘油醚基二苯基酰氧(PHBHQ),用傅立叶变换红外光谱(FT—IR)、差示扫描量热(DSC)、广角X射线衍射(WAXD)等技术研究了PHBHQ与4,4’-二氨基二苯甲烷(DDM)固化反应的固化特性及固化物的力学性能。研究表明,PHBHQ在固化过程中能形成取向有序的介晶域,赋予PHBHQ／DDM固化物优异的综合性能。     

活性稀释剂苯基缩水甘油醚对BPF/DEDDM固化体系性能的影响

以苯基缩水甘油醚(PGE)为活性稀释剂,3,3′-二乙基4,4′-二氨基二苯甲烷(DEDDM)为固化剂,研究了PGE用量对双酚F环氧树脂(BPF)/DEDDM固化体系黏度、固化特性、固化物力学性能及热性能的影响。结果表明,PGE的加入有效改善了树脂胶液的黏度,当添加质量分数15%时,30℃树脂胶液的黏度为1034mPa.s,降低了74.3%;PGE的加入对固化特性影响较小,反应级数约为0.88;固化物的拉伸强度和断裂伸长率随PGE质量分数的增加而提高,质量分数15%时,固化物的拉伸强度和伸长率分别为35.3MPa和1.16%,比不加PGE时提高了14.8%和13.7%;耐热性能降低,然而当质量分数大于12.5%后趋于稳定,玻璃化转变温度接近123℃。     

活性稀释剂含量对E-51环氧树脂体系性能的影响

以1,4-丁二醇二缩水甘油醚作为活性稀释剂,研究了其含量对E-51/T403体系的固化特性及力学性能的影响.研究表明:随着稀释剂含量的增加,E-51/T403树脂体系的弯曲强度、弯曲模量都有不同程度的降低,但对E-51/T403体系固化特性影响较小.当1,4-丁二醇二缩水甘油醚的添加量小于15%时,E-51/T403体系具有较低的黏度和较好的力学性能.     

活性稀释剂含量对E-51环氧树脂体系性能的影响EI

以1,4-丁二醇二缩水甘油醚作为活性稀释剂,研究了其含量对E-51/T403体系的固化特性及力学性能的影响.研究表明:随着稀释剂含量的增加,E-51/T403树脂体系的弯曲强度、弯曲模量都有不同程度的降低,但对E-51/T403体系固化特性影响较小.当1,4-丁二醇二缩水甘油醚的添加量小于15%时,E-51/T403体系具有较低的黏度和较好的力学性能.     

含金刚烷结构环氧树脂的合成与性能

以1,3-二(4-羟基苯基)金刚烷(BHPA)和环氧氯丙烷(ECH)为原料,采用二步法合成了低分子量的1,3-二(4-羟基苯基)金刚烷二缩水甘油醚(DGEBAD),采用FTIR、1H-NMR和凝胶渗透色谱(GPC)分别对其结构和分子量进行了表征并滴定得到其环氧值;采用旋转流变仪对其流变性能进行了表征。使用4,4'-二氨基二苯基甲烷(DDM)固化DGEBAD,对固化DGEBAD-DDM树脂体系的力学性能、吸水率和耐热性进行了测试,得到的固化物的拉伸强度为90 MPa,玻璃化转变温度为163℃, 5%热失重温度高达401℃,吸水率比相同条件下环氧树脂E51-DDM固化物降低了31.60%。      

有机硅改性双酚F环氧树脂的性能

合成了脂肪族二官能度端环氧基聚二甲基硅氧烷、含酚羟基烷氧基硅烷及3,3′,3″-三羟基苯氧基硅烷三缩水甘油醚,研究了有机硅对环氧树脂力学性能的影响,并用TMA及化学分析方法研究了改性固化物的热性能和树脂/玻璃纤维复合材料的耐酸性。研究结果表明,3,3′,3″-三羟基苯氧基硅烷三缩水甘油醚可使环氧树脂的拉伸强度、弯曲强度分别提高10.4%及53.6%,线胀系数降低18.8%,抗开裂指数提高52.2%,同时保持固化物较高的玻璃化温度,提高耐酸性,是一种理想的环氧树脂新型改性剂。     

含不同扩链剂的聚叠氮缩水甘油醚基含能热塑性弹性体的合成与力学性能EI北大核心CSCD

采用不同碳链长度的小分子二元醇扩链剂乙二醇、丙二醇、丁二醇、戊二醇和己二醇合成了聚叠氮缩水甘油醚(GAP)基含能热塑性弹性体(ETPUE)。通过凝胶渗透色谱、傅里叶变换红外光谱、动态热机械分析测试和力学性能测试研究了不同扩链剂扩链的ETPUE的性能变化规律。结果表明,当碳原子数大于2时,偶数碳扩链剂的ETPUE的氢键化程度较高,力学性能好;奇数碳扩链剂的ETPUE的氢键化程度较低,力学性能较差;碳原子数为2时,由于链段很短,氢键化程度较低,性能较差。己二醇扩链的ETPUE的综合性能最佳。     

γ-缩水甘油醚氧丙基倍半硅氧烷/甲基丙烯酸缩水甘油酯复合材料的制备和性能

以γ-缩水甘油醚氧丙基倍半硅氧烷和甲基丙烯酸缩水甘油酯以及阳离子光引发剂复合组成固化体系,紫外光照固化获得γ-缩水甘油醚氧丙基倍半硅氧烷/甲基丙烯酸缩水甘油酯复合材料,研究γ-缩水甘油醚氧丙基倍半硅氧烷含量变化对材料本体性能及表面性能的影响。结果表明:材料硬度随γ-缩水甘油醚氧丙基倍半硅氧烷含量增大而增大,γ-缩水甘油醚氧丙基倍半硅氧烷含量变化对复合材料本体热性能无显著影响。复合材料表面疏水性随γ-缩水甘油醚氧丙基倍半硅氧烷含量增大而增大,耐水性增强。XPS结果表明随着γ-缩水甘油醚氧丙基倍半硅氧烷含量增大,材料表面C元素含量降低,O元素含量降低,Si元素含量增大。光固化复合体系有望作为UV固化涂料使用。     

Toughening mechanism for a rubber-toughened epoxy resin with rubber/matrix interfacial modification

For a rubber-toughened piperidine-DGEBA epoxy resin, the interface between the rubber particle and the epoxy resin matrix was modified by an epoxide end-capped carboxyl terminated butadiene and acrylonitrile random copolymer (CTBN). The end-capping epoxides used were a rigid diglycidyl ether of bisphenol-A (Epon 828), a short-chain flexible diglycidyl ether of propylene glycol (DER 736), and a long-chain flexible diglycidyl ether of propylene glycol (DER 732). The microstructures and the fracture behaviour of these rubber-modified epoxy resins were studied by transmission electron microscopy and scanning electron microscopy. Their thermal and mechanical properties were also investigated. In the rubber-modified epoxy resins, if the added CTBNs were end-capped by a flexible diglycidyl ether of propylene glycol (DER 732 or DER 736) before curing, the interfacial zone of the undeformed rubber particle, the degree of cavitation of the cavitated rubber particle on the fracture surface and the fracture energy of the toughened epoxy resin were all significantly increased. The toughening mechanism based on cavitation and localized shear yielding was considered and a mechanism for the interaction between cavitation and localized shear yielding that accounts for all the observed characteristics is proposed.     

自乳化水性环氧树脂的制备

采用聚醚醇二缩水甘油醚(PEGGE)、乙醇胺(MEA)及冰乙酸对双酚A环氧树脂(DGEBA)化学改性,在不需Lewis酸催化剂条件下制备低污染、高性能水性环氧树脂。首先,在物料摩尔比(MEA/PEGGE)2∶1,反应温度55℃,反应时间4h下,用PEGGE对MEA扩链合成MEA-PEGGE加成物;然后,在物料摩尔比(DGEBA/MEA-PEGGE)2∶1,反应温度65℃,反应时间5h下,用MEA-PEGGE加成物对DGEBA扩链,合成DGEBA-MEA-PEGGE加成物;再采用冰乙酸与DGE-BA-MEA-PEGGE加成物成盐,制备出具有良好水溶解分散性能的自乳化水性环氧树脂。该树脂涂膜性能优良,具有良好柔韧性和耐冲击性,改善了普通环氧树脂性能较脆的缺陷。     

环氧树脂的NM R 表征

用1H、13C 核磁共振波谱对二酚基丙烷环氧树脂E-51、缩水甘油胺型环氧树脂A G-80、脂环族缩水甘油酯TDE-85 的结构进行了表征, 并通过二维COSY 谱及1H-13C 化学位移相关谱对各共振峰进行了指认。      

含磷双环戊二烯酚醛固化剂的合成及固化环氧树脂的性能

合成了一种含磷酚醛型环氧树脂固化剂DCPD-DOPO,通过红外光谱和核磁共振谱对其化学结构进行了表征,采用凝胶渗透色谱测量了其相对分子质量。以DCPD-DOPO、苯酚型酚醛树脂(PF8020)或其复合物为固化剂,双酚A环氧树脂(DGEBA)为基料,制备了不同磷含量的阻燃环氧树脂。通过热重分析、差示扫描量热分析研究了环氧树脂固化物的热性能和阻燃性能;通过极限氧指数(LOI),垂直燃烧实验和锥形量热法研究了固化后环氧树脂固化物的燃烧特性。结果表明,DCPD-DOPO固化的环氧树脂的LOI可达31.6%,垂直燃烧性能达到UL94 V-0级,玻璃化转变温度(T_g)为133℃。采用DCPD-DOPO与PF8020复合物固化的环氧树脂的T_g提高到138℃以上,LOI值略有降低,但仍能通过UL 94V-0测试。DCPD-DOPO与PF8020添加DCPD-DOPO后,复合固化的环氧树脂的热释放速率峰值及总释热量较PF8020固化的环氧树脂大幅度降低。此外,还用Kissinger法对环氧树脂固化反应动力学进行了研究。     

Material characterization of blended epoxy resins related to fracture toughness

The present study describes the effect of the macromolecular modifications on the fracture toughness of an epoxy system. We synthesized epoxy networks by the reaction of diglycidyl ether of bisphenol A (DGEBA) with methyl-tetrahydro-phthalic anhydride (MTHPA), initiated by a tertiary amine. Several materials were obtained by adding a high molecular weight monomer to one with low molecular weight (both based on DGEBA) at different concentrations. In every case, a stoichiometric amount of MTHPA was employed. The glass transition temperature and the Angell’s fragility index, derived from thermo-viscoelastic properties, were used to characterize the materials. Relationship between these two parameters and the fracture properties, including the fracture toughness and the microscopic roughness of the fracture surfaces observed by atomic force microscope (AFM), was then investigated. We found that there were direct correlations among the glass transition temperature, the fragility, the fracture toughness, and the roughness. This study revealed that both the glass transition temperature and the fragility are effective for characterizing material in relation to the fracture toughness of the blended epoxy resins.     

聚醚/双酚A环氧甲基丙烯酸酯复合光固化膜的性能

由聚醚型聚丙二醇二缩水甘油醚和甲基丙烯酸合成了可光固化的聚丙二醇二缩水甘油醚二甲基丙烯酸酯(DMA),再按不同质量配比将此合成物与双酚A型环氧甲基丙烯酸酯(BEMA)混合,经紫外光照射得到复合光固化膜,然后对所得固化膜的耐热性、柔韧性、硬度、光泽度、可见光透过率和微观形貌进行表征.研究结果表明,复合膜兼具DMA和BEM...     

海因环氧树脂/DDS体系的制备与性能

合成了海因环氧树脂,采用红外光谱和核磁共振进行了表征,制备了海因环氧树脂/二氨基二苯砜(DDS)体系,研究了海因环氧树脂/DDS体系的固化反应特性及固化物的性能。结果表明,树脂体系在100℃~296℃有一放热峰,峰值温度为197℃,140℃的凝胶时间长于42 min,在180℃下仅8 min;树脂浇铸体的氧指数为26.6,弯曲强度为111MPa,弯曲模量为4.14 GPa,冲击强度为14.8 kJ/m2。     

Effect of structure on properties of vinyl ester resins

The paper describes the synthesis of vinyl ester resins based on diglycidyl ether of bisphenol-A (epoxy equivalent = 450–465 g/eq) (VR resin) and tetrabromobisphenol-A (epoxy equivalent = 380–420 g/eq) (VR-1 resin). The viscosity of styrenated VR resin was higher than VR-1 resin. The effect of styrene andα-methyl styrene on curing of VR resins was studied. An increase in styrene from 30 to 50 wt% resulted in an increase in gel time and a decrease in exothermic peak. Addition ofα-methyl styrene delayed and depressed the exotherm. The mechanical properties of VR resin sheets and glass fabric reinforced laminates were better than VR-1 resins; whereas LOI of VR-1 was higher. A resin formulation containing 20–30 wt% of VR: VR-1 showed optimum mechanical properties and LOI.     

Prestressed double network thermoset: preparation and characterization

An innovative scheme to prepare Prestressed double network (PDN) epoxies is presented using a judicious combination of tetrafunctional curatives that have similar molecular weights but different reaction kinetics. A diglycidyl ether of bisphenol A epoxy monomer was reacted stoichiometrically and sequentially with various molar ratios of an aliphatic polyetheramine curing agent and an aromatic curing agent. Deformation was imposed on the partially cured resins after the formation of the first network, and postcuring was conducted at 50% compressive strain. Physical properties of the resulting PDN epoxies were examined using thermomechanical analysis, dynamic mechanical analysis, uniaxial tensile test, and plane-strain fracture toughness test. The application of prestress resulted in no changes in glass transition temperature, coefficient of linear thermal expansion, and Young’s modulus. However, a marked increase in fracture toughness is observed, accompanied by strong birefringence and visible roughness on the fracture surface.     

溴化丙烯酸松香环氧树脂的合成及固化物的阻燃性

以丙烯酸松香和液溴为原料,合成了溴化丙烯酸松香;再与环氧氯丙烷进行酯化反应、闭环反应,合成了溴化丙烯酸松香环氧树脂。采用固化剂4,4′-二氨基二苯砜(DDS)对产物进行了固化。用红外光谱(FT-IR)、核磁共振谱(1H-NMR)等对产物进行了表征。在适宜的条件下,合成的环氧树脂的环氧值为0.26mol/100g。燃烧实验、热失重和阻燃性实验证明,溴化丙烯酸松香环氧树脂/DDS固化物具有较好的阻燃性。