Liquid carboxyl-terminated poly（butadiene-co-acrylonitrile）（CTBN）-epoxy resin（EP） prepolymers were prepared with different contents of CTBN.The chemical reactions between EP and CTBN were characterized by Fourie...Liquid carboxyl-terminated poly（butadiene-co-acrylonitrile）（CTBN）-epoxy resin（EP） prepolymers were prepared with different contents of CTBN.The chemical reactions between EP and CTBN were characterized by Fourier ransform infrared（FTIR） spectroscopy and gel permeation chromatography（GPC）.The scanning electron micrograph（SEM） and dynamic mechanical analysis（DMA） of curing films showed phase separation,and the rubber particles were finely dispersed in the epoxy matrix.Mechanical properties analysis of curing films showed that impact strength and elongation at break increased significantly upon the addition of CTBN,indicating good toughness of the modified epoxy resins.Thermogravimetric analysis（TGA） showed that the incorporation of CTBN had little effect on the thermal stability of EP.Fusion-bonded-epoxy（FBE） powder coatings modified with CTBN-EP prepolymers were prepared.The experimental results demonstrate the ability of CTBN-EP prepolymers,toughening technology to dramatically enhance the flexibility and impact resistance of FBE coatings without compromising other key properties such as corrosion protection.展开更多
CTBN-EP prepolymers were synthesized from CTBN and epoxy resin under the catalysis of HTMAB. FTIR analyses indicate the formation of ester group between the carboxyl group of CTBN and the oxirane group of epoxy resin....CTBN-EP prepolymers were synthesized from CTBN and epoxy resin under the catalysis of HTMAB. FTIR analyses indicate the formation of ester group between the carboxyl group of CTBN and the oxirane group of epoxy resin. The viscosity of modified prepolymer increases with CTBN content increasing, but the epoxy value of the prepolymer decreases greatly. DSC analyses verify that CTBN affects the curing process of CTBN-EP/PEA system. Mechanical testing presents the improved toughness of CTBN-EP/PEA curings for the decrease of tensile strength, flexural strength and compressive strength, and increase of impact strength and elongation-at-break with the CTBN content increasing. SEM micrographs show the rubber phase with many holes in diameter about 0.5-1.5 μm is formed when CTBN content is lower than 10 phr. However, the pattern of SEM graph shows some stalactite-like strips when CTBN content is higher than 15 phr. Furthermore, the SEM image of 25 phr CTBN sample forms a kind of co-continuous structure.展开更多
采用2,4,6-三（二甲氨基甲基）苯酚为促进剂,甲基四氢邻苯二甲酸酐为固化剂,以端羧基液体丁腈橡胶（CTBN）增韧改性酚醛环氧树脂。利用傅里叶红外光谱,动态热力学分析仪、静态热力学分析仪及力学性能测试研究了CTBN用量对复合材料性能...采用2,4,6-三（二甲氨基甲基）苯酚为促进剂,甲基四氢邻苯二甲酸酐为固化剂,以端羧基液体丁腈橡胶（CTBN）增韧改性酚醛环氧树脂。利用傅里叶红外光谱,动态热力学分析仪、静态热力学分析仪及力学性能测试研究了CTBN用量对复合材料性能的影响。结果表明,CTBN质量分数15%时,复合材料的力学性能最佳,冲击强度、拉伸强度、断裂伸长率分别为11.722 k J/m^2、24.022 MPa、10.099%,较纯环氧树脂分别提高了32.53%、147.45%、99.86%,此时储能模量降低最为明显。而材料的玻璃化转变温度降低,热膨胀系数呈现出先降低后升高的趋势。展开更多
基金Funded by the National Science and Technology Pillar Program of China(No.2007BAE15B02)
文摘Liquid carboxyl-terminated poly（butadiene-co-acrylonitrile）（CTBN）-epoxy resin（EP） prepolymers were prepared with different contents of CTBN.The chemical reactions between EP and CTBN were characterized by Fourier ransform infrared（FTIR） spectroscopy and gel permeation chromatography（GPC）.The scanning electron micrograph（SEM） and dynamic mechanical analysis（DMA） of curing films showed phase separation,and the rubber particles were finely dispersed in the epoxy matrix.Mechanical properties analysis of curing films showed that impact strength and elongation at break increased significantly upon the addition of CTBN,indicating good toughness of the modified epoxy resins.Thermogravimetric analysis（TGA） showed that the incorporation of CTBN had little effect on the thermal stability of EP.Fusion-bonded-epoxy（FBE） powder coatings modified with CTBN-EP prepolymers were prepared.The experimental results demonstrate the ability of CTBN-EP prepolymers,toughening technology to dramatically enhance the flexibility and impact resistance of FBE coatings without compromising other key properties such as corrosion protection.
基金Funded by the Defense Advanced Research Project (No.51312040404)
文摘CTBN-EP prepolymers were synthesized from CTBN and epoxy resin under the catalysis of HTMAB. FTIR analyses indicate the formation of ester group between the carboxyl group of CTBN and the oxirane group of epoxy resin. The viscosity of modified prepolymer increases with CTBN content increasing, but the epoxy value of the prepolymer decreases greatly. DSC analyses verify that CTBN affects the curing process of CTBN-EP/PEA system. Mechanical testing presents the improved toughness of CTBN-EP/PEA curings for the decrease of tensile strength, flexural strength and compressive strength, and increase of impact strength and elongation-at-break with the CTBN content increasing. SEM micrographs show the rubber phase with many holes in diameter about 0.5-1.5 μm is formed when CTBN content is lower than 10 phr. However, the pattern of SEM graph shows some stalactite-like strips when CTBN content is higher than 15 phr. Furthermore, the SEM image of 25 phr CTBN sample forms a kind of co-continuous structure.
文摘采用2,4,6-三（二甲氨基甲基）苯酚为促进剂,甲基四氢邻苯二甲酸酐为固化剂,以端羧基液体丁腈橡胶（CTBN）增韧改性酚醛环氧树脂。利用傅里叶红外光谱,动态热力学分析仪、静态热力学分析仪及力学性能测试研究了CTBN用量对复合材料性能的影响。结果表明,CTBN质量分数15%时,复合材料的力学性能最佳,冲击强度、拉伸强度、断裂伸长率分别为11.722 k J/m^2、24.022 MPa、10.099%,较纯环氧树脂分别提高了32.53%、147.45%、99.86%,此时储能模量降低最为明显。而材料的玻璃化转变温度降低,热膨胀系数呈现出先降低后升高的趋势。
