为了改进环氧树脂(EP)由于自身固化后形成交联网状结构而呈脆性断裂的特性,对其进行填充改性,使用苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)与纳米二氧化硅(SiO2)复合填充,以提升材料的力学性能。通过相转移催化法对SBS进行环氧化处理,得到环氧化程度为29.8%的环氧化SBS(ESBS),然后复合纳米SiO2对EP进行协同填充。通过核磁氢谱仪、红外光谱仪确定SBS的环氧化程度,然后使用热重分析仪、万能材料试验机和扫描电镜等测试分析了复合材料的力学性能及微观结构,主要研究了不同填料添加量及不同填充方式对复合材料的影响。结果表明,ESBS环氧化程度高低对复合材料的性能有一定影响,环氧化程度过低时,增韧效果不明显;过高时,会导致分散不均匀材料韧性反而降低。单一填充纳米SiO2可以提高复合材料的韧性;当ESBS添加量为0.5%、SiO2添加量为0.4%时,复合材料的拉伸强度提高19.52%,断裂伸长率提高19.73%,复合材料由脆性断裂转为韧性断裂,增韧效果明显。
In order to improve the brittle fracture of epoxy resin(EP) due to the formation of cross-linked network structure after self-curing,the EP was modified by filling,using the composite filling of styrene butadiene styrene block copolymer (SBS) and nano-silica (SiO2) to improve the mechanical properties of the material.The SBS was subjected to epoxidation treatment by phase transfer catalysis to obtain an epoxidized styrene butadiene styrene block copolymer (ESBS) with the epoxidation degree of 29.8%wt.,and then the composite nano-SiO2 was used to synergistically fill the EP.The degree of SBS epoxidation was determined by nuclear magnetic resonance spectroscopy and infrared spectroscopy.Then the mechanical properties and microstructure of the composites were analyzed by thermogravimetric analyzer,universal material testing machine and scanning electron microscopy.The effect of the amount of the main fillers and different filling methods on the composite were studied.The results shown that the degree of epoxidation of ESBS had a certain effect on the properties of the composite.When the degree of epoxidation was too low,the toughening effect was not obvious.When the degree of epoxidation was too high,the unevenness of dispersion in the material was reduced.Filling nano-SiO2 can improve the toughness of the composite.When the addition amount of ESBS was 0.5%wt.and the addition amount of SiO2 was 0.4%wt.,the tensile strength of the composite increased by 19.52%,the elongation at break increases by 19.73%,and the composite material turned from brittle fracture.For ductile fracture,the toughening effect was obvious.
[1] 王春红,王利剑,任子龙,等.SiO2-竹纤维协同改性对环氧树脂基复合材料摩擦磨损性能的影响[J].复合材料学报,2019,36(7):1633-1639.
[2] Barbakadze K,Brostow W,Hnatchuk N,et al.Tribology of novel antibiocorrosion coatings[J].Materials Research Innovations,2015,19(3):227-232.
[3] Jayan J S,Saritha A,Joseph K.Innovative materials of this era for toughening the epoxy matrix:a review[J].Polymer Composites,2018,39(S4):E1959-E1986.
[4] Mohan P.A critical review:the modification,properties,and applications of epoxy resins[J].Polymer-Plastics Technology and Engineering,2013,52(2):107-125.
[5] Uyor U O,Omah A D,Aigbodion V S,et al.Effects of carbonized particles on microstructure and mechanical properties of epoxy resin[J].International Journal of Advanced Manufacturing Technology,2019,17(4):4283-4292.
[6] 尹术帮,杨杰,刘新东,等.环氧树脂增韧改性方法及机理研究进展[J].热固性树脂,2013,28(4):46-52.
[7] 李洁.聚合物/乙烯基功能化二氧化硅纳米复合粒子的制备、表征及性能[D].武汉:武汉理工大学,2013.
[8] 李静.氟硅改性SiO2纳米涂层的表面结构与疏水性能调控研究[D].杭州:浙江理工大学,2016.
[9] 郭等锋.纳米二氧化硅/聚氨酯协同改性环氧树脂冲蚀磨损性能研究[D].兰州:兰州交通大学,2018.
[10] 王铁钢,蒙德强,李柏松,等.三靶共溅射纳米复合Cr-Al-Si-N涂层的制备及摩擦学性能研究[J].表面技术,2019,48(9):78-86.
[11] Shafabakhsh G,Rajabi M,Sahaf A.The fatigue behavior of SBS/nanosilica composite modified asphalt binder and mixture[J].Construction and Building Materials,2019,229(116796):1-7.
[12] Cheng W,Xu Z,Chen S,et al.Compatibilization behavior of double spherical TETA-SiO2@PDVB janus particles anchored at the phase interface of acrylic resin/epoxy resin (AR/EP) polymer blends[J].ACS Omega,2019,4(18):17607-17614.
[13] 朱德智.增强增韧的环氧树脂/二氧化硅纳米复合材料的制备与研究[J].塑料工业,2017,45(6):66-69.
[14] Liu Y Z,Sun Y,Zeng F L,et al.Effect of nano SiO2 particles on the morphology and mechanical properties of POSS nanocomposite dental resins[J].Journal of Nanoparticle Research,2014,16(12):2736.
[15] 杨建军,何亚东,张志成,等.纳米SiO2和PP-g-MAH对玻纤增强PP复合材料性能的影响[J].玻璃钢/复合材料,2016(9):49-54.
[16] 中国国家标准化管理委员会.树脂浇注体性能试验方法:GB/T 2567—2008[S].北京:中国标准出版社,2008.
[17] Jian X,Hay A S.Catalytic epoxidation of styrene-butadiene triblock copolymer with hydrogen peroxide[J].Journal of Polymer Science Part A:Polymer Chemistry,1991,29(8):1183-1189.
[18] 国家标准总局.塑料邵氏硬度试验方法:GB/T 2144—1980[S].北京:中国标准出版社,1980.
[19] 张忠厚,张光辉,陈荣源,等.聚天冬氨酸酯型聚脲增韧结构型环氧树脂及其机理[J].材料导报,2019,33(6):1061-1064.
