摘要
为了改善气相二氧化硅(FS)/浇注型聚氨酯(PU)体系成型流动性,在制备预聚体的过程中,采用2,4-甲苯二异氰酸酯(TDI)进行改性获得异氰酸酯改性的二氧化硅(NCO@FS),通过原位聚合法制备了NCO@FS/PU弹性体复合材料。采用FTIR、XPS及动态接触角对NCO@FS及FS进行了表征。结果表明:FS的表面羟基与TDI的-NCO基团发生反应生成了氨酯基(-NHCOO),改善了FS与PU间的界面相容性及界面结合。复合材料中NCO@FS质量分数为1.5wt%时,NCO@FS/PU复合材料的拉伸和撕裂强度分别为57 MPa和110.5 kN/m,比纯浇注型PU分别提高了31.6%和23.6%;玻璃化转变温度由3.4℃下降到-11.2℃,损耗因子tanδ由0.59下降到0.46。异氰酸酯改性FS适合制备FS增强浇注型聚氨酯复合材料。
In order to improve the molding fluidity of fumed silica(FS)/cast polyurethane(PU)system,in the process of preparing prepolymer,the fumed silica(FS)was modified by 2,4-toluene diisocyanate(TDI)to obtain TDI modified silica(NCO@FS),and TDI modified silica/reinforced pouring polyurethane(NCO@FS/PU)elastomer composite material was prepared by in-situ polymerization.NCO@FS and FS were characterized by fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and contact angle testing.The results show that the active hydroxyl groups on the surface of FS react with the-NCO groups of TDI to form urethane groups aminoester group(-NHCOO),which improves the interfacial compatibility and interfacial bonding between silica and casting polyurethane.When the mass fraction of NCO@FS in the composite material is 1.5wt%,the tensile and tearing strengths of the NCO@FS/PU composite material are 57 MPa and 110.5 kN/m,respectively,which are 31.6%and 23.6%higher than that of pure casting PU.The glass transition temperature dropped from 3.4℃to–11.2℃,and the loss factor tanδdropped from 0.59 to 0.46.TDI modified fumed silica is suitable for preparing silica-reinforced cast polyurethane composites.
作者
周鑫
易玉华
ZHOU Xin;YI Yuhua(School of Mechanical&Automotive Engineering,South China University of Technology,Guangzhou 510640,China)
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2023年第2期852-859,共8页
Acta Materiae Compositae Sinica
基金
广州市科技计划项目(202102080477)。
