摘要
以无水乙醇为溶剂、正硅酸乙酯(TEOS)为包覆剂对纳米Zn O表面进行无机包覆,然后用硅烷偶联剂(KH-550)对其表面进行改性,将改性后的纳米Zn O(即Zn O/Si O2/KH550)对水性聚氨酯乳液进行改性,研究了改性纳米Zn O的用量对水性聚氨酯(WPU)乳液涂膜的吸水率、吸甲苯率和拉伸性能的影响,通过傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)和水接触角测试对纳米Zn O和WPU改性前后的结构及疏水性进行了表征。结果表明,改性后的纳米Zn O粒子团聚减少,疏水性提高。当改性纳米Zn O的添加量为聚氨酯中有机物质量的0.6%时,所制备的用改性纳米Zn O改性的WPU乳液涂膜性能较好,吸水率、吸甲苯率分别为20.35%和30.50%,低于未改性的WPU;拉伸强度达到13.45 MPa,水接触角较未改性WPU涂膜提高了25°。
The surface of nano-ZnO was inorganically coated by using absolute ethanol as solvent and tetraethyl orthosilicate （TEOS） as coating agent, and then modified by silane coupling agent KH550. A water-based polyurethane （WPU） emulsion was modified with the modified nano,ZnO （i.e. ZnO/SiO2/KH550）. The influences of the dosage of modified nano-ZnO on water absorption rate and toluene absorption rate as well as tensile strength of the water-based polyurethane emulsion film were studied. The structure and hydrophobicity of the nano-ZnO and water-based polyurethane before and after modification were characterized by Fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and water contact angle test. The results indicated that the aggregation of nano-ZnO particles is decreased after modification, and its hydrophobicity is improved. When the amount of modified nano-ZnO is 0.6wt% by total mass of organic compounds in polyurethane, the film of the water-based polyurethane emulsion modified by ZnO/SiO2/KH550 has good properties water absorption rate and toluene absorption rate are 20.35wt% and 30.50wt%, respectively, which are lower than that of the unmodified water-based polyurethane; tensile strength reaches 13.45 MPa; and water contact angle is increased by 25° as compared with that of the water-based polyurethane film without modification.
出处
《电镀与涂饰》
CAS
CSCD
北大核心
2014年第22期966-971,共6页
Electroplating & Finishing
关键词
水性聚氨酯
纳米氧化锌
改性
水接触角
疏水性
water-based polyurethane
nano-zinc oxide
modification
water contact angle
hydrophobicity
