论文部分内容阅读
利用端氨基偶联剂KH-550对纳米SiO2进行表面改性,在超声场作用下制备疏水性纳米SiO2粒子,并将其均匀分散到蓖麻油(CO)-聚氨酯溶液,通过红外光谱(IR)、热重分析(TGA)和扫描电镜(SEM)等测试方法,探讨醇溶性聚氨酯的热稳定性、铅笔硬度和胶膜力学性能等。红外分析表明,PU大分子和纳米SiO2之间形成化学键,形成了Si—O—Si结构。当蓖麻油添加量为多元醇总质量的10%时,拉伸强度由原来的6.8 MPa增加到16.2 MPa,吸水率降低至原来的1/2。纳米SiO2颗粒掺杂量由0%增加到2%时,PU涂膜的失重速率最高点温度由原来的345℃提高至369℃,热分解温度也有所提高。涂膜热重曲线出现右移。
The surface modification of nano-SiO2 was carried out by using terminal amino coupling agent KH-550. Hydrophobic nano-SiO2 particles were prepared under ultrasonic field and dispersed into castor oil (CO) -polyurethane solution. , Thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM) and other test methods to investigate the thermal stability of the alcohol-soluble polyurethane, pencil hardness and mechanical properties of the film. Infrared analysis showed that the formation of Si-O-Si structure between the PU macromolecule and the nano-SiO2 forms a chemical bond. When the addition of castor oil is 10% of the total mass of polyol, the tensile strength increases from 6.8 MPa to 16.2 MPa, and the water absorption decreases to 1/2. When the content of nano-SiO2 particles increased from 0% to 2%, the highest temperature of the weight loss rate of PU coating increased from 345 ℃ to 369 ℃, and the thermal decomposition temperature also increased. The thermogravimetric curve appears right shift.