不同改性锌铝水滑石的制备及其对聚氨酯脲性能的影响

Preparation of modified Zn-Al layered double hydroxide and its reinforcement of polyurethane-urea

分别以十二烷基硫酸(SDS)和阴离子水性聚氨酯(以下简称P)为改性剂,通过超声助混技术对水滑石(LDHs)进行改性,制备不同修饰效果的水滑石杂化物(SDS-LDHs、P-LDHs)。利用原位聚合原理分别将ZnAl-LDHs、SDS-LDHs和P-LDHs与聚氨酯脲共混,得到聚氨酯脲/类水滑石复合材料。借助傅里叶红外光谱、X射线衍射、接触角测定对类水滑石杂化物的结构和性能进行表征,并研究SDSLDHs和P-LDHs对复合材料力学性能及热学性能的影响。结果表明,十二烷基硫酸钠以插层方式对ZnAl-LDHs进行修饰,阴离子水性聚氨酯通过表面修饰实现改性;改性后的ZnAl-LDHs疏水性能均明显提高,疏水角分别为90°、100°;复合材料中,有机改性的类水滑石杂化物对材料不仅有良好的增强增韧效果,而且可有效提高材料的热稳定性,其中以P-LDHs的效果最为显著。

The Zn-Al layered double hydroxide （I.DHs）can be modified with sodium dodecyl sulfate（SDS） or anionic waterborne polyurethane to obtain the modified （SDS LDHs,P LDHs） by sonication assisted treatment.SDS LDHs and P LDHs have been used as nanofiller to prepare a series of the polyurethane urea nanocomposies in situ polymerization method. The chemical structure and properties of SDS and Polymer modified LDH have been characterized by FT IR,XRD and contact an gle meter.The result showed that SDS were successfully intercalated into the LDH gallery,its contact angle was 90°, and the surface of LDH was modified with organic anions and its hydrophobicity has been improved,its contact angle was 100°.The modified LDH could play an excellent strengthening and toughening effect on the PUU nanocomposies,but also improve the thermal stability of materials. The effect of P LDH was the most signification.