高聚物改性锌铝水滑石的制备及对聚氨酯脲力学性能的影响

Preparation of Polymer Modified Zn-Al Layered Double Hydroxide and Reinforcement of Polyurethane-Urea

利用微反应器通过共沉淀法制备锌铝水滑石(Zn Al-LDH),将其与阴离子水性聚氨酯混合,通过表面修饰得到疏水性能提高的类水滑石杂化物(polymer-LDH,以下简称P-LDH),利用原位聚合法制备不同P-LDH含量的类水滑石/聚氨酯脲复合材料。采用红外光谱、X射线衍射和热重分析对P-LDH的结构与性能进行了分析,研究了聚氨酯脲/P-LDH复合材料的氢键化作用、结构、形貌及力学性能。结果表明,经表面修饰的类水滑石杂化物,其疏水性能明显提高,疏水角可达100°。复合材料中P-LDH的质量分数在1%～2%的范围内,对聚氨酯脲表现出优异的增强增韧效果。其中,拉伸强度由38. 6 MPa提高到51. 5 MPa,增幅约33. 6%,扯断伸长率由421%增至507%,提高20. 5%。

ZnAl-LDHs were prepared using microchannel reactor by co-precipitation,and then the P-LDHs with improved hydrophobic properties were obtained by surface modification with anionic waterborne polyurethane. The polyurethane-urea/P-LDH polymer composites with different P-LDH content were prepared by in situ polymerization method.The structure and properties of polymer modified P-LDH were analyzed by FT-IR,WAXD and TGA,and the hydrogen bonding reaction,structure,morphology and mechanical properties of polyurethane-urea/P-LDH polymer composites were investigated. The results show that the hydrophobic properties of the surface modified P-LDHs are obviously improved,and its water contact angle can reach 100°. P-LDHs with the mass fraction of 1% ～ 2% could play an excellent strengthening and toughening effect on the PUU/P-LDH polymer composite. The tensile strength of PUU/P-LDH polymer composite is increases from 38. 6 MPa to 51. 5 MPa. The elongation at break increases from 421% to 507%.