绢云母对聚氨酯/Sm_2O_3复合涂层自然老化性能的影响

Influence of Sericite on Natural Aging Property of Polyurethane/Sm_2O_3 Composite Coatings

目前有关绢云母对近红外吸收涂层自然老化性能的影响鲜见研究报道。采用绢云母改性聚氨酯(PU)/Sm_2O_3复合涂层,从涂层微结构、近红外吸收性能和力学性能角度系统研究了改性前后涂层经4个月自然老化后性能的变化规律。结果表明:改性前后涂层的微结构对自然老化均具有良好的稳定性,随自然老化时间的延长并未出现开裂、起泡、粉化等现象。改性后涂层在同等自然老化条件下对1.06μm近红外光的反射率要明显低于未改性涂层。改性前后涂层的硬度对自然老化具有良好的稳定性;未改性涂层的附着力、耐冲击强度及柔韧性受自然老化影响明显,但经绢云母改性后可得到明显加强,经自然老化4个月后仍然可达到1级、500 N·cm及3 mm。

Polyurethane（PU）/Sm2O3 composite coatings were modified by sericite, and the variation of property of natural aging for 4 months of coating before and after modification was systematically investigated, including microstructure, near-infrared absorption property and mechanical properties. Results indicated that the microstructure of the coatings before and after modification had good stability. The phenomenon such as cracking, blistering and chalking did not occur with the natural aging prolongation. The reflectivity at 1.06 μm of the modified coatings was sig- nificantly lower than that of unmodified coatings under the same natural aging conditions. The coatings had good stability during the natural aging process before and after modification. The adhesion strength, impact strength and flexibility of the unmodified coatings were significantly affected by the natural aging, but they were significantly strengthened after serieite modification, which still reached 1 grade, 500 N ·cm and 3 mm after natural aging for 4 months.