绢云母和硅烷偶联剂KH550对聚氨酯/Al-Sm2O3复合涂层耐盐水性能的影响

目的提高聚氨酯(PU)/Al-Sm_2O_3复合涂层的耐盐水性能。方法以绢云母和硅烷偶联剂KH550改性PU/Al-Sm_2O_3复合涂层,系统研究改性前后涂层的微结构、红外发射率、近红外反射率及力学性能经盐水腐蚀后的变化规律,并对其成因进行分析探讨。结果经绢云母和KH550改性后的涂层与改性前的涂层相比,其微结构在腐蚀前后几乎保持不变,经盐水腐蚀相同时间时,改性涂层具有更低的1.06μm近红外反射率,更优异的力学性能。改性涂层经盐水腐蚀10 d后,其硬度、附着力和耐冲击强度仍可保持在3H、1级和50 kg×cm。结论绢云母和KH550改性可明显提高PU/Al-Sm_2O_3复合涂层的近红外低反射性能及力学性能对盐水腐蚀的稳定性。

Effects of Sericite and Silane Coupling Agent KH550 on Saline Water Resistance of Polyurethane/Al-Sm2O3 Composite Coatings

The work aims to improve saline water resistance of polyurethane(PU)/Al-Sm2O3 composite coatings. PU/Al-Sm2O3 composite coatings were modified with sericite and silane coupling agent KH550, and varying patterns of microstructure, infrared emissivity, near-infrared reflectivity and mechanical properties of the coatings before and after modification were sys-tematically investigated, then the causes were analyzed and discussed. Compared with the unmodified coatings, microstructure of the modified sericite and KH550 coatings was almost unchanged after corrosion, and the modified coatings had lower near-infrared reflectivity of 1.06 μm and better mechanical properties under the same corrosion conditions of saline water. Hardness, adhesion strength and impact strength of the modified coatings were maintained at 3H, grade 1 and 50 kg·cm 10 days after saline water corrosion. Sericite and KH550 modification can improve the stability of low near-infrared reflection property and mechanical properties of PU/Al-Sm2O3 composite coatings to saline water corrosion.