超疏水PDMS改性聚氨酯/黄铜复合涂层的制备及性能表征

Fabrication and Performance Characterization of PDMS Modified Polyurethane/Brass Composite Coating with Super-hydrophobicity

本工作以片状黄铜粉为功能颜料、纳米SiO_(2)为微纳结构改性剂、聚二甲基硅氧烷(PDMS)改性聚氨酯(PU)为黏合剂,采用简单的玻璃棒刮涂法制得了一种同时具有超疏水性能和较低红外发射率的复合涂层,系统探讨了PDMS/PU质量比、总填料添加量(质量分数)及黄铜粉/纳米SiO_(2)质量比对涂层性能的影响规律。结果表明:PDMS/PU配比对涂层附着力和疏水性能具有重要的影响,当PDMS/PU的质量比为1∶9时,涂层具备突出的超疏水性能,附着力可达1级,水接触角和滚动角分别可达155°、5°。总填料添加量对涂层性能的影响明显,随着填料添加量的增加,涂层发射率有所增大,光泽度有所降低。当总填料添加量为50%时,涂层表面可形成明显的乳突状微纳粗糙结构,从而可使涂层具备突出的超疏水性能。黄铜粉/纳米SiO_(2)配比会显著影响涂层的发射率和疏水性能,当黄铜粉/纳米SiO_(2)的质量比为6.5∶3.5时,涂层可具备良好的综合性能和突出的自清洁性能,涂层发射率可低至0.716,光泽度和附着力分别为1.8级、1级,水接触角和滚动角分别为151°、8°。

Acomposite coating with super-hydrophobicity and low infrared emissivity was prepared by glass rod scraping method using flake brass powders,nano-SiO_(2)and polydimethylsiloxane(PDMS)modified polyurethane(PU)as functional pigments,micro-nano structural modifier and adhesive,respectively.The effects of the ratio(mass ratio)of PDMS to PU,the addition amount(quality score)of total fillers and the ratio(mass ratio)of brass powder to nano-SiO_(2)on the coating properties were systematically discussed.The results show that the mass ratio of PDMS to PU has an important influence on the adhesion strength and hydrophobic properties of the coating.When the mass ratio of PDMS to PU is 1∶9,the coating has outstanding super-hydrophobic properties,the adhesion strength of the coating can reach 1 grade,the water contact angle and sliding angle can reach 155°and 5°,respectively.The total filler addition amount has a significant impact on the coating performance.With the increase of the filler addition amount,the emissivity of the coating increases and the glossiness decreases.When the total filler content is 50%,the coating surface can form an obvious papillary micro-nano rough structure,so that the coating has outstanding super-hydrophobic properties.The mass ratio of brass powder to nano-SiO_(2)can obviously affect the emissivity and hydrophobic properties of the coating.When the mass ratio of brass powder to nano-SiO_(2)is 6.5∶3.5,the coating can have good overall performance and outstanding self-cleaning performance.At this time,the emissivity of the coating can be as low as 0.716;the glossiness and adhesion strength are grade 1.8 and grade 1,respectively;the water contact angle and sliding angle are 151°and 8°,respectively.