光学检测传感器窗口自清洁耐刮擦涂层的制备及性能研究

Development of Self-cleaning and Scratch-resistant Coating on Surface of Optical COD Sensor Window

针对光学法化学需氧量(COD)监测传感器窗口长期在污水中工作,易附着污物、微生物,导致玻璃透光性下降进而寿命缩短的问题,设计制备了一种光学检测窗口用透明自清洁耐刮擦涂层,使细菌、藻类等生物无法黏附在玻璃表面,以保证检测效果。以两种含氟高分子乳液[聚四氟乙烯和六氟丙烯共聚物(F46)、四氟乙烯和全氟烷氧基乙烯基醚共聚物(PFA)]为前体,通过加入适量环氧树脂提升涂层性能。系统研究了复合体系的固含率和环氧树脂的添加量对涂层性能的影响。结果发现,当环氧树脂与含氟高分子固体质量比为1∶19时,制备得到的PFA基复合涂层透明,具有自清洁功能(疏水角可达127.8°),且耐刮擦性能优异。进一步向PFA基复合涂层中添加纳米银颗粒后,涂层的抑菌率达到41.9%。

It is easy for the window of optical chemical oxygen demand(COD)sensor working in sewage to attach dirt and microorganisms,which leads to the decrease of light transmittance of glass and the shortening of its service life.In this paper,aiming at this problem,a self-cleaning and scratch-resistant transparent coating was designed and prepared on the surface of sensor window,which could prevent bacteria,algae and other organisms from adhering onto the glass surface,thus ensuring the detection effect.Two fluorine-containing polymer emulsions,F46 and PFA,were selected as precursors.Epoxy resin was added to improve the adhesion between the coating and glass substrate,and the scratch resistance of the coating was improved.In this process,the effects of the solid content of the composite system and the amount of epoxy resin on the adhesion,light transmittance,hydrophobicity and scratch resistance of the coating were systematically studied.The results showed that when the mass ratio of epoxy resin to fluorine-containing polymer solid was 1:19,the prepared PFA-based composite coating was not only transparent and self-cleaning(the water contact angle up to 127.8°),but also had excellent scratch resistance.Furthermore,the antibacterial effect of PFA-based composite coating with silver nanoparticles was also investigated.The preliminary experiment confirmed that the antibacterial rate of the coating reached 41.9%.