Behavior Of Silicone Oil Secretion In Silicone Coating Based On Nanochannels

The complex marine environment puts forward higher requirements for the functional protection and durability of ship hull.Low surface energy silicone(PDMS)antifouling coating has become one of the focuses of new antifouling coating research because of its reliability in ship protection and non-toxicity to marine ecological environment.Among them,silicone(iPDMS)coating with lubricating oil shows an important application prospect because of its excellent lubricity and anti-adhesion of marine bacteria.However,i-PDMS coating has some problems,such as poor stability,loss of lubricating oil and difficulty in repairing.Under this background,this thesis proposes that porous anodic aluminum oxide(AAO)and polyethylene terephthalate(PET)with nanochannel structure are respectively embedded on the surface of iPDMS coating,and the corner capillary force of the channel can be used to realize the secretion of lubricating oil from the restricted channel to improve the recovery rate and stability of surface silicone oil.The influence of the introduction of nanochannels on the silicone oil precipitation behavior of i-PDMS coating was studied,and the anti-pollution,mechanical properties and mussel adhesion behavior of i-PDMS coating embedded with nanochannels were preliminarily discussed.This thesis provides experimental and theoretical basis for the preparation of longlasting lubricating coatings,and has important scientific significance.The main research contents of this thesis are as follows:(1)I-PDMS-AAO coating embedded with AAO nanochannels was prepared by embedding AAO nanochannels on the surface of i-PDMS prepolymer coating by template covering method.The effects of the amount of silicone oil and nanochannels on the morphology and surface wettability of silicone oil on the coating surface were investigated.The results showed that with the increase of silicone oil content,the precipitation morphology of lubricating oil on the surface of i-PDMS coating changed from small oil droplets with uniform distribution to non-uniform and discrete oil droplets.The precipitated morphology of i-PDMS-AAO silicone oil changed into a continuous film after embedding into AAO nanochannel,and the precipitated morphology of silicone oil could still recover quickly after many physical injuries.The introduction of nanochannels reduces the hysteresis of i-PDMS by about 10±2°,which indicates that the droplets falling on the surface of i-PDMS-AAO coating are easier to slide down.It is considered that the rapid secretion and self-repair performance of silicone oil in AAO channel with one-dimensional array structure is due to the capillary effect in the confined space formed between the tube wall and PDMS.(2)I-PDMS-PET coating with embedded PET was prepared by embedding PET polymer film with three-dimensional network channel structure on the surface of I-PDMS coating by template covering method,and the influence of three-dimensional network channel structure on silicone oil precipitation morphology and surface wettability of coating surface was explored.The results showed that the three-dimensional channel structure improved the precipitation rate and morphology of silicone oil,but failed to form a continuous film.Although the embedding of PET did not change the hydrophobicity of the coating surface,the hysteresis of the coating surface was reduced by about 5±2°.In this thesis,i-PDMS-AAO and i-PDMS-PET coatings were preliminarily explored to prevent mussel and dopamine adhesion.The results showed that the two coatings showed good adhesion to mussels and dopamine,and the mechanical properties of i-PDMS-PET coating obtained by adding PET film on the surface obviously enhanced the mechanical properties of i-PDMS coating.This study provides a simple and reliable method for preparing long-lasting continuous lubricating coatings.