Research On Anti-adhesion Film Preparation Toward Surface Constraint Stereolithography And Its Impact On The Peel Strength

Mask projection stereolithography is a three-dimensional printing technology which can solidify the whole parts layer in one single exposure process.Stripping failure is one of the main troubles in bottom-up projection-based stereolithography.Stripping failure mainly caused by excessive adhesion power between solidified photosensitive resin layer and the bottom of resin groove,it will lead to processing failed and life of resin groove reduction.Therefore,decrease the adhesion power between solidified layer and bottom of resin groove has become the basic framework to solve the stripping failure.In order to reduce the adhesion power,this paper mainly present the PDMS film with anti-adhesion performance.The main steps of PDMS film preparation contain synthesis of silica spheres,molecular self-assembly on wafer surface,dry plasma etching and nano-structure transformation on PDMS film.A surface cohesive based finite element simulation has completed to verify the anti-adhesion performance of PDMS film.Finally,a battery of tests has completed to test the light-admitting quality,hydrophobic property and anti-adhesion performance of PDMS film.The main work and achievements are as follows:By the research on synthesis of silica and pulling method of molecular self-assembly on wafer surface,a silicon substrate with ordered nanostructures has been prepared.Silica beads which meet the requirement of diameter have been prepared by the research of silica bead synthetic process and its main control parameters.Moreover,according to the study on pulling method of molecular self-assembly,molecular self-assembly on wafer surface has achieved.The PDMS film with low surface energy was acquired by the research on dry plasma etching and nano-structure turnover formwork.By the research of dry plasma etching and effects controlled by process parameters,the transformation of namo-structure from silica bead mask to silicon substrate was completed.In addition,such silicon substrate has been used to support the secondary nano-structure transformation from silicon substrate to PDMS film.A couple of surface based cohesive finite element models have been established.Its results of stress nephogram and contact force comparison between model with nano-textured PDMS film and model with glossy PDMS film testify the anti-adhesion performance of PDMS layer.The result of further contrast simulation shows,compare with triangle and circular foursquare nano-structure owns the best anti-adhesion performance.A battery of tests was taken to test the light-admitting quality,hydrophobic property and anti-adhesion performance of PDMS film.The results of tests present that the light-admitting quality can be enhanced by using PDMS film.Furthermore,the ordered nano-structures on the surface of PDMS film have lower surface energy which can improve hydrophobic performance of film surface.Finally,the result of pressure test between bottom with PDMS film and bottom without PDMS film shows the adhesive power between solidified resin layer and the bottom of resin groove has been reduced from 27N to 1.4N,and this result proved the performance of anti?adhesion of PDMS film.