Application of organosilane coatings for improvedanti-adhesive properties enabling facilitated demoldingin polymer processing

Easy and residue-free demolding is an everlasting topic in the plasticsprocessing industry. Typically, facile ejection of the produced parts from themold is provided by separation agents (silicon sprays, surface coatings). In thiswork, a perfluoroalkyl-based organosilane coating is applied to exchangeablesubstrates of an injection mold. Besides the simple application, the coating canalso be restored easily in a procedure based on flame treatment. Coating andrecoating are proven by contact angle measurements with water, while theanti-adhesive effect and the related relief during demolding are evaluatedusing a special measuring device in an instrumented two-plate injection mold.The results reveal that the organosilane layer reduces the demolding forcesand the resulting static friction coefficient by 50%. Furthermore, multiplerecoating significantly improves the durability of the anti-adhesive coating.Based on these findings, the easily applicable and renewable organosilanecoating represents a suitable alternative to conventional release coatings.