Production of silicone elastomer coatings by dipping preheated metal workpieces in a low-viscosity silicone bath including a heat stabilizer and a crosslinking inhibitor

摘要

Production of silicone elastomer coatings comprises dipping preheated metal workpieces in a bath comprising a hydrogen-functional polyorganosiloxane (POS) and an alkenyl-functional POS and curing the coating. Production of adherent or nonadherent silicone elastomer coatings comprises: (a) dipping preheated metal workpieces in a bath comprising a silicone composition crosslinkable by a polyaddition reaction between at least one POS having at least one pendant and/or terminal silicon-bonded hydrogen atom and at least one POS having at least one pendant and/or terminal silicon-bonded alkenyl group with 3-6 carbon atoms; (b) draining the dipped workpieces; (c) heating the workpieces at 100-300 deg C for a time sufficient to crosslink the silicone elastomer; and (d) either releasing and recovering the nonadherent coatings or recovering workpieces with adherent coatings. The method comprises using a bath that has a viscosity of 10,000-200,000 mPa.s (at 25 deg C) and includes: (i) at least one crosslinking inhibitor selected from acetylenic alcohols, maleates and silicones functionalized with unsaturated groups; (ii) at least one additive for heat-stabilizing the crosslinked elastomer; (iii) optionally at least one filler; (iv) optionally at least one compatibilizing agent; (v) optionally at least one adhesion promoter or mold release agent; (vi) optionally at least one flame retardant; and (vii) optionally at least one pigment.