Abstract: Organopolysiloxane compositions curable into elastomeric state, whether in single- or two-component form, comprise an .alpha.,.omega.-dihydroxypolydiorganopolysiloxane oil, a crosslinking agent therefor, optionally, inorganic fillers and an adhesion promoter, and a catalytically effective amount of a pentacoordinated tin monochelate produced by reacting a tin oxide with a .beta.-dicarbonyl compound and a carboxylic acid.

Abstract: Novel platinum/olefin complexes, useful for the hydrosilylation curing catalysis of hardenable organopolysiloxane compositions, are facilely prepared by reacting a platinum halide with at least one alkali or alkaline earth metal carbonate or bicarbonate in the presence of an aliphatic triene ligand having the general formula: ##STR1## wherein R.sub.1 is a linear or branched chain alkyl radical having from 1 to 6 carbon atoms, and R.sub.2 is R.sub.1 or a linear or branched chain alkenyl radical having from 2 to 16 carbon atoms and at least one site of ethylenic unsaturation, and said complex having a ratio, in gram-atoms of halogen to gram-atoms of platinum, ranging from virtually 0 to 4.

Abstract: Novel platinum/olefin complexes, useful for the hydrosilylation curing catalysis of hardenable organopolysiloxane compositions, are facilely prepared by reacting a platinum halide with at least one alkali or alkaline earth metal carbonate or bicarbonate in the presence of an alkenylcyclohexene ligand having the general formula: ##STR1## wherein R.sub.1 is an alkenyl radical having from 2 to 6 carbon atoms, and R.sub.2 is a hydrogen atom or an inert organic radical, and said complex having a ratio, in gram-atoms of halogen to gram-atoms of platinum, ranging from virtually 0 to 4.

Abstract: Novel platinum/olefin complexes, useful for the hydrosilylation curing catalysis of hardenable organopolysiloxane compositions, are facilely prepared by reacting a platinum halide with at least one alkali or alkaline earth metal carbonate or bicarbonate in the presence of an aliphatic triene ligand having the general formula: ##STR1## wherein R.sub.1 is a linear or branched chain alkyl radical having from 1 to 6 carbon atoms, and R.sub.2 is R.sub.1 or a linear or branched chain alkenyl radical having from 2 to 16 carbon atoms and at least one site of ethylenic unsaturation, and said complex having a ratio, in gram-atoms of halogen to gram-atoms of platinum, ranging from virtually 0 to 4.

Abstract: Gelation-resistant, high pot life organopolysiloxane compositions adapted for antiadhesive/release coating applications, are comprised of (1) at least one substantially straight-chain organopolysiloxane having a viscosity ranging from about 50 to 100,000 mPa.s at 25.degree. C. and containing at least x alkenyl unsaturated hydrocarbon groups bonded to a silicon atom, per molecule, wherein x.gtoreq.2, (2) at least one organohydropolysiloxane crosslinking agent having a viscosity ranging from about 10 to 100,000 mPa.s at 25.degree. C. and containing at least y hydrogen atoms bonded to silicon atoms, per molecule, wherein y.gtoreq.2, (3) a catalytically effective amount of a platinum group metal crosslinking catalyst, and (4) an effective amount of at least one azodicarboxylate gelation inhibitor which is inert to the activity of said catalyst (3), but in insufficient amount as to prevent the crosslinking of said polysiloxanes (1) and (2) under crosslinking conditions.

Abstract: Curable organopolysiloxane compositions useful, e.g., for the production of anti-stick coatings, comprise (1) an organopolysiloxane, (2) an organohydropolysiloxane, (3) a platinum group metal hardening catalyst, and (4) a platinum catalysis inhibitor comprising an acetylenic .alpha.-ketone in an amount which inhibits gelation at ambient temperatures but does not prevent cross-linking at temperatures in excess thereof.

Abstract: Novel organopolysiloxane/polyurethane block copolymers which are thermoplastic elastomers and which possess good thermomechanical properties, are comprised of the following recurring units (A) and (B): ##STR1## wherein Z is a divalent radical which comprises a polysiloxane block and has the formula: ##STR2## in which Y and Y' are each a divalent radical having one of the formulae: ##STR3## wherein T and T' comprise the divalent or trivalent residue having from 1 to 20 carbon atoms of an unsaturated isocyanate or alcohol having one of the formulae:OCN--T--CR.sub.1 .dbd.CR.sub.2 R.sub.3HO--T--CR.sub.1 .dbd.CR.sub.2 R.sub.3 ##STR4## or an oxygen, sulfur, silicon, nitrogen, ester or amide interrupted such T or T' residue, and further wherein R.sub.1, R.sub.2 and R.sub.3 are each hydrogen, alkyl or aryl, with the proviso that two of the radicals R.sub.1 and R.sub.