Compositions comprising organopolysiloxane resins consisting of units of the general formula R a R 1 b (OR 2) c SiO (4-a-b-c)/2, wherein R may be the same or different and is a hydrogen atom or monovalent, SiC-bonded, optionally substituted hydrocarbon radicals free of aliphatic carbon-carbon multiple bonds, R 1 may be the same or different and is monovalent, SiC-bonded, optionally substituted hydrocarbon radicals having aliphatic carbon-carbon multiple bonds, R 2 may be the same or different and is a hydrogen atom or monovalent, optionally substituted hydrocarbon radicals, a is 0, 1, 2 or 3, b is 0 or 1 and c is 0, 1, 2 or 3, with the proviso that in formula the sum of a+b+c <3, in at least one unit of the formula b=1, in at least 50% of the units of the formula a+b=1 and in at most 10% of the units of the formula a+b=3, based in each case on all siloxane units of the formula in organopolysiloxane resin, organic compounds having at least one unit of the formula CR 3 2 =CR 3 -CO-Z-, wherein R 3 may be the same or different and is a hydrogen atom, cyano radical -CN or a monovalent, optionally substituted hydrocarbon radical, which may be interrupted by heteroatoms, Z may be the same or different and is -O- or -NR 5 - and R 5 may be the same or different and is a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical, which may be interrupted by heteroatoms initiators, fillers and amines. organopolysiloxane resins consisting of units of the general formula R a R 1 b (OR 2) c SiO (4-a-b-c)/2, wherein R may be the same or different and is a hydrogen atom or monovalent, SiC-bonded, optionally substituted hydrocarbon radicals free of aliphatic carbon-carbon multiple bonds, R 1 may be the same or different and is monovalent, SiC-bonded, optionally substituted hydrocarbon radicals having aliphatic carbon-carbon multiple bonds, R 2 may be the same or different and is a hydrogen atom or monovalent, optionally substituted hydrocarbon radicals, a is 0, 1, 2 or 3, b is 0 or 1 and c is 0, 1, 2 or 3, with the proviso that in formula the sum of a+b+c <3, in at least one unit of the formula b=1, in at least 50% of the units of the formula a+b=1 and in at most 10% of the units of the formula a+b=3, based in each case on all siloxane units of the formula in organopolysiloxane resin, R may be the same or different and is a hydrogen atom or monovalent, SiC-bonded, optionally substituted hydrocarbon radicals free of aliphatic carbon-carbon multiple bonds, R 1 may be the same or different and is monovalent, SiC-bonded, optionally substituted hydrocarbon radicals having aliphatic carbon-carbon multiple bonds, R 2 may be the same or different and is a hydrogen atom or monovalent, optionally substituted hydrocarbon radicals, a is 0, 1, 2 or 3, b is 0 or 1 and c is 0, 1, 2 or 3, with the proviso that in formula the sum of a+b+c <3, in at least one unit of the formula b=1, in at least 50% of the units of the formula a+b=1 and in at most 10% of the units of the formula a+b=3, based in each case on all siloxane units of the formula in organopolysiloxane resin, organic compounds having at least one unit of the formula CR 3 2 =CR 3 -CO-Z-, wherein R 3 may be the same or different and is a hydrogen atom, cyano radical -CN or a monovalent, optionally substituted hydrocarbon radical, which may be interrupted by heteroatoms, Z may be the same or different and is -O- or -NR 5 - and R 5 may be the same or different and is a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical, which may be interrupted by heteroatoms R 3 may be the same or different and is a hydrogen atom, cyano radical -CN or a monovalent, optionally substituted hydrocarbon radical, which may be interrupted by heteroatoms, Z may be the same or different and is -O- or -NR 5 - and R 5 may be the same or different and is a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical, which may be interrupted by heteroatoms initiators, fillers and amines.