Abstract: A silicon containing adduct having the formula (I) wherein X is an electron withdrawing group selected from the group consisting of carbonyl and sulphone groups, sulphonium and phosphonium salts; R is selected from the group consisting of hydrogen, linear and branched alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, alkaryl, aralkyl, alkoxyaryl, alkoxyalkyl, oligoalkoxyalkyl, di-alkylaminoalkyl, N-aryl-N-alky-laminoalkyl, hydroxyalkoxy, alkoxy, alkenyloxy, alkynyloxy, cycloalkoxy, cycloalkenyloxy, cycloalkynyloxy, aralkoxy, alkoxyaryloxy, alkoxyalkoxy, oligoalkoxyalkoxy, di-alkylaminoalkoxy, N-aryl-N-alkylamino-alkoxy, acyloxy, acyloxyalkyl, N-diacyl-iminoalkyl groups, organosilane, organosiloxane, hydroxyaryl, hydroxyalkenyl, hydroxyalkynyl and hydroxy groups and any of the above groups substituted with one or more hydroxyl or xzwitterionic group Z, or R—X— is a nitrile group; R3 and R4 are individually selected from the group consisting of hydrogen, linear and branched alkyl, alkenyl,

Abstract: A polyion complex (PIC) is formed of an anionic soluble polymer formed from ethylenically unsaturated monomers including at least one anionic or monomer and a cationic soluble polymer formed from ethylenically unsaturated monomer including at least one cationic monomer, in which the monomers used to form at lest one of the polymers comprise a switterionic monomer and in which the monomers used to form at least one of the polymers include non-ionic monomer, preferably C1-24 alkyl(meth)acrylate, in which the overall ratio of anionic groups to cationic groups in the PIC is in the range 1.5:1 to 1:1.5, and in which the polymers are combined in ratios to provide a PIC in which there are units derived from zwitterionic monomer in an amount in the range 1 to 70 mole % based on total monomer derived units in the PIC and there are units derived from non-ionic monomer in an amount in the range 0 to 60 mole % based on total monomer derived units in the PIC.

Abstract: A silicon containing adduct having the formula (I) wherein X is an electron withdrawing group selected from the group consisting of carbonyl and sulphone groups, sulphonium and phosphonium salts; R is selected from the group consisting of hydrogen, linear and branched alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, alkaryl, aralkyl, alkoxyaryl, alkoxyalkyl, oligoalkoxyalkyl, di-alkylaminoalkyl, N-aryl-N-alky-laminoalkyl, hydroxyalkoxy, alkoxy, alkenyloxy, alkynyloxy, cycloalkoxy, cycloalkenyloxy, cycloalkynyloxy, aralkoxy, alkoxyaryloxy, alkoxyalkoxy, oligoalkoxyalkoxy, di-alkylaminoalkoxy, N-aryl-N-alkylamino-alkoxy, acyloxy, acyloxyalkyl, N-diacyl-iminoalkyl groups, organosilane, organosiloxane, hydroxyaryl, hydroxyalkenyl, hydroxyalkynyl and hydroxy groups and any of the above groups substituted with one or more hydroxyl or zwitterionic group Z, or R—X— is a nitrile group; R3 and R4 are individually selected from the group consisting of hydrogen, linear and branched alkyl

Abstract: An insoluble polymer is deposited in a body cavity for instance to embolize a vein or pack an aneurysm, the polymer having pendant zwitterionic groups to improve biocompatibility. The insoluble polymer is preferably formed by an in situ gelling step in which a charged, preferably soluble, polymer having pendant zwitterionic groups is introduced in the form of a composition in which it is soluble and is gelled by being mixed with a counterionically charged soluble polymer (polyelectrolyte), to form a polyion complex. Preferably the or each soluble polymer is formed by polymerizing ethylenically unsatured monomers including a zwitterionic monomer, for instance 2-methacryloyloxyethyl-2′-trimethylammoniumethyl phosphate inner salt, an ionic monomer such as trimethylammonium alkyl(alk)acrylate or a sulphoalkyl(alk)acrylate and optionally a diluent monomer such as an alkyl(alk)acrylate.

Abstract: A polyion complex (PIC) is formed of an anionic soluble polymer formed from ethylenically unsaturated monomers including at least one anionic or monomer and a cationic soluble polymer formed from ethylenically unsaturated monomer including at least one cationic monomer, in which the monomers used to form at least one of the polymers comprise a zwitterionic monomer and in which the monomers used to form at least one of the polymers include non-ionic monomer, preferably C1-24 alkyl(meth)acrylate, in which the overall ratio of anionic groups to cationic groups in the PIC is in the range 1.5:1 to 1:1.5, and in which the polymers are combined in ratios to provide a PIC in which there are units derived from zwitterionic monomer in an amount in the range 1 to 70 mole % based on total monomer derived units in the PIC and there are units derived from non-ionic monomer in an amount in the range 0 to 60 mole % based on total monomer derived units in the PIC. The PIC is preferably swollen in water and is a flowable gel.