Abstract: The invention relates to metal oxide or semimetal oxide nanoparticles having an average particle size of from 2 to 250 nm, characterized in that the nanoparticles have at least two different, free-radically polymerizable groups on the surface. The invention further relates to nanocomposites produced from such nanoparticles and also processes for producing them.

Abstract: A bioactive PMMA (polymethylmethacrylate) bone cement contains a powder component and a reactive monomer liquid, wherein the powder component and the reactive monomer liquid when mixed with one another react with one another and form a polymer-based solid material. The powder component contains particulate polymer powder of polymethylmethacrylates; a radical starter; and anionic copolymer nanoparticles. The anionic copolymer nanoparticles are distributed in nano-particulate form within the particulate powder component or coated as a film on particles of the particulate polymer powder.

Abstract: The invention relates to a method for producing hybrid-particles containing polymer and SiO2-particles, wherein a) in a first polymerization step in aqueous medium a water-insoluble phase containing one or more monomeric and colloidal SiO2-particles having an average particle diameter of 1 to 150 nm are polymerized, and b) in a second polymerization step in aqueous medium one or more monomers are polymerized in the presence of the polymer obtained in the first polymerization step.

Abstract: The invention provides a polymerizable composition which comprises: a) acrylates and/or methacrylates, b) 0.05% to 70% by weight of SiO2 particles having an average particle size of 1 to 30 nm which have polymerizable groups of the methacryloyl, acryloyl, styryl, itaconyl, crotonyl, vinyl, allyl and/or alkenyl type on the surface and are present in dispersion in the acrylates and/or methacrylates, at least 50% of the SiO2 particles consisting of individual, unaggregated or unagglomerated primary particles, c) not more than 2% by weight of crosslinker molecules.

Abstract: The invention relates to a polymerizable composition containing: a) acrylates and/or methacrylates which have a glass transition temperature Tg of 0° C. or less, b) from 0.5 to 70% by weight of SiO2 particles which have an average particle size of from 1 to 150 nm and have polymerizable groups on the surface and are present in dispersed form in the acrylates and/or methacrylates, with at least 50% of the SiO2 particles being individual unaggregated or unagglomerated primary particles, where the composition contains not more than 2% by weight of crosslinker molecules.

Abstract: Subject of the invention is a hybrid particle comprising at least two vinyl polymers (vinyl polymers A and B), wherein vinyl polymer A comprises colloidal SiO2 particles with an average particle size from 1 to 150 nm and vinyl polymer B is capable of crosslinking hybrid particles to one another.

Abstract: The invention relates to a method for producing hybrid-particles containing polymer and SiO2-particles, wherein a) in a first polymerization step in aqueous medium a water-insoluble phase containing one or more monomeric and colloidal SiO2-particles having an average particle diameter of 1 to 150 nm are polymerized, and b) in a second polymerization step in aqueous medium one or more monomers are polymerized in the presence of the polymer obtained in the first polymerization step.

Abstract: The invention relates to hydrogels containing water and polyethylene glycol-dimethacrylates in a polymerized form. The polymethacrylate blocks are so short that they form no proper phase. The invention further relates to methods for producing said hydrogels. The inventive hydrogels are provided with reduced haze and are used as materials for contact lenses, electrophoresis gels, membrane materials, and sound-absorbing materials.

Abstract: The invention relates to a polymerizable composition containing: a) acrylates and/or methacrylates which have a glass transition temperature Tg of 0° C. or less, b) from 0.5 to 70% by weight of SiO2 particles which have an average particle size of from 1 to 150 nm and have polymerizable groups on the surface and are present in dispersed form in the acrylates and/or methacrylates, with at least 50% of the SiO2 particles being individual unaggregated or unagglomerated primary particles, where the composition contains not more than 2% by weight of crosslinker molecules.

Abstract: The invention provides a polymerizable composition which comprises: a) acrylates and/or methacrylates, b) 0.05% to 70% by weight of SiO2 particles having an average particle size of 1 to 30 nm which have polymerizable groups of the methacryloyl, acryloyl, styryl, itaconyl, crotonyl, vinyl, allyl and/or alkenyl type on the surface and are present in dispersion in the acrylates and/or methacrylates, at least 50% of the SiO2 particles consisting of individual, unaggregated or unagglomerated primary particles, c) not more than 2% by weight of crosslinker molecules.

Abstract: The invention relates to metal oxide or semimetal oxide nanoparticles having an average particle size of from 2 to 250 nm, characterized in that the nanoparticles have at least two different, free-radically polymerizable groups on the surface. The invention further relates to nanocomposites produced from such nanoparticles and also processes for producing them.

Abstract: A bioactive PMMA (polymethylmethacrylate) bone cement contains a powder component and a reactive monomer liquid, wherein the powder component and the reactive monomer liquid when mixed with one another react with one another and form a polymer-based solid material. The powder component contains particulate polymer powder of polymethylmethacrylates; a radical starter; and anionic copolymer nanoparticles. The anionic copolymer nanoparticles are distributed in nano-particulate form within the particulate powder component or coated as a film on particles of the particulate polymer powder.

Abstract: The invention relates to mouldings comprising a transparent plastic matrix with small proportions of incorporated, very finely divided plastic particles which have a particle diameter less than the wavelength of visible light, and to the use of these mouldings for visualizing laser beams and for illumination purposes. A refractive index difference between the core of the scattering particles B and the matrix plastic A in the range 0.09-0.3 and a good distribution of the plastic particles B in the matrix are important for high transparency of the mouldings according to the invention in combination with good visualization of laser beams. The plastic particles B are core-shell particles, as are readily obtainable by emulsion polymerization (cf. for example DE 198 20 302).

Abstract: The invention relates to active ingredient-containing polymer particles comprising a vinyl polymer from 10-80% by weight monomers comprising amino and/or carboxyl groups, which is insoluble in one part of the pH range 0-10 and is soluble in another part of the range, wherein these active ingredient-containing polymer particles comprise 3-1000 parts of active ingredient per part of vinyl polymer, have a particle size in the range 20 nm-8 ?m and the vinyl polymer is >50% by weight composed of polymers having a molecular weight of <100 000 daltons.

Abstract: The invention relates to polymer networks comprising dimethacrylates of formula CH2?CCH3COO—X—O—COCCH3?CH2 and thiols as main components, X representing a bifunctional radical. Said dimethacrylate/modifier networks represent materials whose properties are determined essentially by the properties of the X group as a result of the very short polymethacrylate blocks used. The networks are very soft and flexible or highly solid, tough, and solvent-resistant depending on the type of the X group that is used.

Abstract: The invention relates to hydrogels containing water and polyethylene glycol-dimethacrylates in a polymerized form. The polymethacrylate blocks are so short that they form no proper phase. The invention further relates to methods for producing said hydrogels. The inventive hydrogels are provided with reduced haze and are used as materials for contact lenses, electrophoresis gels, membrane materials, and sound-absorbing materials.

Abstract: Asymmetric (meth)acrylate crosslinking agents may be prepared by reacting a hydroxyacrylate with methacrylic anhydride to give a crosslinking agent with acrylic and methacrylic groups. Asymmetric (meth)acrylate crosslinking agents can be employed in the production of superabsorbers and thickening agents.

Abstract: The invention describes polyesters containing (meth)acrylate end groups, of the general formula (I) CH2═CRCOO—PE—OCOCR═CH2 where R=CH3 or H, where PE=[—A—OCO—B—COO—]m—A—, [—CHR′—COO—]n—A—[—OCOCHR′—]n, or combinations thereof, in which A is an alkylidene radical having 2-20 carbon atoms or an alkoxylidene radical having 2-1000, preferably 2-500, alkoxylidene units, B is a saturated alkylidene radical having 2-10 carbon atoms, R′ is H or CH3, m is 1-100, n is 1-100, and, if both m and n are present, the sum m+n is 2-200, where the polyesters containing (meth)acrylate end groups are characterized in that a) the content of short-chain di(meth)acrylates (II) CH2═CRCOO—A—OCOCR═CH2 is <5% by weight, b) the content of hydroxyl groups is <0.25 mol/mol of (meth)acrylate, and c) the APHA color number is <200.

Abstract: The invention describes polyesters containing (meth)acrylate end groups, of the general formula (I) CH2═CRCOO—PE—OCOCR═CH2 where R=CH3 or H, where PE=[—A—OCO—B—COO—]m—A—, [—CHR′—COO—]n—A—[—OCOCHR′—]n, or combinations thereof, in which A is an alkylidene radical having 2-20 carbon atoms or an alkoxylidene radical having 2-1000, preferably 2-500, alkoxylidene units, B is a saturated alkylidene radical having 2-10 carbon atoms, R′ is H or CH3, m is 1-100, n is 1-100, and, if both m and n are present, the sum m+n is 2-200, where the polyesters containing (meth)acrylate end groups are characterised in that a) the content of short-chain di(meth)acrylates (II) CH2═CRCOO—A—OCOCR═CH2 is <5% by weight, b) the content of hydroxyl groups is <0.25 mol/mol of (meth)acrylate, and c) the APHA color number is <200.

Abstract: Asymmetric (meth)acrylate crosslinking agents may be prepared by reacting a hydroxyacrylate with methacrylic anhydride to give a crosslinking agent with acrylic and methacrylic groups. Asymmetric (meth)acrylate crosslinking agents can be employed in the production of superabsorbers and thickening agents.