摘要:
In accordance with the present invention, there is provided a process for producing a polymer by a living radical polymerization method which is also applicable to the polymerization of a methacrylate monomer, and a methacrylate-based polymer having a narrow molecular weight distribution which is produced by the above process. Specifically, the present invention relates to a process for producing a methacrylate-based polymer by a atom transfer radical polymerization method in which a polymerizable monomer containing at least one methacrylate monomer is polymerized in the presence of a redox catalyst comprising a metal complex containing at least one transition metal as a central metal selected from the group consisting of elements of Groups 7 to 11 of the Periodic Table, using an organohalogen compound or a halogenated sulfonyl compound as a polymerization initiator.
摘要:
A composition for delivery of a therapeutic agent is provided. The composition comprises: (a) a biocompatible block copolymer comprising one or more elastomeric blocks and one or more thermoplastic blocks and (b) a therapeutic agent, wherein the block copolymer is loaded with the therapeutic agent. The block copolymer is preferably of the formula X-(AB)n, where A is an elastomeric block, B is a thermoplastic block, n is a positive whole number and X is a seed molecule. The elastomeric blocks are preferably polyolefin blocks, and the thermoplastic blocks are preferably selected from vinyl aromatic blocks and methacrylate blocks. According to another aspect of the invention, a medical device is provided, at least a portion of which is insertable or implantable into the body of a patient. The medical device comprises (a) the above biocompatible block copolymer and (b) a therapeutic agent, wherein the block copolymer is loaded with the therapeutic agent. According to another aspect of the present invention, a method of treatment is provided in which the above device is implanted or inserted into a patient, resulting in the release of therapeutic agent in the patient over an extended period. According to yet another aspect of the invention, a coated medical device is provided which comprises: (a) an intravascular or intervascular medical device and (b) a coating over at least a portion of the intravascular or intervascular a medical device, wherein the coating comprises the above biocompatible block copolymer.
摘要:
Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.
摘要:
A protective coating composition in an organic liquid carrier comrpising a polymeric film forming binder, the polymeric binder comprising by weight: (a) 50% to 100% of an epoxy-polyester block copolymer being the reaction product of a preformed epoxy resin and a preformed carboxyl functional, and (b) 0 to 50% of a crosslinker where the sum of (a) and (b) is 100%, characterised in that the carboxyl functional polyester prepolymer is the reaction product of one or more polyols with one or more dicarboxylic acids or their anhydrides, where the dicarboxylic acids or anhydrides comprise a mixture of (i) 20% to 45% of an aromatic dicarboxylic acid or its anhydride, (ii) 55% to 80% of cyclohexane dicarboxylic acid, and (iii) 0 to 10% other aliphatic dicarboxylic acid, where the sum of (i), (ii), and (iii) is 100% based on the weight of the dicarboxylic acid and anhydride components.
摘要:
A process provides a ceramic film, such as a mesoporous silica film, on a substrate, such as a silicon wafer. The process includes preparing a film-forming fluid containing a ceramic precursor, a catalyst, a surfactant and a solvent, depositing the film-forming fluid on the substrate, and removing the solvent from the film-forming fluid on the substrate to produce the ceramic film on the substrate. The ceramic film has a dielectric constant below 2.3, a halide content of less than 1 ppm and a metal content of less than 500 ppm, making it useful for current and future microelectronics applications.
摘要:
A composition for delivery of a therapeutic agent is provided. The composition comprises: (a) a biocompatible block copolymer comprising one or more elastomeric blocks and one or more thermoplastic blocks and (b) a therapeutic agent, wherein the block copolymer is loaded with the therapeutic agent. The block copolymer is preferably of the formula X—(AB)n, where A is an elastomeric block, B is a thermoplastic block, n is a positive whole number and X is a seed molecule. The elastomeric blocks are preferably polyolefin blocks, and the thermoplastic blocks are preferably selected from vinyl aromatic blocks and methacrylate blocks. According to another aspect of the invention, a medical device is provided, at least a portion of which is insertable or implantable into the body of a patient. The medical device comprises (a) the above biocompatible block copolymer and (b) a therapeutic agent, wherein the block copolymer is loaded with the therapeutic agent. According to another aspect of the present invention, a method of treatment is provided in which the above device is implanted or inserted into a patient, resulting in the release of therapeutic agent in the patient over an extended period. According to yet another aspect of the invention, a coated medical device is provided which comprises: (a) an intravascular or intervascular medical device and (b) a coating over at least a portion of the intravascular or intervascular a medical device, wherein the coating comprises the above biocompatible block copolymer.
摘要:
A (meth)acrylate terpolymer comprising 1-30% of total terpolymer weight epoxy-functional (meth)acrylate monomer units, 1-98% of total terpolymer weight tackifier (meth)acrylate monomer units, and 1-98% of total terpolymer weight compatibilizing (meth)acrylate monomer units, wherein the compatibilizing (meth)acrylate monomer unit is a (meth)acrylic ester derived from an aromatic alcohol containing 6-14 carbon atoms. Also provided are self-fixturing adhesive compositions comprising the acrylate terpolymer of the present invention and methods of their use.
摘要:
An antireflection film and method of making same includes a substrate having a first surface and a second surface, an inorganic layer deposited on the first surface of the substrate, and an optically active polymer layer formed by curing a curable composition in situ on the inorganic layer, the polymer layer having a refractive index not greater than about 1.53 over the wavelength range of 400 nm to 700 nm and a thickness of from about 20 nm to about 200 nm, and an adhesive layer deposited on the second surface of the substrate.
摘要:
A thermosetting composition comprising a co-reactable solid, particulate mixture of (a) capped polyisocyanate crosslinking agent, e.g., a trimer of 1-isocyanato-3,3,5 -trimethyl-5-isocyanatomethylcyclohexane capped with e-caprolactam or 1H-2,5-dimethyl pyrazole, and (b) hydroxy functional polymer, is described. The hydroxy functional polymer is prepared by atom transfer radical polymerization and has well defined polymer chain architecture and polydispersity index of less than 2.5. The thermosetting compositions of the present invention have utility as powder coatings compositions.
摘要:
A substantially non-gelled polymeric composition is disclosed and comprises the reaction product of an A polymer which is an addition polymer having 3.5 or more reactive functional groups per polymer chain and a B polymer having about 2 to about 3 functional groups per polymer chain that are co-reactive with the reactive functional groups of the A polymer. Also disclosed is a process for preparing such polymeric compositions, powder coatings and 100% solids ink resins prepared with such polymeric compositions, and a method for deglossing a powder coating using such polymeric compositions.