Abstract: The present subject matter relates generally to polymer compositions, and more particularly to irradiated polymer compositions comprising at least one non-phenolic stabilizer. The present polymer compositions comprise an unexpected balance of properties after being subjected to irradiation treatments, including an unexpected combination of a lower melt flow rate ratio (MFRr) and high melt tension after being irradiated, while minimizing negative yellowing effects.

Abstract: The present subject matter relates to processes for irradiating visbroken propylene polymer compositions or extrudates of propylene polymer compositions containing a propylene polymer having a low polydispersity index and a non-phenolic stabilizer.

Abstract: There is provided a method for preparing a plumbing manifold for use in a water system in which the manifold after molding is subjected to cross-linking high energy radiation. The manifold is made by polyethylene or a metallocene polyethylene.

Abstract: The present invention relates to processes for preparing actinic-radiation-curable and/or dual-cure poly(meth)acrylates by preparing a poly(meth)acrylate containing hydroxy-functional side chains and transesterifying or esterifying the poly(meth)acrylate containing hydroxy-functional side chains with a (meth)acrylate or (meth)acrylic acid. The present invention further relates to the actinic-radiation-curable and/or dual-cure poly(meth)acrylates themselves and to the use of the actinic-radiation-curable and/or dual-cure poly(meth)acrylates in the preparation of dispersions or as a component in coating formulations and topcoats comprising at least one actinic-radiation-curable and/or dual-cure poly(meth)acrylate.

Abstract: A 1,4-di-substituted diacetylene polymer that is soluble in organic solvent, is composed of a repeating unit represented by the general formula ?CR—C?C—CR?? (wherein, R and R? represent identical or different monovalent organic substituents), and has an average degree of polymerization of 4 to 200 and a ratio (Mw/Mn) of weight average molecular weight (Mw) to number average molecular weight corresponding to said average degree of polymerization (Mn) of 1.1 to 5.0, and a process for producing the 1,4-di-substituted diacetylene polymer by irradiating a solution of the soluble 1,4-di-substituted diacetylene polymer with laser light having a wavelength within the range of 250 to 1,200 nm, and preferably 550 to 900 nm, to cause a photodegradation reaction of said polymer, or heating a solution of the soluble 1,4-di-substituted diacetylene polymer to a temperature of 100 to 300° C.

Abstract: A polymerization process with elevated productivity using a coordination catalyst, wherein electromagnetic radiation is applied during polymerization. The irradiation of light greatly increases the activity of the coordination catalyst.

Abstract: The invention provides a sterile medical implant or medical implant part comprising ultrahigh molecular weight polyethylene that has a molecular weight of about 400,000 atomic mass units or more. The invention also provides methods for producing, using, and preparing a medical implant or medical implant part, which comprise contacting the medical implant or medical implant part with water, such that the weight of the ultrahigh molecular weight polyethylene is increased, and the wear performance of the medical implant or medical implant part desirably is enhanced.

Abstract: A method is provided for forming a plastic prosthesis bearing, net-shape bearing, near net-shape bearing or plastic stock from which such a bearing can be formed. The method includes the steps of providing plastic resin in powdered form, subjecting the powdered resin to irradiation to cross-link the resin, and molding the irradiated powder. The irradiated powder is molded by applying heat and pressure to form the powder into a desired solid plastic shape, the heating being sufficient to melt the powder.

Abstract: A medical implant of ultrahigh molecular weight polyethylene having an improved balance of wear properties and oxidation resistance is prepared by irradiating a preform of ultrahigh molecular weight polyethylene, annealing the irradiated preform in the absence of oxygen to a temperature at or above the onset of melting temperature, and forming an implant from the stabilized cross-linked polymer. Implants prepared according to the process of the present invention have comparable oxidation resistance and superior wear performance compared to unirradiated ultrahigh molecular weight polyethylene.

Abstract: To provide a transparent resin which is suitable in the process of producing a coating for electronic materials, a glass having both of the scattering-preventing function and the antireflective function, an adhesive agent, a shock-absorbing material, an ultraviolet-cutting sheet for televisions, a filter for VDTs and a high refractive index primer composition as well as the process for the production of primer-coated lenses using said primer composition, is excellent in a coatability, adhesive property, storage stability, durability, shock resistance and the like, and is particularly excellent in a transparency and adhesive property after curing of the same. A transparent resin having an adhesive property characterized by comprising a cured product of the polymerizing composition which comprises at least one of diallyl phthalate, diallyl isophthalate and diallyl terephthalate, and pentaerythritol tetra (3-mercaptopropionate).

Abstract: A medical implant of ultrahigh molecular weight polyethylene having an improved balance of wear properties and oxidation resistance is prepared by irradiating a preform of ultrahigh molecular weight polyethylene, annealing the irradiated preform in the absence of oxygen to a temperature at or above the onset of melting temperature, and forming an implant from the stabilized cross-linked polymer. Implants prepared according to the process of the present invention have comparable oxidation resistance and superior wear performance compared to unirradiated ultrahigh molecular weight polyethylene.

Abstract: A medical implant of ultrahigh molecular weight polyethylene having an improved balance of wear properties and oxidation resistance is prepared by irradiating a preform of ultrahigh molecular weight polyethylene, annealing the irradiated preform in the absence of oxygen to a temperature at or above the onset of melting temperature, and forming an implant from the stabilized cross-linked polymer. Implants prepared according to the process of the present invention have comparable oxidation resistance and superior wear performance compared to unirradiated ultrahigh molecular weight polyethylene.

Abstract: Fibers as a reinforcing substrate are impregnated with the particles of polytetrafluoroethylene and pressed into a shape at the melting point of polytetrafluoroethylene. Alternatively, the reinforcing substrate sandwiched between polytetrafluoroethylene sheets is pressed into a shape at the melting point of polytetrafluoroethylene. In either case, the shaped article is then exposed to an ionizing radiation in an oxygen-free atmosphere at the melting point of polytetrafluoroethylene. The inherent characteristics of the polytetrafluoroethylene, i.e., heat resistance, chemical resistance, abrasion resistance and lubricity, are retained and yet radiation resistance and resin transparency are imparted.

Abstract: Wear resistance and oxidation resistance of polymer material or a polymer component for bioimplantation are improved by packaging a polymer object in a sealed gas impermeable package substantially free of oxygen, irradiating the package with penetrating radiation to an extent sufficient to effect a desired substantial level of cross-linking within the polymer, and warming the packaged object while maintaining an elevated hydrostatic pressure to cause gases released during irradiation to recombine, stabilizing the material against subsequent oxidative change. The pressure stabilization terminates active sites, substantially eliminating free radicals. When applied to finished parts, the process simultaneously hardens and sterilizes the parts without degrading mechanical properties or dimensions. When applied to bulk material or unfinished parts, the part may be subsequent machined or otherwise finished, and sterilized by any conventional means.

Abstract: A medical implant of ultrahigh molecular weight polyethylene having an improved balance of wear properties and oxidation resistance is prepared by irradiating a preform of ultrahigh molecular weight polyethylene, annealing the irradiated preform in the absence of oxygen to a temperature at or above the onset of melting temperature, and forming an implant from the stabilized cross-linked polymer. Implants prepared according to the process of the present invention have comparable oxidation resistance and superior wear performance compared to unirradiated ultrahigh molecular weight polyethylene.

Abstract: Polypropylene mixtures of increased stress-crack resistance and melt strength can be produced by irradiating polypropylene powders with low average particle diameters by low energy electron-beam accelerators with energies of 150 to 300 keV. The polypropylene mixtures produced are suitable particularly for producing films, sheets, panels, coatings, pipes, hollow objects and foamed materials.

Abstract: Multiconstituent fibers prepared from two or more polymers, with at least one of these polymers being randomly dispersed through the fiber, in the form of domains. At least about 40 percent by weight of these domains have one length of at least 20 microns, measured in the direction along the fiber axis, and have another length, measured along the longest line dissecting the domain cross-section in a plane perpendicular to the fiber axis, of at least about 5 percent of the fiber equivalent diameter.

Abstract: Multiconstituent fibers having a dominant continuous linear low density polyethylene phase, and one or more discontinuous phase polymers, dispersed through the dominant continuous phase in the form of domains. The indicated discontinuous phases polymers are chosen from among polypropylene and poly(propylene-co-ethylene) copolymers.

Abstract: A hydrophilic, pressure-sensitive adhesive composition prepared by irradiating solid poly(N-vinyl lactam) with ionizing radiation to crosslink the poly(N-vinyl lactam) and thereafter mixing the radiation-crosslinked poly(N-vinyl lactam) with essentially unirradiated plasticizer in an amount sufficient to form a cohesive, pressure-sensitive adhesive composition. The composition is useful as a biomedical adhesive for transmitting or receiving electrical signals as a component of a biomedical electrode. The composition is also useful as a drug delivery device to deliver pharmaceuticals or other active ingredients to or through mammalian skin. The composition is also useful as a component in a skin covering for protecting mammalian skin Or mammalian skin openings with antimicrobial agents. A method of preparation of the composition is also disclosed.

Abstract: A method for modifying the plastic surface of an article adapted for contacting living tissue by the gamma or electron beam irradiation induced chemical graft coating thereon of:(1) a neutral or ionic water-soluble, hydrophilic vinylic monomer or salt thereof;(2) a mixture of at least two of said monomers, or(3) a mixture of (1) or (2) with up to about 50%, by weight, based on the total monomer weight, of a member selected from the group consisting of N-vinylpyrrolidone, 2-hydroxyethyl-methacrylate, and mixtures thereof; so as to form a hydrophilic graft polymer coating on the surface.

Abstract: A process for producing a slow-release powder which permit various active ingredients such as perfumes, insect control agents, rust inhibitors, mold inhibitors and antibacterial agents to be slowly released over a prolonged time, the process comprising the steps of mixing a long-chain compound with the ingredients, mixing the resulting mixture with urea, and exposing the resulting urea adduct to radiation.

Abstract: A copolymer of trans-1,4-hexadiene and propylene, and a method for its preparation. The copolymer is isotactic, essentially free of cis-1,4-hexadiene, and contains from 0.01 to 5 mole percent 1,4-hexadiene. The copolymer is radiation-stabilized against molecular weight degradation, and cross-links to form gel upon exposure to radiation. The copolymer is prepared by contacting a mixture of propylene and 1,4-hexadiene essentially free of cis-1,4-hexadiene with a coordination catlyst, e.g. Ziegler-Natta catalyst, under copolymerization conditions. Hydrogen is used to moderate the molecular weight of the copolymer and enhance the catalyst activity.

Abstract: A process and apparatus are disclosed for producing polymerized beads containing actives such as perfumes and pesticides, by forming droplets from a solution of monomers and the actives. The solution is subjected to ultraviolet light to initiate polymerization. The droplets are caused to fall through a reaction vessel as polymerization continues so as to polymerize substantially spherical beads containing the actives. In one embodiment, the droplets are irradiated as they fall through the reaction vessel. In a second embodiment, the solution is irradiated prior to droplet formation and the fall. The beads are collected and can be cured if necessary. The process is preferably performed in an inert gas environment which most preferably is nitrogen. A nitrogen stream can serve as a carrier for the monomers and active ingredients. The nitrogen environment is maintained in the reaction vessel, and in the curing structure, if present.

Abstract: Acrylate-based pressure-sensitive adhesives are produced by a process in which a liquid, polymerizable monomer composition containing at least one acrylate monomer is placed in a closed reaction vessel, deaerated and the monomer(s) are polymerized by exposure to ionizing radiation such as gamma irradiation. The process allows for the direct production of low-solvent or solventless acrylate-based adhesives suitable for application by hot-melt techniques.

Abstract: A method of reducing the monomer content of a polymer or polymerization media comprising subjecting the polymer containing the monomer to sufficient irradiation with a high energy radiation to polymerize said monomer, said radiation preferably occurring in presence of chemical agent that accelerate the rate of consumption of the undesirable monomer, i.e. the monomer considered hazardous and/or protects the polymer from radiation degradation.