105 results about "Pre irradiation" patented technology

The invention provides methods and compositions for providing biocompatible surfaces to medical articles. In particular the invention provides biocompatible coatings with heparin activity. In some aspects, the biocompatible coatings of the invention are able to release a bioactive agent. The coatings can be formed using biostable or biodegradable polymeric material and photoreactive groups. The invention also provides methods for improving the quality of bioactive agent-containing coatings by performing pre-irradiation of biocompatible coating compositions.

The invention relates to an antibacterial treatment method for wool fiber, which comprises the following steps: an organic-inorganic composite antibacterial agent, namely silver-bearing silicon dioxide-chitosan is taken as an antibacterial agent and prepared into a pentabasic antibacterial mother liquor with anhydrous alcohol, deionized water, a diluted hydrochloric acid, a dispering/coupling agent and gamma-vinyltriethoxysilane A-151; the wool fiber is subjected to pre-irradiation of the ultraviolet light, and then immersed into the antibacterial mother liquor for secondary irradiation; and the wool fiber and the silver-bearing silicon dioxide-chitosan composite antibacterial agent generate chemical reaction under the action of a light trigger benzophenone and are combined by means of valence linkage to form an antibacterial film with the thickness of 200 nanometers. The antibacterial treatment method improves the persistence of antibacterial functions of the wool fiber, and the antibacterial rate of the wool fiber is still 98.6 percent after being washed for 50 times. Moreover, the antibacterial treatment method has short process flow, small number of equipment used, quick antibacterial speed, high efficiency and good effect, is easy to prepare the mother liquor, is particularly suitable for performing antibacterial treatment on the wool fiber and pashm fiber, and improves the efficiency by 90 percent compared with the prior antibacterial technology.

The present invention relates to a high strength hydrogel and a preparation method thereof. The method is firstly to perform a pre-irradiation and peroxidation process and then a thermal-initiated polymerization process. The pre-irradiation and peroxidation process is to irradiate the water soluble polymer or the water soluble polymer solution in the nitrogen atmosphere by the high energy radiation source to combine the peroxy group on the polymer chains; and the thermal-initiated polymerization process is to mix solution prepared by the water soluble polymer after initiated with the water soluble monomer or mix the water soluble polymer solution after initiated with the water soluble monomer, and then the product is obtained by deoxidizing and heating the mixture. The preparation method of hydrogel of the invention is simple, and the prepared hydrogel has a high mechanical strength, a wide selecting range of the raw materials, and a high applied cost.

The preparation process of functional polyolefin resin includes electronic beam or gamma-ray pre-irradiation treatment of functional polyolefin resin; mechanical mixing of polyolefin resin after pre-treatment, functional monomer and electron donor reagent; and reacting extrusion for the polyolefin resin in molten state and functional monomer to produce grafting reaction. The polyolefin resin includes polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-styrene copolymer, polystyrene, etc; the functional monomer is unsaturated organic acid or its derivative with amino group, isocyanate, hydroxyl group or other reactive functional group; and the electron donor reagent includes electron-rich compound with P, N, S or O element, p-benzoquinone, triphenyl phosphite, triphenyl phosphate, etc.

A method of selecting suitable laser-stable optical material for making an optical element, especially for transmission at wavelengths under 200 nm, is described. It includes a first pre-irradiation to produce radiation damage, subsequent excitation of induced fluorescence with light at between 350 to 700 nm at least ten minutes after the first pre-irradiation and measurement of induced fluorescence intensities at one or more wavelengths between 550 nm and 810 nm. After the fluorescence intensity measurement a second pre-irradiation is performed with an at least 1000-fold higher energy than in the first pre-irradiation and then induced fluorescence intensities are again measured to determine the increase in the fluorescence intensities. The materials determined to have suitable laser stability are used for making lenses, prisms, light-conducting rods, optical windows and optical devices for DUV lithography, especially steppers and excimer lasers, integrated circuits, computer chips as well as other electronic devices.

The invention relates to a method for testing the influence of total dose irradiation on the PMOSFET negative bias temperature instability. The method includes test sample grouping and test parameterselection; the total dose irradiation and annealing tests of the test sample; and the negative bias temperature instability measurement of the test sample. In order to ensure the consistency and accuracy of the test result, the sample is divided into a pre-irradiation group, a comparison group and two pre-test groups, and on the basis of the pre-test, the total dose irradiation and annealing testsare carried out on the pre-irradiation group under the determination condition, the comparison group and the pre-irradiation group are subjected to a negative bias temperature instability test underthe same condition, and the test result is compared, the influence of the total dose irradiation on the negative bias temperature instability of the sample is obtained. The method provided by the invention can represent the influence of the total dose irradiation on the negative bias temperature instability of a P-channel metal oxide semiconductor field effect transistor.

The invention provides a process for preparing irradiation modified olefinic thermoplastic elastomer blend resin and its use, wherein the preparing process carrying out pre-irradiation treatment to the olefinic thermoplastic elastomer blend resin through gamma-rays or electron beams, then subjecting the resin to further cross-linking reaction in molten condition. The obtained resin comprises 50-90% of ethylene-alpha-olefin copolymer, and 10-50% of ethylene-mono-substituted alpha-olefin copolymer.

The invention relates to a method for preparing ion exchange fiber materials. The method takes fibers such as polytetrafluoroethylene, polypropylene, polyacrylonitrile and polyvinyl alcohol which still have good stability and integrity in an extreme environment as a substrate, prepares the strong-acid and weak-acid bifunctional ion exchange fiber materials by pre-irradiation grafting, and provides products with more superior performance for application (such as purification of strong acid reagent and strong alkali reagent) of the ion exchange fiber materials under harsh conditions. The static adsorption capacity of the products can be controlled to be between 3.0 and 4.98 mmol/g, wherein the static adsorption capacity of strong acid parts is between 1.85 and 2.57 mmol/g. The method has high pre-irradiation grafting efficiency, avoids huge waste of monomers in mutual irradiation, can make the grafting ratio realize controllable operation, avoid utilization of strong corrosive materials such as concentrated sulfuric acid and chlorosulfonic acid for sulfonation reaction, avoid environmental pollution and equipment corrosion, has simple process and easy operation, and provides favorable conditions for industrialization of the ion exchange fiber materials.

The invention provides functionalized polypropylene (PP) for flexible packages and a preparation method thereof. The functionalized PP for flexible packages comprises the following components: (a) 30to 70 weight parts of irradiated PP powder; (b) 30 to 70 weight parts of non-irradiated PP powder; and (c) 0.4 to 15 weight parts of polar co-monomer formed by subjecting the irradiated PP powder in component (a) and the non-irradiated PP powder in component (b) to graft copolymerization, and optionally comprising (d) antioxidant and/or lubricant, wherein, the PP powder in component (a) is irradiated in the protective presence of nitrogen with the irradiation source thereof being a cobalt source, the irradiation dose thereof being 20kGy to 60kGy, and the dose rate thereof being 2 to 0.5 kGf/h.The invention intends to prepare PP with higher polarity and improve the print and compound properties of PP films by grafting the polar monomer of glycidyl methacrylate (GMA) and styrene on PP powder on the basis of the pre-irradiation method.

The invention relates to a polyethylene-polystyrene resin and a preparation method thereof. The preparation method comprises the following steps of: performing pre-irradiation treatment on polyethylene resin by using beta rays or gamma rays; adding the polyethylene resin after the pre-irradiation treatment, a dispersing agent, a functional monomer, an emulsifying agent, a nucleating agent and a homopolymerization inhibiting agent into a reactor to perform suspension graft polymerization reaction for a certain period of time at a certain temperature; and filtering, washing and drying a suspension graft product to obtain the polyethylene-polystyrene resin. The concentrations of macromolecular peroxides generated by the pre-irradiation are distributed evenly, so side reactions such as monomer homopolymerization, polymer crosslinking and/or degradation and the like caused by a micromolecule chemical initiator are avoided; the percent grafting ratio reaches 21 to 42 percent; the homopolymerization inhibiting agent reduces the homopolymerization of the monomer in the suspension grafting process; and the polyethylene-polystyrene resin has the tensile strength of more than 22 MPa, breaking elongation of over 90 percent and elastic modulus of more than 480 MPa, and has good mechanical properties such as strength, tenacity, impact strength and the like.

The invention proposes a novel method for generating a nano educt by using ion pre-irradiation, so as to improve the anti-irradiation properties of a material. The method comprises the following steps: carrying out proper pre-irradiation on low activation ferritic/martensitic steel or low activation model alloy; and forming a nanophase in the material. The stable size and structure of the nano precipitate can be kept in subsequent irradiation, and more point defect traps are provided for the material. Thus, the anti-irradiation properties of the low activation material are improved.

The invention discloses a polypropylene industrial yarn cloth grafting modification method. Pre-impregnating treatment and pre-irradiation treatment are performed to form a number of polar benzhydrol free radicals with high stability on the surfaces of fibers and inside the fibers, a small quantity of nonpolar polypropylene macromolecular chain free radicals with poor stability are replaced, and the adsorption and graft polymerization of monomers such as acrylic acid/sodium are facilitated. Sodium hydroxide is used for neutralizing acrylic monomers under electrostatic interaction of ions, so that the solubility of the monomers and the grafting macromolecular chain in a grafting solution is improved, the hydrodynamic volume of the macromolecular chain is increased, and the adsorption and graft modification of the monomers in the grafting chain are facilitated. According to the grafting modification method, the hydrophilcity, the dyeing property and the adsorption separation property of the polypropylene monofilament fabric can be achieved, and the grafting modified industrial yarn cloth can be widely applied to adsorption separation treatment of dye wastewater and heavy metal ion wastewater.

The invention relates to a polypropylene blend and a preparation method of the polypropylene blend, in particular to a high-melt-strength polypropylene blend and a preparation method of the high-melt-strength polypropylene blend. The high-melt-strength polypropylene blend and the preparation method of the high-melt-strength polypropylene blend aim to solve the problems that an existing high-melt-strength polypropylene blend and a preparation method of the existing high-melt-strength polypropylene blend are high in energy consumption, low in freeze-drying efficiency and grafting efficiency and free of recovering a generated PP degradation broken link. The high-melt-strength polypropylene blend is formed by polypropylene powder, pre-irradiation polypropylene powder, pre-irradiation vulcanized rubber powder, monomer assistants and heat stabilizers in a melt blending mode. The preparation method includes the first step of preparing the pre-irradiation polypropylene powder, the second step of preparing the pre-irradiation vulcanized rubber powder and the third step of preparing the high-melt-strength polypropylene blend. The freeze-drying efficiency is improved, energy consumption is reduced, and the drying efficiency is improved. The use amount of the rubber powder is decreased to 1%-20%, so that the modification cost is lowered; the grafting efficiency is improved by more than one time; the monomer assistants are added, the service life of the active centre is prolonged, and the PP degradation broken link is effectively restrained.

The present invention relates to a preparation method and uses of a composite hydrogel containing hydroxyapatite (HAP) nanoparticles, wherein an inorganic component in the composite hydrogel is HAP nanoparticles prepared in an in situ manner, an organic matrix in the composite hydrogel is an overoxidation micelle (pMIC) polyacrylamide gel prepared by using a pre-irradiation method, an overoxidation linear polymer chain polyacrylamide gel or a polyvinyl alcohol gel, and a mass ratio of the HAP to the polymer in the composite hydrogen is 1:5-1:3. According to the present invention, a freezing-defrosting circulation method is adopted to treat a gel, and an electrophoresis method is adopted to generate HAP nanoparticles inside the gel in an in situ manner, such that the HAP nanoparticles are uniformly dispersed in the gel, and HAP having a hollow sphere structure is obtained so as to enhance mechanical property and improve biological activity, such that potential application values in articular cartilage repair and tissue engineering materials are provided.

The invention discloses a method for acquiring a neutron protective fabric by doping rare earth element. The method comprises the following steps: (1) a, conducting pre-irradiation treatment on a textile by electron beam or plasma, and grafting the rare earth nanometer powder to the treated textile; or b, doping a rare-earth nanometer powder or rare earth salt into the textile, and conducting co-irradiation on the textile by electron beam or plasma; and (2) finally baking to obtain the neutron protective fabric. The invention acquires the flexible neutron protective fabric by doping rare earth element; the neutron protective fabric can effectively prevent slow neutron, thermal neutron and intermediate neutron, and especially shows obvious effect on fast neutron protection. According to the invention, rare earth element is grafted onto the textile to realize the flexible neutron prevention; and the method has great significance to solve a problem of neutron radiation protection and improve the added value of textile and rare earth.

The invention relates to a polyethylene-polystyrene foam, which is formed in a way that polystyrene is grafted on a molecular chain of polyethylene to connect the polyethylene with the polystyrene by a covalent chemical bond, wherein the grafting ratio mass percent of the grafted polystyrene is 25-60%, and the volume density of the polyethylene-polystyrene foam is 27-208kg/m<3>. The preparation method comprises the following steps: carrying out pre-irradiation treatment on the polyethylene; and adding the polyethylene after the pre-irradiation treatment, dispersant, functional monomer, emulsifying agent, nucleating agent and homopolymerization depressor to a reaction vessel to be subject to suspension graft polymerization reaction, adding foaming agent, cooling the reaction product, filtering, washing with water, drying, and heating to obtain the polyethylene-polystyrene foam. The polyethylene-polystyrene foam has the advantages of excellent mechanical property, favorable rebound elasticity, good stress cracking resistance, high impact absorbing capacity and the like, combines the flexibility of polyethylene foam and the rigidity of polystyrene foam, and is used in the fields of vehicles, buildings, packaging, heat preservation, heat insulation and the like.

The invention relates to strongly alkaline anion exchange fibers as well as a preparation method and applications thereof. The preparation method comprises the following steps of: using polypropylene fiber as the matrix to perform the pre-irradiation graft of acrylamide, performing Hofmann degradation to obtain PP-g-VAm (polypropylene-grafted-polyvinylamine) fiber, then using the weakly alkaline ion exchange fiber (PP-g-VAm) as the matrix and ammonium ceric nitrate as the initiator to respectively graft 2,3-epoxypropyl trimethyl ammonium chloride and (2-(acryloyloxy)ethyl)trimethylammonium chloride (DAC) and prepare the strongly alkaline anion exchange fiber PP-g-VAm-ETA (polypropylene-grafted-polyvinylamine-ethylene/vinyl acetate) and the strongly alkaline anion exchange fiber PP-g-VAm-DAC (polypropylene-grafted-polyvinylamine-DAC), wherein the strongly alkaline group contents are respectively 2.4105-4.2018mmol/g and 2.5567-4.2217mmol/g. The two fibers are applied in the adsorption and desorption of nitrate ions. A static adsorption experiment shows that the maximum adsorption capacities of the two fibers to nitrate ions are respectively 11.24mg/g and 9.79mg/g and the desorption rates are more than 97%; and the two fibers can perform selective adsorption to nitrate ions and the impact of the other negative ions such as chloride ions, on the nitrate ion adsorption performance of the fibers is little.

A status estimation device for ultraviolet curable resin includes a probe configured to irradiate an ultraviolet curable resin with excitation light, a wavelength demultiplexer configured to receive fluorescence produced from the ultraviolet curable resin and detect spectral distribution of the fluorescence, and a computer configured to estimate status of the ultraviolet curable resin by comparing a shape of pre-irradiation spectral distribution detected when the ultraviolet curable resin is irradiated by excitation light before being irradiated by ultraviolet radiation with a shape of post-irradiation spectral distribution detected when the ultraviolet curable resin is irradiated by excitation light after being irradiated by ultraviolet radiation.

The invention discloses a method for polyethylene to graft glycidyl methacrylate. The method includes the following steps: under the condition of room temperature, polyethylene is preirradiated into the air, in water containing dispersing agent and under the condition of no oxygen and heating, and grafting reaction is carried out on the polyethylene initiated by pre-irradiation and glycidyl methacrylate, thus completing grafting. The invention takes water as reaction medium, no organic solvent is used in grafting process, grafting efficiency is high, reaction post processing is simple, monomer recovery is convenient, the method is economic and environmentally friendly, and the method can be carried out in low dosage irradiation at normal temperature in the air.

The invention relates to a polyolefin thermoplastic elastomer blood storage material which comprises component A, component B and component C; wherein the middle part of component A is a random copolymer segmer of ethene and 1-butylene or a random copolymer segmer of ethene and propylene, two ends are provided with a block polymer with styrene block for end capping, and the component A takes 60-76 percent of the gross weight of the material; component B is ethene-vinyl acetate (EVA) resin and takes 10-28 percent of the gross weight of the material; component C is polyethylene (PE) resin and takes 10-20 percent of the gross weight of the material. A preparation method is combining the pre-irradiation treatment of one component with a melt-blending and micro-crosslinking method to prepare the polyolefin thermoplastic elastomer blood storage material. The invention can be used for manufacturing a blood bag, a conduit, a component and the like for storing human blood and blood component. During the processing, promoters such as plasticizer, antioxidant and the like are not added, micromolecular organic substance separation and pollution of liquid medicine and blood do not occur, and the polyolefin thermoplastic elastomer blood storage material is harmless to human body and the environment.

The invention discloses a Pb<2+>-doped ultraviolet long-afterglow luminescent material and a preparation method thereof. The luminescent material uses Sr2MgGe2O7 as a matrix and doping Pb<2+> ions as activation ions, wherein the Pb<2+> ions account for 0.05 to 2 mol% of the luminescent material. The preparation method comprises the following steps: mixing raw materials with a fluxing agent; carrying out low-temperature pre-burning at first; and then carrying out high-temperature sintering so as to obtain the ultraviolet long-afterglow luminescent material. The luminescent material prepared in the invention presents strong single-band ultraviolet long-afterglow luminescence performance. The peak of ultraviolet long-afterglow luminescence located at the position of 370 nm and afterglow time is as long as 12 h. Meanwhile, the material presents excellent photoexcitation luminescence performance. A sample having undergone high-energy ultraviolet pre-irradiation has obviously improved ultraviolet afterglow intensity after excitation by low-energy light (white light or near infrared light). The ultraviolet long-afterglow luminescent material has potential application value in fields like photochemical catalysis, disinfection and sterilization, counterfeiting prevention and medical photodynamic therapy.