37results about How to "The degree of cross-linking is controllable" patented technology

The invention discloses a method for cross-linking and modifying medical-grade reconstructed collagen, which is characterized in that 1 to 5 weight parts of phosphate solution with the concentration of 0.1 mol / L to 0.5mol / L is added into 5 to 25 weight parts of uniform regular collagen solution with the concentration of 5 mg / ml to 10mg / ml at the temperature of 15 DEG C to 20 DEG C while slowly stirring. Acid solution or aqueous alkali is used for adjusting the pH value of the mixed solution to 7.0 to 8.5. The mixed solution stands for 6 hours to 12 hours at the temperature of 25 DEG C to 40 DEG C and humidity of 50 percent to 70 percent so as to form uniform colloid. The colloid is sequentially arranged in the environment of minus 20 DEG C to minus 40 DEG C and minus 60 DEG C to minus 80 DEG C to be frozen for 24 hours to 48 hours, and then dehydrated in a lyophilizer to obtain the reconstructed collagen with cross-linked and modified ions.

The present invention provides a closed-cell foamed rubber sheet whose sealability is less likely to decrease even after long-time use and which has excellent water resistance. The closed-cell foamed rubber sheet of the present invention comprises a rubber-based resin, and is provided by the steps of: providing a foamable resin composition containing the rubber-based resin and a foaming agent; irradiating the foamable resin composition with ionizing radiation to cross-link the foamable resin composition; and foaming the cross-linked foamable resin composition. In the case where the foamable resin composition further contains 0.5 parts by weight or more of a powdery additive other than the foaming agent per 100 parts by weight of the rubber-based resin, the rubber-based resin preferably contains a rubber-based resin ingredient which is in a liquid state at normal temperature.

The invention discloses an organosilicon insulating impregnating varnish and a preparation method thereof. The organosilicon insulating impregnating varnish comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 100 parts of polymethylphenylvinylsiloxane and 0.9-1.5 parts of platinum catalyst and the component B comprises 30-75 parts of polyhedral oligomeric silsesquioxane with ethylene group and 40-60 parts of hyperbranched polysiloxane with Si-H bond. The polymethylphenylvinylsiloxane synthesized in the preparation method of the invention adopts ethanol as solvent and is no non-toxic and non-harmful; when the prepared impregnating varnish is solidified, no by-product with low molecular weight is discharged, thus not affecting the electric performance of the insulating material; in addition the impregnating varnish has good post impregnation effect, high temperature resistance and environmental friend.

The invention discloses a nano fiber artificial blood vessel for catalyzing an endogenous NO precursor to release NO and a preparation method. The artificial blood vessel consists of a three-dimensional reticular non-woven film pipe structure formed by an inner layer of nano fibers and an outer layer of nano fibers. The artificial blood vessel is prepared by the method comprising the following steps of: dissolving gelatin, ascorbic acid and sodium nitrite in water to prepare a solution; uniformly mixing the prepared solution with an aqueous solution of a crosslinking agent to ensure that the solution is pre-crosslinked; adding a sodium heparin aqueous solution to prepare a spinning dope; collecting fibers formed by spinning on a collecting roller to form nano fiber non-woven film pipes; dissolving polyurethane and nantokite chelate in a mixed solvent of tetrahydrofuran and N,N-dimethyl fomamide to prepare a polyurethane spinning dope; spinning and continuing collecting fibers on the collecting roller with the nano fiber non-woven film pipes so as to form polyurethane non-woven film pipes; and soaking and treating the polyurethane non-woven film pipes in the aqueous solution of thecrosslinking agent. The blood vessel can catalyze to release NO for a long time and is beneficial to inhibiting the aggregation of platelets in the artificial blood vessel. The method is simple, and the degree of crosslinking is easy to control.

The invention discloses an artificial blood vessel for catalyzing an endogenous NO precursor to release NO and a preparation method. The artificial blood vessel consists of a three-dimensional reticular non-woven film pipe structure formed by an inner layer of nano fibers and an outer layer of nano fibers. The artificial blood vessel is prepared by the method comprising the following steps of: dissolving gelatin, ascorbic acid and sodium nitrite in water to obtain a spinning dope so as to prepare nano fiber non-woven film pipes; dissolving polyurethane and nantokite chelate in a mixed solventof tetrahydrofuran and N,N-dimethyl fomamide to prepare a polyurethane spinning dope; continuing collecting fibers on a collecting roller with nano fiber non-woven film pipes so as to form polyurethane non-woven film pipes; soaking and treating the polyurethane non-woven film pipes in an aqueous solution of a crosslinking agent; and cleaning and drying to prepare the artificial blood vessel for catalyzing endogenous NO precursor to release NO. The artificial blood vessel can catalyze to release NO for a long time. The method is simple, and the degree of crosslinking is easy to control.

The invention discloses a preparing method of a corrosion type silicon dioxide xerogel drug sustained-release material. The preparing method comprises the following steps: mixing and stirring 50-99 percent by weight of organo-siloxanes of which silicon atoms are all connected with alkoxy, 1-50 percent by weight of organo-siloxanes of which alkoxy is partly replaced with alkyl branches difficult to hydrolyze, a certain amount of solvent, and acid catalysts for 10-120 minutes at the temperature of 20-60 DEG C, performing the cohydrolysis and the copolycondensation, adding drug of which the weight is 0.1-50% of the total weight of the two kinds of organo-siloxanes after the sufficient reaction, adding the base catalysts to enable hydrolysates be to quickly crosslinked after the complete dissolution, stirring for 1-30 minutes, and drying to obtain the drug sustained-release material after the product is solidified. The preparing method can calculate and control the drug load accurately, and the shape and the size of the drug sustained-release material can be adjusted flexibly according to the drug releasing requirement. The preparing method is simple in process, good in biocompatibility, and non-toxic to the human body, and has a wide application prospect in controllable release and clinical trials of drug suitable for sustained-release application.

The invention discloses a polyethylene greenhouse film resin composition with high intensity and ultra-broad width and its preparation method, by referring linear low density polyethylene in weight percent, the resin composition comprises: 1) 100% of LLDPE; 2) 0.12%-0.45% of compound crosslinking auxiliary agent (1,1-hydroxyphenyl-hydrogen peroxide and 2,5-dimethyl-2,5-di-tert-butyl peroxide hexane); 3) 0.015%-0.032% of dibenzoyl peroxide; 4) 15%-37% of PP / LLDPE blended grafted polymer. According to the invention, the composition is capable of steadily blowing the ultra-broad width greenhousefilm (broad width is greater than or equal to 14m, the thickness is greater than or equal to 80 mum) on a general film blowing machine group, and the tear strength of film product is high, the product has no fish eye on the appearance, the polyethylene greenhouse film resin composition is capable of resisting 8-9 grade sand storm, and is especially suitable for laying in central and western regions in which the sandstorm occurs frequently. The present invention also discloses a preparation method of the resin composition.