35results about How to "Good degree of crosslinking" patented technology

The invention relates to a preparation method of carboxyl nitrile rubber through emulsion polymerization. According to the preparation method, acrylonitrile, an emulsifier, an adjusting agent, and an initiator are added into a polymerization kettle, then butadiene is added, emulsion polymerization is carried out under stirring, and in the late phase of emulsion polymerization, unsaturated carboxylic acid and / or anhydride thereof is added into the polymerization kettle. The obtained carboxyl nitrile rubber has a low content of gel and a two-layer molecular structure, the index of conjugated acid is controllable; during the processing process, a three-dimensional network structure can be easily formed, thus the mechanical and physical properties of rubber products made of the carboxyl nitrile rubber are good; after processing, the Mooney viscosity is increased, the crosslinking degree of finished products is good, and especially, the elongation at break is prominently improved.

The invention relates to a method of preparing carboxyl styrene butadiene rubber through emulsion polymerization. According to the method, styrene, an emulsifier, a conditioning agent, and an initiator are added into a polymerization kettle, then butadiene is added to carry out emulsion polymerization under stirring, and in the later period of reactions, unsaturated carboxylic acid and / or unsaturated carboxylic anhydride are added into the polymerization kettle. The prepared carboxyl styrene butadiene rubber has a low gel content, a controllable combined acid index, and a dual layer molecular structure; during the processing process, a three dimensional net-like structure can be formed easily; the mechanical and physical properties of rubber product are good, after processing, Mooney viscosity is increased, the crosslinking degree of finished product is good, and especially, the elongation at break is obviously improved.

The invention belongs to the technical field of waste polyurethane recovery and reutilization, and particularly relates to a preparation method of a graphene / waste polyurethane composite material. According to the method disclosed by the invention, the waste polyurethane rigid foam subjected to crushing and a polyol, graphene oxide and additive blending system meeting different functional requirements are degraded and recycled according to a certain proportion for reutilization, and the graphene oxide / waste polyurethane composite material with excellent performance is prepared by utilizing a degradation product. The material has good thermal stability, thermal insulation performance and the like, and the apparent density, the compression strength, the water absorption rate and the like are all higher than national standards. In the recovery process, three wastes are not discharged, the method is green and environment-friendly, the recovery utilization rate of the waste polyurethane is close to 100%, and the degradation product can be directly utilized without subsequent treatment, so that the cost of the polyurethane rigid foam product is greatly reduced.

The invention relates to a method for preparing carboxylated styrene-butadiene rubber by emulsion polymerization. Styrene, an emulsifier, a regulator, and an initiator are added to a polymerization kettle, and after adding butadiene, emulsion polymerization is carried out under stirring. In the late stage of the reaction, Add unsaturated carboxylic acid and / or its anhydride of unsaturated carboxylic acid into the polymerization tank. The carboxylated styrene-butadiene rubber prepared by the method of the present invention has low gel content, controllable binding acid index, has a double-layer molecular structure, and is easy to form a three-dimensional network shape structure during processing, and has good physical and mechanical properties of rubber products, and is easy to process. After the Mooney viscosity increases, the degree of crosslinking of the finished product is good, especially the elongation at break is significantly improved.

The invention relates to a 3D-printed degradable macromolecular scaffold and photo-crosslinked hydrogel composite scaffold. The 3D-printed degradable macromolecular scaffold and photo-crosslinked hydrogel composite scaffold comprises a 3D-printed degradable macromolecular scaffold, wherein the interior of the 3D-printed degradable macromolecular scaffold comprises photo-crosslinked hydrogel with high substitution degree and photo-crosslinked hydrogel with low substitution degree, the photo-crosslinked hydrogel with high substitution degree is crosslinked with the photo-crosslinked hydrogel with low substitution degree, and preferably, a polycaprolactone (PCL) scaffold and methacrylic anhydride gelatin (GelMA) with different substitution degrees are crosslinked and compounded. In the composite scaffold, the 3D-printed degradable macromolecular scaffold has good mechanical properties; the photo-crosslinked hydrogel with high substitution degree has high crosslinking degree, can form a fiber network and micropores, and well supports cells; and the photo-crosslinked hydrogel with low substitution degree has multiple active sites, is beneficial to cell adhesion growth, and can adsorb alarge amount of nutrient solution. Through cooperation of the 3D-printed degradable macromolecular scaffold, the photo-crosslinked hydrogel with high substitution degree and the photo-crosslinked hydrogel with low substitution degree, the composite scaffold is suitable for cell growth and vascularization from an inner layer to an outer layer, and when the composite scaffold is used for medical human body repair, scaffold integration is realized to promote regeneration of new tissues.

The invention relates to the technical field of plastic uptake materials, in particular to a high-peel-strength vacuum plastic uptake material and a preparation method thereof, wherein the high-peel-strength vacuum plastic uptake material comprises the following raw materials: polycaprolactone triol, polypropylene glycol, diisocyanate, epoxidized soybean oil / modified polyacrylate mixed solution, acatalyst, acetone, a chain extender, ethylenediamine and deionized water. The vacuum plastic uptake adhesive has higher solid content and lower thermal activation temperature, so that the curing speed is higher, and the film forming time is shorter.

The invention belongs to the technical field of food processing and safety, and in particular relates to a rose residue modified dietary fiber composite gel and a preparation method thereof. The composite gel contains rose dregs modified dietary fiber and gelatin, the content of the rose dregs modified dietary fiber is 0.1-2%, and the content of the gelatin is 5-10%. The invention creatively uses rose dregs as a source of dietary fiber, and after modification, it is used to prepare a composite gel, which has suitable hardness, elasticity and taste, and can be used as a raw material for food with certain processing strength.

The invention discloses a preparation method of a cross-linking modified polyimide organic-solvent-resistant composite membrane and the prepared composite membrane and application of the membrane, wherein the preparation method comprises an interfacial polymerization step, a chemical imidization treatment step, a replacement-solvent replacement treatment step and a cross-linking step. A solvent-resistant nanofiltration membrane prepared by the preparation method is greatly enhanced in solvent resistance; further, the separation property of the membrane is not basically changed; the membrane has quite good solvent permeability, further, is simple in preparation process, and has quite good application prospects at the aspects of the separation of an organic solvent system and the treatment of water containing organic solvents.

The invention relates to the technical field of plastic absorbing plastics, in particular to a vacuum plastic absorbing plastic with high peel strength and a preparation method thereof, comprising the following raw materials: polycaprolactone triol, polypropylene glycol, diisocyanate, and epoxy soybean oil-modified polyacrylate Mixture, catalyst, acetone, chain extender, ethylenediamine, and deionized water. The vacuum-absorbing adhesive of the present invention has higher solid content and lower thermal activation temperature, so the curing speed is faster and the film-forming time is shorter.

The invention relates to the field of medical materials, more specifically, the invention relates to a self-controlling temperature photothermal effect microsphere and a preparation method thereof. The microspheres include a core layer and a shell layer from the inside to the outside. The shell layer uses a tungsten-doped vanadium dioxide / hydrogel intermediate to cover the core structure of nanoparticles containing photothermal effects. Influenced by the phase transition temperature of vanadium oxide nanoparticles, self-controlling thermotherapy microspheres can be obtained, and the local temperature of the lesion can be precisely controlled through photothermal conversion. The invention adds W doping to the vanadium dioxide nanoparticles in the shell layer, and controls the temperature of the microspheres through the phase transition temperature, and when the doping amount of tungsten is 1.5-1.85%, the temperature can be controlled at 40-55°C. By controlling the dosage and types of hydrogel intermediates, anionic crosslinking agents and nanoparticles or tungsten-doped vanadium dioxide nanoparticles in the core layer and the shell layer, the obtained microspheres have good elasticity and drug-loading properties.

The invention relates to a method for preparing carboxylated nitrile rubber by emulsion polymerization. Acrylonitrile, emulsifier, regulator and initiator are added to a polymerization kettle, and after adding butadiene, emulsion polymerization is carried out under stirring. In the later stage of the reaction, the The unsaturated carboxylic acid and / or its anhydride are added to the polymerization tank at the end of the reaction. The carboxyl nitrile butadiene rubber prepared by the method of the present invention has low gel content, controllable binding acid index, has a double-layer molecular structure, and is easy to form a three-dimensional network shape structure in the processing process, and has good physical and mechanical properties of the rubber product, and is easy to process. After the Mooney viscosity increases, the degree of crosslinking of the finished product is good, especially the elongation at break is significantly improved.

The invention relates to a production method of photovoltaic roof tiles, which comprises the following steps: laminating in twice, and simultaneously stacking in twice, wherein in the primary laminating, products are initially evacuated, silicon cell chips are initially positioned, and package sealing compounds are initially hot melted and crosslinked; and a second layer of package sealing compounds is laid after the temperature is reduced to room temperature, and the secondary laminating is carried out after a glass covering plate is placed on the package sealing compounds. The invention hastwo-time laminating technology so as to effectively control the offset of the silicon cell chips in the laminating process, extremely improve the arrangement accuracy of cell units, and extremely reduce fracture of tile type back pieces and the silicon cell chips; optimized technology parameters ensure the optimum crosslinking extent of the package sealing compounds, and ensure the ultraviolet and aging resistant performance of the products to the full extent; and simultaneously, the optimized technology parameters are greatly reduced so as to basically avoid bubbles remained in the products.