37results about How to "Moderate water absorption" patented technology

The invention discloses film-coated base paper and a production process thereof. The process comprises the steps: mixing chemi-mechanical pulp, needle leave pulp, broad leave pulp and waste stuff to obtain film-coated base paper core layer pulp; mixing the needle leave pulp and broad leave pulp to obtain a surface layer pulp; mixing the needle leave pulp and the broad leave pulp to obtain surface layer pulp bottom layer pulp; facilitating the three parts of pulp to enter a pulp flow box by virtue of a quantization pump and then enter a net part to be composited, and then sequentially squeezing, drying, gluing, drying, press polishing to obtain a finished product. On the premise of guaranteeing the product quality, by improving the pulp proportion and the process, the waste stuff is added into the traditional process formula, so that the use amount of the chemi-mechanical pulp can be increased, the use amount of the broad leave pulp and the needle leave pulp can be reduced, and particularly the use amount of imported pulp can be reduced.

A preparation method of a silk fibroin / hydroxyapatite / collagen composite porous stent comprises the following steps: filling a mixture of NaCl and hydroxyapatite into an injector, wherein the mixture has a particle size of 100-425 microns and a mass ratio of NaCl and hydroxyapatite of 1:0.02-0.08; adding a mixed solution of a collagen aqueous solution with a mass fraction of 6% and a silk fibroinaqueous solution with a mass fraction of 6%, wherein each gram of NaCl is added with 1 ml of the mixed solution; pushing the piston handle of the injector to allow the mixed solution to pass the mixture of NaCl and hydroxyapatite; allowing the mixture to stand at room temperature for 24 hours; taking out the bonded block from the injector, soaking and washing. The invention can prepare stents with various pore sizes by adjusting the particle sizes of NaCl, and the prepared stent has a uniform pore size, high porosity, good pore connectivity, moderate water absorption and expansion rate. Test results show that the stent has good in-vitro and in-vivo biocompatibility.

The invention relates to protective covering paper and a preparation method thereof, belonging to the technical field of building materials. The protective covering paper is prepared from the following raw materials: 80-100 parts of modified wood fibers, 10-15 parts of polypropylene-based isothiocyanate, 5-8 parts of carboxymethyl cellulose, 3-5 parts of shell-lac and 60-70 parts of water. The modified wood fibers are prepared by the following steps: beating needle leaf wood fibers, mixing the pulp with a calcium chloride solution, adding a sodium carbonate solution dropwise, stirring for carrying out reaction, then filtering and washing to obtain the modified wood fibers. The polypropylene-based isothiocyanate is prepared by the following steps: mixing mustard seeds with water, heating the mixture, taking out and drying, crushing, squeezing, and filtering to obtain filtrate; mixing the filtrate with anhydrous ethanol, then adding a catalyst, stirring for carrying out reaction, and distilling. The protective covering paper prepared by the method is better in bonding property with a gypsum board, does not easily have the phenomena of layering and blistering, and is higher in strength.

The invention relates to degradation-controllable super absorbent resin and a preparation method thereof. The whole resin is of a three-dimensional network structure, and is composed of a three-dimensional network matrix and slow-release degradation catalyst particles dispersed in the three-dimensional network matrix; a molecular chain of the three-dimensional network matrix is composed of an acrylic acid chain segment, a sodium acrylate chain segment, an acrylic acid-2-ethylhexyl ester chain segment, an acrylamide chain segment and a diacrylamide-terminated polyether polyurethane (cross-linking agent) chain segment; the slow-release degradation catalyst particles are a PBS-coated solid acid catalyst. The preparation method comprises the following steps that: with acrylic acid, sodium acrylate, acrylic acid-2-ethylhexyl ester, and acrylamide adopted as reaction monomers, diacrylamide-terminated polyether polyurethane as a cross-linking agent and slow-release degradation catalyst particles as an additive, polymerization reaction is carried out under the action of an initiator to prepare the degradation-controllable super absorbent resin. The method disclosed by the invention is simple; and the prepared resin is not degraded within 2-3 years and is completely degraded within 6 months after being used.

The invention relates to a double-component nano high-polymer sand stabilization material which is composed of a component A and a component B, wherein the component A is composed of an inorganic-nanoparticle-modified polyvinyl alcohol-epoxy resin blend, and the component B is composed of a polyurethane prepolymer. The component A is prepared by the following steps: dispersing nano silicon dioxide in N,N-dimethylformamide, heating to 80-100 DEG C, adding polyvinyl alcohol while stirring until the polyvinyl alcohol is completely dissolved, sequentially adding an epoxy resin and a crosslinking agent DMP30, continuing stirring for 1-3 hours, and cooling to room temperature. The component B is prepared by the following steps: adding castor oil into N,N-dimethylformamide, heating to 40-60 DEG C, adding tolyl-2,4-diisocyanate while stirring, continuing stirring to react for 0.5-1.5 hours, and cooling to room temperature. The invention also relates to a sand stabilization method of the material. The sand stabilization material has the characteristics of high sand stabilization strength, high durability, moderate water absorptivity, high water stability and favorable ultraviolet radiation aging resistance under lower consumption conditions.

The invention discloses a biodegradable agricultural super absorbent resin, which is prepared with the main raw materials by weight ratio as follows: 100 portions of crop biomass, 50-150 portions of acrylic acid, 200-1,000 portions of 1% sulfuric acid aqueous solution, 7-70 portions of sodium hydroxide, 0.25-10.0 portions of N,N`-methylene-bis-acrylamide as cross-linker, as well as at least an initiator selected among 0.5-15.0 portions of persulphate, 0.5-10.0 portions of ferric salt and 0.5-8.0 portions of sodium salt. The resin has good biodegradable performance, moderate water absorption, and greatly reduced costs. The invention also discloses a preparation method of the biodegradable agricultural super absorbent resin.