39results about How to "Shear thinning" patented technology

The invention discloses a method for preparing a vinyl chloride-vinyl acetate copolymer paste resin by utilizing emulsion polymerization. The method comprises the following steps: under an anaerobic airtight condition, performing polymerization reaction on a compound emulsifier, a trigger, desalted water, a pH regulator, a first generation seed, a second generation seed, a vinyl chloride monomer and a vinyl acetate monomer, thereby preparing the vinyl chloride-vinyl acetate copolymer emulsion, wherein the polrvinyl chloride emulsion is taken as the first generation seed with an emulsion grain size of 100-200nm and a solid content of 25-50%, and the polrvinyl chloride emulsion is taken as the second generation seed with the emulsion grain size of 700-1000nm and the solid content of 25-50%. According to the method, the emulsion of the first generation seed and the second generation seed are added in a copolymerizing system; the copolymer emulsion is prepared; and after the copolymer emulsion is subjected to spray drying, the vinyl chloride-vinyl acetate copolymer paste resin with lower B type paste viscosity is obtained. The method has the advantages of simple process, large controllable scope of the emulsion grain size, and wide application scope of post processing.

The invention relates to a method for preparing a photosensitive nanocomposite supramolecular hydrogel. In tetrahydrofuran solvent, mercaptopolyethylene glycol monomethyl ether or polyethylene glycol monomethyl lipoate is used as a stabilizer, and chloroauric acid is reduced in situ to form polyethylene glycol monomethyl ether under the action of a reducing agent. Assembling the gold nanocomposite particle of single-layer protection, then the aqueous solution of gold nanoparticles self-assembled single-layer protection of polyethylene glycol monomethyl ether with a mass percentage concentration of 3-20% and a mass percentage concentration of 5-12% α - Cyclodextrin aqueous solution mixed, α -Cyclodextrin is assembled with polyethylene glycol monomethyl ether on the surface of gold nanoparticles to obtain a photosensitive nanocomposite supramolecular hydrogel. The synthesis method of the invention is simple and easy, and the prepared gold nano composite particles have good water dispersibility and stability, and the nano gold is uniformly distributed in the composite supramolecular hydrogel. The nanocomposite supramolecular hydrogel prepared by the invention not only has the performance of shear thinning, but also has photosensitivity, and is expected to be used in the field of biomedical engineering materials as a new injection implant functional material.

The invention provides a method for preparing a high-porosity bone tissue scaffold composite by 3D printing, and belongs to the field of additive manufacturing (3D printing). The method provided by the invention is based on a 3D gel technology and a pore former method. The method comprises the steps that firstly, a low-cost pore former and ceramic powder are uniformly mixed to prepare low-viscosity and high-solid-content slurry suitable for printing in combination with a gel system, and a blank body with macroscopically-visible pores is prepared with 3D gel printing; then the blank body is dried, degreased and sintered; and the pore former is decomposed and oxidized to be discharged into air to form microscopic pores, so that the high-porosity bone scaffold composite is obtained finally. The method provided by the invention can precisely control the size, shape and distribution of the macroscopic pores, realizes the preparation of the high-porosity bone tissue scaffold composite with low cost, and has a simple process and low cost.