5results about How to "Enhance the interface force" patented technology

This invention relates to a method for preparing integrated high thermal conductivity layered material silicone rubber gaskets for heat dissipation in electronic packaging based on peeling. The method involves mixing polydopamine-modified boron nitride or graphite powder, silicone rubber, a silane coupling agent, and a bis(2,5)-pentachlor vulcanizing agent in a three-roll mill. By reducing the roller spacing and extending the mixing time, the boron nitride or graphite powder is peeled off within the composite material under the shear force of the rollers. The resulting mixture is placed in a metal mold and subjected to vacuum hot-pressing vulcanization, followed by a secondary vulcanization, to obtain a high thermal conductivity silicone rubber gasket for heat dissipation in electronic packaging. This method has broad application prospects in the fields of electronic packaging and thermal management.

The invention relates to the field of refining and application of wood fiber biomass, and discloses a lignin-based formaldehyde-free adhesive, a lignin-based plywood and a preparation method and application of the lignin-based formaldehyde-free adhesive and the lignin-based plywood. The lignin-based formaldehyde-free adhesive disclosed by the invention comprises the following components: L-cysteine lignin, and the solid content of the lignin-based formaldehyde-free adhesive is 10-45wt%. The method comprises the following steps: mixing an aqueous solution of L-cysteine hydrochloride and lactic acid with raw materials for pretreatment; performing extraction and vacuum filtration on the obtained suspension to obtain dissolved lignin and hemicellulose filtrate, and performing extraction and purification on the filtrate to obtain L-cysteine lignin; the lignin-based formaldehyde-free adhesive is prepared by uniformly dispersing the L-cysteine lignin in water. According to the invention, the used solvent is green and nontoxic in source, the hydrated lignin-based adhesive with good fluidity is prepared with low solid content, and the prepared plywood shows excellent dry and wet bonding strength, solvent resistance and weather resistance, and meets the preparation requirements of national I-class plywood.

This invention belongs to the field of high-performance fiber composite materials technology, specifically relating to a method for preparing low-dielectric ramie fiber reinforced polycarbonate composite materials. First, ramie fibers with acrylate-type double bonds modified on their surface are prepared. Then, poly(styrene-isoprene) modified ramie fibers are prepared by copolymerizing the acrylate-type ramie fibers with styrene and isoprene. Next, polyphenylene ether and the poly(styrene-isoprene) modified ramie fibers are mixed evenly and added to a hopper. A polyphenylene ether / ramie fiber alloy is prepared using a twin-screw extruder. Finally, the polyphenylene ether / ramie fiber alloy is mixed evenly with polycarbonate and added to a hopper. A low-dielectric ramie fiber reinforced polycarbonate composite material is prepared using a twin-screw extruder. The molecular weight of the modified ramie fiber polymer is adjustable, as is the ratio of styrene to isoprene. The polystyrene segments effectively improve the compatibility between ramie fibers and polyphenylene ether, while the polyisoprene segments effectively enhance the toughness of the polyphenylene ether / ramie fiber alloy.

This invention discloses a branched vinylphenyl polysiloxane and its preparation method, comprising the following steps: mixing vinyl difunctional chain silane monomers, phenyl difunctional chain silane monomers, alkyl difunctional chain silane monomers, a solid acid catalyst, and acetic acid in a certain proportion, and performing a reflux reaction; filtering out the solid acid catalyst by cooling to obtain a first filtrate, and distilling it at atmospheric pressure to obtain a polysiloxane precursor; adding a trifunctional chain silane monomer, a capping agent, acetic acid, and a solid acid catalyst to the polysiloxane precursor, and reacting; filtering out the solid acid catalyst to obtain a second filtrate, and distilling it at atmospheric pressure to obtain a branched vinylphenyl polysiloxane with a vinyl content of 1.0~3.0% and a silanol content ≤0.1%. It can be used for surface modification of fillers in addition silicone rubber systems to improve the mechanical properties and system compatibility of materials, and solve the problems of few modified active sites and weak interfacial forces, as well as the problem that high silanol content affects the curing and adhesion of addition systems.

The present application provides an epoxy resin composition, a preparation method and application thereof, and raw materials of the epoxy resin composition include an epoxy resin, a curing agent and a modified lignin epoxy resin. The modified lignin epoxy resin is used to replace part of the traditional epoxy resin to prepare the epoxy resin composition, which can enhance the compatibility between the lignin and the epoxy resin matrix, and the interfacial force between the lignin and the epoxy resin, utilize the chemical structure characteristics of the lignin itself, enhance the tensile strength of the epoxy resin composition, on the other hand, through enhancing the interfacial adhesion between the epoxy resin composition and the substrate (especially the copper substrate), such as hydrogen bond effect, etc., the adhesion performance of the epoxy resin composition is improved.