▎ 摘　　要

NOVELTY - Preparing high thermal conductivity polymer composite film with forest distributed structure comprises e.g. (i) synthesizing by hydrothermal method, controlling the growth of crystal morphology in the high pressure reactor to obtain one-dimensional nanowire type material, uniformly dispersing the nanowire material in N,N-dimethylacetamide (DMAc), preparing into DMAc, ethanol or water nanowire dispersion in ethanol or water solvent respectively, (ii) adding polyimide resin, ODA (4,4'-diaminodiphenyl ether)-BTDA (3,3',4,4'-benzophenonetetracarboxylic dianhydride) system as an example, adopting in-situ polymerization, adding the DMAc dispersion of nanowires obtained in the step (i), stirring for 3-24 hours until the reaction is complete to obtainnanowire/polyamic acid glue or using powder/granular polymer raw materials, heating the polymer powder/colloid and melting into a viscous fluid state, adding the one-dimensional nanowire material dispersion and fully mixing. USE - The method is useful for preparing high thermal conductivity polymer composite film with forest distributed structure. ADVANTAGE - The method: increases the contact area between the composite film and the heat source; produces product having excellent mechanical properties and high thermal conductivity. DETAILED DESCRIPTION - Preparing high thermal conductivity polymer composite film with forest distributed structure comprises (i) synthesizing by hydrothermal method, controlling the growth of crystal morphology in the high pressure reactor to obtain one-dimensional nanowire type material, uniformly dispersing the nanowire material in N,N-dimethylacetamide (DMAc), preparing into DMAc, ethanol or water nanowire dispersion in ethanol or water solvent respectively, (ii) adding polyimide resin, ODA (4,4'-diaminodiphenyl ether)-BTDA (3,3',4,4'-benzophenonetetracarboxylic dianhydride) system as an example, adopting in-situ polymerization, adding the DMAc dispersion of nanowires obtained in the step (i), stirring for 3-24 hours until the reaction is complete to obtainnanowire/polyamic acid glue or using powder/granular polymer raw materials, heating the polymer powder/colloid and melting into a viscous fluid state, adding the one-dimensional nanowire material dispersion obtained in the step (i) and fully mixing, stirring in the mixer to make the dispersed phase uniformly dispersed in the continuous phase to obtain nanowire/polymer composite glue, (iii) using the thermal chemical vapor deposition method (TCVD method), relying on the assistance of plasma, realizing the growth of graphene at low temperature based on copper foil, high-purity methane (CH4) is the precursor carbon source, using high-purity hydrogen as etching and protective gas, and argon (Ar) as carrier gas to obtain graphene under vacuum at 1000 degrees C, (iv) preparing graphene/nanowire/polymer composite thermal conductive film by transferring graphene, growing graphene on a copper catalytic substrate, transferring from the surface of the copper foil to the target resin matrix, where the nanowires exposed on the surface of the polymer matrix and the graphene sheets form a tree-leaf structure, forming thermal conduction path on both sides of the polymer matrix and firmly bonding to the matrix without falling off, where the specific steps are spin-coating the nanowire/polymer composite glue solution obtained in the step (ii) on the graphene surface, and attaching another graphene-copper foil substrate on the other side of the glue solution, curing the resin completely through gradient heating to obtain 5-layer structure of copper foil-graphene-nanowire/polymer composite film-graphene-copper foil, using ferric chloride (FeCl3) solution for etching the copper foil catalytic substrate of graphene on both sides to obtain composite thermally conductive film with a graphene-nanowire/polymer composite film-graphene sandwich structure.