▎ 摘　　要

NOVELTY - Stiffening masterbatch comprises stiffening agent composed cage-type polysilsesquioxane-g-graphene doped silicon dioxide, where the cage-type polysilsesquioxane is amino or hydroxyl full-functional group cage-type polysilsesquioxane, graphene doped silicon dioxide is a core-shell structure of graphene-coated silica, the amino or hydroxyl groups of cage-type polysilsesquioxane are exposed to graphene doped silicon dioxide, the carboxyl groups exposed on the graphene surface undergo amide and/or esterification reactions, grafted onto the graphene doped silicon dioxide structure, a cage-type polysilsesquioxane-g-graphene doped silicon dioxide with a three-dimensional network structure is obtained. USE - Used as stiffening masterbatch. ADVANTAGE - The stiffening agent has chemical bond force, forms a molten community, generates synergistic effect, stable structure, good compatibility, avoids the processing and using process in phase separation and precipitation. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing reinforcing master batch comprising: (1) graphene doped silicon dioxide core-shell structure; the carboxylated graphene and amino silicon dioxide, graphene coated on the surface of the silicon dioxide to form graphene doped silicon dioxide coreshell structure, (2) preparing stiffening agent by grafting the amino or hydroxyl functional cage polysilsesquioxane to the surface of graphene doped silicon dioxide prepared in step (1), forming cage-type polysilsesquioxane-g-graphene doped nano silicon dioxide with three-dimensional net structure, (3) preparation of master batch: the stiffening agent prepared in step (2), homopolymerized polypropylene and compatilizer into the extruder, heating and melting and mixing uniformly, reinforcing agent and graphene doped silicon dioxide dispersed in the polypropylene, forming polypropylene-compatilizer-cage type polysilsesquioxane-g-graphene doped SiO2 composite system, extruding to obtain the reinforcing master batch by the die. INDEPENDENT CLAIMS are also included for: polyolefin film comprising the reinforcing master batch; and BOPP film, comprising the reinforcing master batch.