▎ 摘　　要

NOVELTY - A surface-modified flame retardant is prepared by mixing silane coupling agent with benzene, adding azobisisobutyronitrile, continuing reaction, filtering, and evaporating excess benzene to give colorless liquid; adding graphene oxide to water, ultrasonic treating for 10-120 minutes, and obtaining graphene oxide dispersion; adding the dispersion with zinc and tin salts, reacting at 5-80 degrees C for 2-6 hours, filtering, and washing to obtain nano-zinc tin oxide/graphene filter cake; and adding the filter cake with ethanol, and performing ultrasonic dispersion. USE - Method for preparing surface-modified flame retardant (claimed). DETAILED DESCRIPTION - Preparing surface-modified flame retardant comprises mixing silane coupling agent with benzene, adding azobisisobutyronitrile, continuing reaction, filtering, and evaporating excess benzene to give colorless liquid; adding graphene oxide to water at room temperature to 80 degrees C, ultrasonic treating for 10-120 minutes, and obtaining graphene oxide dispersion; adding the dispersion with zinc and tin salts, reacting at 5-80 degrees C for 2-6 hours, filtering, and washing to obtain nano-zinc tin oxide/graphene filter cake; and adding the filter cake with ethanol, performing ultrasonic dispersion for 10-60 minutes, warming to 50-80 degrees C, adding surface modifier, adjusting pH to 8-9, reacting for 1-6 hours, washing reaction product with water, and drying.