▎ 摘　　要

NOVELTY - A composite film comprises hydroxyethyl cellulose, nanoclay and graphene. The mass ratio of the hydroxyethyl cellulose to nanoclay is 5-50:1, and the mass ratio of the hydroxyethyl cellulose to graphene is 5-10:1. The nanoclay is a rod-like structure having a thickness of 1-1.5 nm, and radial length of 90-120 nm. The graphene has a thickness of 0.1-0.5 nm. USE - The composite film is used in material packaging, fire protection, electrical appliances and sensors (all claimed). ADVANTAGE - The composite film is easily degradable and is prepared using simple and environmentally-friendly method which is easy to operate, suitable for large-scale production, effectively solves white pollution caused by plastic products, and reduces pressure on the environment. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the composite film, which involves dissolving hydroxyethyl cellulose in water, adding nanoclay, stirring at high speed to obtain uniformly mixed hydroxyethyl cellulose-clay dispersion, adding graphene, stirring to obtain mixed solution, and drying the mixed solution.