In order to improve the gas barrier properties of PET films, the intercalated sericite was used as a barrier material in the functional silicone resin coatings. Firstly, the functional silicone resin with excellent thermal properties and high crosslinking degree was prepared. Secondly, lamellar sericite was intercalated and characterized by SEM and XRD. It was found that the lamellar spacing changed to 1.053 nm, and the compatibility in silicone resin was improved. Finally, the water vapor permeability (WVTR) and the oxygen permeability (OTR) of the 2 modified PET film were tested. The results showed that WVTR and OTR of the modified PET film reached 12.40 g/(m •24 h) and 29.91 3 2 cm /(m •24 h•0.1 MPa) respectively, which indicated that the silicone resin modified by intercalated sericite successfully prevents the direct penetration of gas molecules, thus forming a "loop" when gas enters, prolonging its permeation path and effectively realizing high gas barrier performance. Research Paper ES Materials & Manufacturing Sericite was obtained from Chuzhou Yonghe Sericite Co., Ltd(Anhui China), γ-glycidyl-ether-oxypropyl-trimethoxysilane (KH560), γmethacryloxypropyl trimethoxysilane (KH570), trimethylolpropanetriacrylate (TMPTA) were purchased from Qufu Chengguang Chemical Co., Ltd(Shandong China). N-dimethylaminoethyl-methacrylate (DMAEMA) was procured from Shanghai Tengquan Biotechnology Co., Ltd. 2-ethylBase-4-methylimidazoxane was supplied by Sarn Flower Technology Co., Ltd. Benzophenone was purchased from Beijing Brillingway Technology Co., Ltd. Cetyltrimethylammonium bromide (CTAB) and NaCl were procured from Shanghai Chemical Reagent Co., Ltd. Dense HNO and ethanol were obtained from Xilong 3 Chemical Co., Ltd. Polyether amine D230, hexanediol diacrylate (HDDA), sodium hydroxide were all got from Aladdin reagent Co., Ltd. All the reagents were used as received. Publisher's Note Engineered Science Publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.