Preparation method of polylactic acid-based nanocomposite film with high strength and barrier property

Abstract

The invention relates to a preparation method of a polylactic acid-based nanocomposite film with high strength and barrier property. The raw materials of the composite film comprise polylactic acid, carbon nanotubes, a KH-550 silane coupling agent, nanofibrillated cellulose and ethanol. The polylactic acid-based nano composite film with high strength and barrier property is obtained through the preparation of a silane modifier, silanization modification of the nanofibrillated cellulose and solution casting and shaping of the polylactic acid-based nanocomposite film. The polylactic acid-based nanocomposite film has wide sources of raw materials and a simple preparation process, the production cost can be effectively reduced, and economic benefits can be effectively increased. More importantly, the agglomeration effect is improved after the modification of the carbon nanotubes and coating of the nanofibrillated cellulose, the interfacial compatibility between the polylactic acid, the carbon nanotubes and the nanofibrillated cellulose is better improved, and correspondingly the enhancement effect of the carbon nanotubes and the nanofibrillated cellulose on the polylactic acid is improved. Not only is the mechanical performance of the polylactic acid-based nanocomposite film improved significantly, but also the barrier property is greatly enhanced.

Description

technical field

[0001] The invention relates to the field of preparation of composite films, in particular to a preparation method of high-strength and high-barrier polylactic acid-based nano-composite films. Background technique

[0002] As one of the most valuable biodegradable polymers for development and application, polylactic acid is mainly derived from natural renewable plant resources, such as the fermentation of corn starch and beet sugar. Polylactic acid can be hydrolyzed or completely degraded by microorganisms in the natural environment, and finally becomes carbon dioxide and water. Polylactic acid is linearly polymerized, with almost no side chain active groups, elongation at break ≤ 10%, and its glass transition temperature (Tg) is only 55°C. Low strength, poor impact resistance, etc.; and nanoparticles can well make up for the shortcomings of polylactic acid with its unique size effect, high aspect ratio, excellent mechanical properties and heat resistance. ...