Effect of chitosan concentration on physicochemical properties of starch-based biodegradable drinking straws by extrusion

As disposable plastic straws were banned in China, more biodegradable straws were invented. Under high temperature and pressure conditions, starch is pasted and the molecular hydrogen bonds between starch are broken. After adding chitosan, chitosan and starch can form new hydrogen bonds. Biodegradable starch-based straws were made from cassava starch and rice starch (weight ratio = 1:1) by extrusion technique. Chitosan (0%, 5%, 10%, 15% and 20%) was added to improve the mechanical properties of the straws and the effect of chitosan on the chemical, mechanical and water resistance properties of the starch-based straws was investigated. Color, transparency and water resistance of CR/CH (tapioca starch, rice starch and chitosan) straws containing different levels of chitosan. The color and water resistance of straws containing different levels of chitosan were superior to those of CR (tapioca and rice starch). The best mechanical properties and water resistance of starch-based straws were obtained when the chitosan addition was 5%. The addition of chitosan flattened the appearance of the starch-based straws and improved the mechanical properties and water resistance of the straws. The above structure can provide a reference for the application of starch-based materials.