▎ 摘　　要

NOVELTY - Composite plastic sheet comprises 37-43 pts. wt. polyvinyl alcohol, 26-35 pts. wt. polybutylene succinate, 23-27 pts. wt. sweet potato starch, 7-15 pts. wt. whey protein, 15-25 pts. wt. zein, 12-17 pts. wt. hyperbranched poly(trimellitic acid), 8-12 pts. wt. graphene oxide, 5-10 pts. wt. polyvinyl alcohol fiber, 3-6 pts. wt. rice husk cellulose fiber, 2-8 pts. wt. basalt fiber, 1-3 pts. wt. plasticizer, 2-4 pts. wt. hyperbranched lubricant, 1.5-2.5 pts. wt. antioxidant and 1.7-5.6 pts. wt. amino silicone oil. USE - As composite plastic sheet. ADVANTAGE - The plastic sheet is environmentally-friendly, easy to process, and economical, has excellent mechanical properties, high strength, strong practicability, excellent toughness, and impact resistance, easily degrades, and achieves long shelf life. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the plastic sheet involving (i) placing the polyvinyl alcohol, polybutylene succinate, sweet potato starch, whey protein and zein in a plastic mixer, mixing at a speed of 500-600 rpm, under the condition of 25-33 degrees C for 20-30 minutes to obtain the base material of the board, (ii) adding hyperbranched poly(trimellitic acid), graphene oxide, polyvinyl alcohol fiber, rice husk cellulose fiber, basalt fiber to the plastic mixer in the step (i), mixing at 700-800 rpm for 30-40 minutes, adding plasticizer, hyperbranched lubricant, antioxidant and amino silicone oil, and continuously stirring for 30 minutes, (iii) placing the mixture obtained in step (ii) in the injection molding machine for heat preservation and melting for 10-14 minutes at 130-140 degrees C, and (iv) performing injection molding in injection molding machine to obtain a plastic plate, cooling, solidification molding, and cutting off the flash.