▎ 摘　　要

NOVELTY - Complete biodegradable material comprises 5-15 pts. wt. polybutylene carbonate, 60-80 pts. wt. polylactic acid, 15-25 pts. wt. polybutylene adipate terephthalate copolymer, 1-5 pts. wt. lubricant, 4-8 pts. wt. chain extender and 5-10 pts. wt. compatibilizer. USE - As complete biodegradable material. ADVANTAGE - The apparent viscosity of the melt of polybutylene carbonate/polylactic acid/polybutylene adipate terephthalate blended material is in the shear rate of 0-1000 rad/second, which decreases greatly with the increase of shear rate, and tends to be stable when the shear rate is greater than 1000 rad/second. The method avoids temperature fluctuations during processing of the polybutylene carbonate/polylactic acid/polybutylene adipate terephthalate blends with high polybutylene adipate terephthalate content, where the temperature change has a greater impact on the viscosity. The tensile strength of the blend material with a mass ratio of polybutylene carbonate/polylactic acid/polybutylene adipate terephthalate of 15:70:25 can reach 23.59, which is 1.54 times of the polybutylene carbonate/polylactic acid/polybutylene adipate terephthalate mass ratio of 5:60:15, which has the best comprehensive mechanical properties. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the biodegradable material production process, involves (a) placing polylactic acid, polybutylene adipate terephthalate copolymer and polybutylene carbonate masterbatch in drying oven, and drying at 80degrees Celsius for 12 hours, (b) adding obtained material after drying to high-mixer for pre-mixing for 5 minutes, heating obtained mixture for 5 minutes at a heating temperature of 100degrees Celsius and rotating speed of 600 rpm, heating lubricant, chain extender and compatibilizer to premix product, heating the mixture with high-speed mixer for uniform stirring at 300 rpm for 1-5 minutes, where the heating temperature of high-mixer is 100degrees Celsius, and the rotation speed is 300 rpm, (c) adding color masterbatch to film blowing machine, blowing the film to obtain film, setting temperature of plasticizing section of film blowing machine to 120-145degrees Celsius, temperature of homogenizing section to 130-145degrees Celsius, and temperature of extrusion section to 120-145degrees Celsius, and (d) heat sealing, sealing and bag making of film making machine to required finished product to obtain finished product bag.