Starch modified PBAT
Starch is mainly obtained from corn, potato and other crops through processing. It is a common biodegradable material. It has the advantages of wide source, low price, renewability and rapid degradation. It is polybutylene terephthalate. (PBAT) modified ideal filler material. However, starch itself has poor plasticity, and there are intermolecular and intramolecular hydrogen bonds, so it has certain crystalline properties.
Therefore, when filling with starch, it is necessary to pre-process the starch, and add cross-linking agents, plasticizers, etc. to make starch powder into powder. The easy-to-add granules facilitate the modification of PBAT to obtain PBAT/starch blends with good comprehensive properties. Starch is plasticized by adding plasticizers such as glycerol and water. After plasticization, the hydrogen bonds between starch molecules are weakened and destroyed, the diffusion capacity of molecular chains is improved, and the glass transition temperature of the material is lowered. Therefore, the melting of crystallites is achieved before decomposition, and the double helix conformation is transformed into a random coil conformation, so that the starch has the possibility of thermoplastic processing. The processing temperature of thermoplastic starch is 120~220 ° C, and then plasticized The starch and PBAT are blended on a twin-screw extruder, and a new starch-filled modified PBAT biodegradable plastic may be obtained. This biodegradable plastic can be made into a film and is an environmentally friendly material with broad application prospects.
