Biodegradable plastic refers to degradation caused by the action of microorganisms in nature under natural conditions such as soil and/or sand, and/or specific conditions such as composting conditions or anaerobic digestion conditions or in aqueous culture fluids. Eventually, it will be completely degraded into carbon dioxide (CO2) or/and methane (CH4), water (H2O) and mineralized inorganic salts of the elements contained therein, as well as new biomass (such as microbial dead bodies, etc.).
It should be noted that every biodegradable material requires certain environmental conditions for its degradation. If it does not have the degradation conditions, especially the living conditions of microorganisms, its degradation will be very slow; at the same time, not every biodegradable material It can be quickly degraded under any environmental conditions. Therefore, when dealing with biodegradable materials, we should start from its environmental conditions and analyze the structure of the material itself to determine whether it is a biodegradable material.
What types of biodegradable plastics are there?
According to the source of raw materials, it can be divided into two types: bio-based biodegradable plastics and petrochemical-based biodegradable plastics.
There are four main types of bio-based biodegradable plastics:
The first category is plastics directly processed from natural materials. At present, there are mainly thermoplasticity starch, biocellulose, polysaccharides and polyamino acids, as well as their blended and chemically modified products;
The second category is polymers obtained through the joint participation of microbial fermentation and chemical synthesis, such as polylactic acid (PLA), etc.;
The third category is polymers directly synthesized by microorganisms, such as polyhydroxyalkanoates (PHA), etc.;
The fourth category is biodegradable plastics obtained by blending these materials, or by blending these materials with other chemically synthesized biodegradable plastics.
Petrochemical-based biodegradable plastics refer to plastics obtained by polymerizing petrochemical monomers by chemical synthesis, such as polybutylene terephthalate adipate (PBAT), polybutylene succinate (PBS) ), carbon dioxide copolymer (PPC), polyglycolic acid (PGA), etc.
