Plastic as a kind of high polymer material is made by adding some additives like padding, plasticizer, stabilizer, and pigment into resin, and is plasticized and molded under designated temperature and pressure. Usually plastic product keeps unchangeable shape in room temperature, and we may divide plastic resin into several types, including polyethylene, polypropylene, polystyrene, PVC, and polyethylene terephthalate.
Since plastic is characterized by well self-formation ability, corrosion resistance, water proof property, and lightness, it is easy for us to see it being widely used in many areas such as packaging of daily essentials, and industries of automobile parts, building materials, and electronic communication.
Nowadays, biodegradable materials are increasingly replacing the traditional petroleum products with the increase trend in energy price and the urgency being felt in environment protection. It also means that we will see a wider application for degradable plastic, especially for biodegradable plastic that is sure to gradually replace traditional non-degradable plastic and gets a bigger market share. It is estimated that the bright future of biodegradable plastic is for sure.
Biodegradable plastic refers to a kind of plastic whose chemical structure is obviously changed under certain circumstance, and it can be naturally degraded. It generally falls into several types, like biodegradable plastic, photodegradable plastic, and many other plastics. Among them the photodegradable plastic will be gradually degraded by sunlight, and photosensitizer is also necessary in this process. People now seldom use photosensitizer since it is itself poisonous. With the role played by microorganism, biodegradable plastic can be fully degraded into low molecular compound plastic, which is being widely used with its well performances.
Different additives added into degradable plastics determine the various types of them, like starch-based degradable plastic, PBS and PVOH petroleum-based degradable plastic, PLA degradable plastic, and polyhydroxyalkanoates degradable plastic. As polyhydroxyalkanoates are natural polymer polyesters, they can be completely degraded without compost. Excellent performance makes it possible for them being widely used in various areas.
Anyway, we can get biodegradable materials by directly producing high polymer materials like PHAs with biological know-how, or by polymerizing certain raw materials into PLA, PBS, and polyamino acid. In addition, starch-based biodegradable plastic and APC are all included here. PLA, PHAs, and PBS are most researched in biological materials for recent years, and along with starch-based biodegradable plastic they have become the mainstream among many biodegradable material technologies all over the world. Relatively, their techniques are characterized by maturity, and the large industrialization scale is inevitable. So they lead the major consumption in market.