Biodegradable materials Research Institute original report, PBAT is a fully biodegradable plastic. In this paper, the preparation method and two kinds of production technology are described. At present, PBAT is used in supermarket shopping bags, takeout meal boxes, agricultural plastic mulching and other fields of agriculture, industry and medicine. With the introduction of plastic limit and the expansion of green consumption market, PBAT as an environmental protection material has a good development prospect.

The full name of PBAT is Poly (adipate)/butyleneadipate-co-terephthalate, which is the abbreviation of Poly (Butyleneadipate-co-terephthalate)

From its chemical structure formula, PBAT is a copolymer of butylene adipate (BT) and butylene terephthalate (BT). Both PBA(polybutylene adipate) and PBT(polybutylene terephthalate) characteristics, not only good mechanical properties, but also has high ductility and elongation at break, but also has excellent biodegradability, is a full biodegradable plastic.

Biodegradable plastic is in the soil, sand and other natural conditions, with microorganisms (such as bacteria/mold/algae, etc.) degradation of carbon dioxide, water and other small molecules or low molecular compounds of plastic. Degradable plastics are mainly divided into photodegradable plastics, biodegradable plastics, photobiodegradable plastics. Photodegradable plastics need sufficient light to degrade, which brings great limitations to production, so the promotion of photodegradable plastics is not good.

There are dozens of biodegradable plastic varieties, which can be mass-produced and industrialized. Microbial fermentation polyhydroxy fatty acid ester synthesis, chemical synthesis of polylactic acid (PLA), poly (caprolactone dicarboxylic acid, glycol aliphatic polyester (PBS), aliphatic and aromatic copolyester, CO2 / epoxy compound copolymer (APC), polyvinyl alcohol (PVA), such as starch based plastics and biodegradable natural polymer blend of plastic, plastic alloy, etc.

Using adipic acid (AA), terephthalic acid (PTA) and butanediol (BDO) as monomers, polyadipic acid/butanediol terephthalate was synthesized according to a certain proportion. The key point of the process was to strictly control the esterification mode, esterification time, polycondensation temperature and stabilizer.

These key factors can directly affect the synthesis process and ultimately affect the performance of the product. In order to ensure the preparation of good PBAT resin, the optimum technological conditions were as follows: coesterification reaction mode, esterification time of 185 min, polycondensation temperature of 248 ~ 250 ℃, stabilizer dosage of 70 μg/g.

PBAT, as an environmentally friendly material with good performance, can reduce the consumption of petroleum resources and alleviate "white pollution", which is of great significance to the sustainable development of China. At present, the global PBAT market demand is strong, because the price of PBAT is high, and China has good raw material production conditions. PBAT products are mainly used for export, with high industry concentration, large potential market and good industrialization prospect.