The latest research achievement of degradable materials is that disposable tableware manufacturers naturally synthesize high polymer materials through the growth of bacteria in the fermentation place, such as polyhydroxybutyl ester (PHB), which is the real sense of biodegradable materials. This microbial polyester, which can be produced in organisms, is an exciting discovery in the field of degradable materials research. It is a material stored in bacteria to cope with food stress. It can be activated by many bacteria, leading to rapid depolymerization.

研究結(jié)果發(fā)現(xiàn), 解聚細菌酶可看成截然不同的兩類, 一類酶將高分子聚合物降解成二聚體, 另一類則把二聚體降解成單體。PHB生物降解的初步是膜表面的改變, 即表面水解, 從而導(dǎo)致表面-OH和~COOH數(shù)量的增加, 細菌開始繁殖, 生長速度取決于溫度與 pH值, PHB終端降解成3一羥基丁酸, 它是人體血液的正常排謝物。

The results showed that the depolymerizing bacterial enzymes could be divided into two types: one type degraded the polymer into dimer, the other type degraded the dimer into monomer. The initial stage of PHB biodegradation is the change of membrane surface, that is, surface hydrolysis, which leads to the increase of the number of - oh and ~ COOH on the surface, and the bacteria begin to reproduce. The growth rate depends on the temperature and pH value. PHB terminal is degraded into 3-hydroxybutyric acid, which is the normal metabolite of human blood.

PHB主要用于一次性餐具、膜及醫(yī)學(xué)應(yīng)用等。英國某公司近期完善了發(fā)酵PHB的提純方法, 基本開始生產(chǎn)PHB。目前有關(guān)一次性餐具廠家正試以PHB合成系統(tǒng)的遺傳因子導(dǎo)入植物中, 以便得到微生物聚酯, 這一實驗已獲得初步成功。某公司用已取得技術(shù), 即重組細胞技術(shù), 生產(chǎn)一種聚羥基烷酸酯的降解材料, 此法較發(fā)酵法成本低。

PHB is mainly used in disposable tableware, membrane and medical applications. A company in the UK has recently improved the purification method of PHB fermentation and basically started to produce PHB. At present, the manufacturers of disposable tableware are trying to introduce the genetic factors of PHB synthesis system into plants in order to obtain microbial polyester. This experiment has been preliminarily successful. A company used the obtained technology, i.e. recombinant cell technology, to produce a kind of degradation material of polyhydroxyalkanoates. The cost of this method is lower than that of fermentation method.

一次性餐具廠家對生物降解研究工作的方向基本有兩個∶

There are two directions for the research on biodegradation of disposable tableware manufacturers

（1）主要是和生物技術(shù)相結(jié)合, 合成出新的具有和天然大分子結(jié)構(gòu)相似的高分子材料, 該過程需要大量人力、物力和時間的投入

(1) It is mainly combined with biotechnology to synthesize new polymer materials with similar structure to natural macromolecules, which requires a lot of manpower, material resources and time investment

（2）放在一次性餐具降解的可控制性上, 經(jīng)處理以后, 一次性餐具則較快分解。處理操作應(yīng)簡單易行, 便于實施。如聚竣酸, 這類高分子在堿性環(huán)境中是穩(wěn)定存在的, 可一旦放入中性或酸性環(huán)境中, 很快就顯明地水解為單體。

(2) The emphasis is placed on the controllability of the degradation of disposable tableware. After treatment, disposable tableware decomposes rapidly. The treatment operation should be simple and easy to implement. For example, polyacid, which is stable in alkaline environment, can be hydrolyzed into monomers quickly and obviously once put into neutral or acidic environment.