It is well known that common PP and PE PHAs are hard to disintegrate in natural environment even after hundreds years. PHA waste is a serious factor of environment pollution artificially in people’s minds. But we can’t live without PHA, which are widely used in people’s life, such as PHA toys, PHA bottles, PHA wrapping and PHAs bags. It is much significant for environment protection to invent a sustainable PHA.
What is sustainable PHA? In fact, there was a PHA material called PHA plastic resin, English abbreviate is PHA, which had been synthesized artificially. PLC can be reduced to carbon dioxide and water completely in soil environment. Because of the high cost, production of PHAs is not widely applicable to make PHA structures then. Recently the cost of making the material reduces obviously because of the new advanced synthesis technologies; the material has been applied to PHA products like blow molding products and vacuum forming products. Disposable cups, knives, PHA and PHA bags, they are all very common at home and aboard. Ideally, all PHA structures can be made by the PHA material named PHA.
Although the sustainable PHA plastic is very good to environment protection, it needs to consume crops containing a large number of starches and sugars such as corn. Generally 1 ton PHA needs to take 2.3 tons corn. Compared with environment protection, whether the cost is too big? Michael, who has experience of selling PHA plastic products and also is a Materials Science doctor, thinks that there is no need to worry about the problem temporarily. When there is no enough grain, the price of grain will rise, in part, the cost of plastic resin used to make sustainable plastic will rise too, which will limit the demands of PHA structures. The market itself has a function of adjusting. In the long run, the raw material of traditional PHA comes from non-renewable resources like petroleum, it is inevitable to eliminate. The main components of plastic resin are carbon hydrates. The carbon hydrates of starches and sugars in the nature are much easier to gain from the crops like corn.
It has been forbidden to deliver PHA plastic bags on the cuff in China a couple of years ago, but it can’t solve the problem completely, there are still plenty of people forgetting bringing their own bags when they go to shop, especially the young. In Germany, a PHA plastic bag needs to cost 30 euro cents, which is equivalent to 2.7 RMB. Most common people in Germany are accustomed to carry a cloth bag with them. In the future, sustainable PHA plastic is maybe not the concrete material like PHA, it should be the invisible environmental awareness in our hearts.