Common plastics for bioplastics
Biological self destruction plastics are widely used in medicine. In the operation of the fracture, it acts as a support between the bones. As the bones heal, they break down gradually. Doctors usually use stainless steel nuts and screws to treat broken fractures. The splint and the drill hold the broken bones together. The disadvantage of this method is that two operations are performed, one is to implant the stainless steel material, and the other is to remove them. Scientists in Holland have invented a plastic that has been implanted in the body for about two years and then decomposes itself into carbon dioxide and water. There is also a linear biological self destruct plastic that can replace the traditional medical surgical line to suture the wound. This plastic surgical line can be gradually absorbed by the body, eliminating the pain of removing stitches. In addition, a capsule made from self destruct plastic will slowly dissolve in the body and control the speed at which the drug enters the blood vessel. A new type of biological plastics developed in Shanghai. The heat resistance is greatly improved, the heat distortion temperature more than 100 DEG C, and can be widely used for disposable tableware, disposable medical supplies, disposable instruments, electronic devices and other products packaging, and agricultural films, chemical pesticides and fertilizers and other agricultural field release material.
The German microbiologist at University of Gottingen through specific genetic isolation of a bacterium, make plant cells internally generated by this kind of polyester, polyester, can be made of plant biochemical plastic. This kind of plastic breaks down into water and carbon dioxide under the action of bacteria, so this kind of plastic waste can be returned to nature as a plant fertilizer. Japan Industrial Technology Research Institute of scientific and technical personnel in agricultural and forestry waste, such as beans made of biodegradable agricultural film. Some scientists are experimenting with adding starch material in plastics, such as starch food bacteria phagocytosis, so as to make it disappear.
Large computer to TV frame, frame, small ornaments, small kitchen garbage bags, bio plastic figure can be found everywhere. Chemical plastic products bring a variety of convenience to mankind, but also bring people unimaginable trouble. Because some waste plastics will not degrade under natural conditions, combustion will release harmful gases, which will cause pollution to the ecological environment. Therefore, scientists in various countries have begun to develop self destruction or self degradable plastics to solve this problem. Some call it green plastic. Companies in many countries have launched their own bio destruct plastics. The United States Micigen University biologist first proposed the idea of planting plastic. They use potatoes and corn as raw materials to implant genetic genes for plastics so that they can grow under artificial control without harmful components. The American imperial chemical forest corporation uses bacteria to make biodegradable plastics from sugar and organic acids. The process is similar to the fermentation process for producing ethanol. The difference is that the bacteria used are Alcaligenes spp., which convert the feeding substance into a plastic, called PHBV. Bacteria accumulate this plastic as a store of energy, just as humans and animals store fat. When the bacteria stored PHBV reach 80% of their weight, they break through the steam and collect the plastic. PHBV has the same properties as polypropylene, which is stable even after being wasted, but in the case of microorganisms, it is degraded to carbon dioxide and water.
