著者

Bashir Nabil H H

出版者

Graduate School of Veterinary Medicine, Hokkaido University

雑誌

Japanese Journal of Veterinary Research (ISSN:00471917)

巻号頁・発行日

vol.61, no.Supplement, pp.S1-S11, 2013-02

被引用文献数

4

---

Plastics are a subspecies of a class of materials known as polymers. These are composed of large molecules, formed by joining many, often thousands, of smaller molecules (monomers) together. Plastics are made from low-molecular-weight monomer precursors, organic materials, which are mostly derived from petroleum, that are joined together by a process called “polymerization.” Plastics owe their name to their most important property, the ability to be shaped to almost any form to produce articles of practical value. Plastics can be stiff and hard or flexible and soft. Because of their light weight, low cost, and desirable properties, their use has rapidly increased and they have replaced other materials, e.g. metals and glass. Plastics are used in millions of items, including cars, bulletproof vests, toys, hospital equipment, and food containers. More than a 40 billion kg of plastic were produced in 2000. Their increased use has resulted in concern with (1) the consumption of natural resources such as oil, (2) the toxicity associated with their manufacture and use, and (3) the environmental impact arising from discarded plastics.