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• Articles by H. Mark

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Abstract

Natural polymers such as wood, cotton, wool, starch, and rubber have been known and used for a long time even though their composition and structure were unknown. At the beginning of this century systematic efforts were started to analyze these materials, elucidate their molecular pattern, and fit them into the framework of organic chemistry. It was found that they all are characterized by the presence of chain-like molecules with very high molecular weights ranging from 10000 to several millions. It was also found that these chains can be oriented by mechanical deformations and assume a laterally ordered crystal-like supermolecular arrangement. As soon as these facts become known as systematic search for synthetic counterparts of natural polymers was started which led to the laboratory preparation and large scale production of many synthetic materials which cover a wide range of properties and applications and which are becoming an increasingly important factor in science and industry. With growing understanding and know-how it also became possible to synthesize polymers with biochemically interesting properties such as the polyelectrolytes and other biopolymers.