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Liquid-crystal polymers (LCPs) are a class of aromatic polymers. They are extremely unreactive and inert, and highly resistant to fire. == Background == Liquid crystallinity in polymers may occur either by dissolving a polymer in a solvent (lyotropic liquid-crystal polymers) or by heating a polymer above its glass or melting transition point (thermotropic liquid-crystal polymers).〔Shibaev, Valery P.; Lam, Lui, eds. (1994). ''Liquid Crystalline and Mesomorphic Polymers''. New York: Springer.〕 Liquid-crystal polymers are present in melted/liquid or solid form.〔Callister (2007): "Materials Science and Engineering - An Introduction," 557-558.〕 In solid form the main example of lyotropic LCPs is the commercial aramid known as Kevlar. Chemical structure of this aramid consists of linearly substituted aromatic rings linked by amide groups. In a similar way, several series of thermotropic LCPs have been commercially produced by several companies (e.g., Vectran / Ticona). A high number of LCPs, produced in the 1980s, displayed order in the melt phase analogous to that exhibited by nonpolymeric liquid crystals. Processing of LCPs from liquid-crystal phases (or mesophases) gives rise to fibers and injected materials having high mechanical properties as a consequence of the self-reinforcing properties derived from the macromolecular orientation in the mesophase. Today, LCPs can be melt-processed on conventional equipment at high speeds with excellent replication of mold details. In fact, the high ease of forming of LCPs is an important competitive advantage against other plastics, as it offsets high raw material cost.〔Charles A. Harper, ed., ''Modern Plastics Handbook'', ISBN 0-07-026714-6, 2000.〕 The class of polar and bowlic LCPs, with unique properties and important potential applications, remains to be exploited.〔Lam, Lui (1988). "Bowlic and polar liquid crystal polymers". ''Mol. Cryst. Liq. Cryst''. 155, 531.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Liquid crystal polymer」の詳細全文を読む スポンサード リンク
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