• Title/Summary/Keyword: dicarboxylic acid chlorides

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Cholesteric Gels form Hydroxypropyl Cellulose(HPC) : Effect of Molecular Characteristics of HPC and Crosslinking Agent on Cholesteric Pitch and Swelling Behavior (Hydroxypropyl Cellulose (HPC)를 이용하여 제조한 Cholesteric Gels : HPC와 가교제의 분자특성이 Cholesteric Pitch와 팽윤거동에 미치는 영향)

  • Kim, Kyung-Hee;Jeong, Seung-Yong;Ma, Yung-Dae
    • Polymer(Korea)
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    • v.25 no.4
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    • pp.545-557
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    • 2001

  • The crosslinked films retaining cholesteric liquid-crystalline order were prepared by casting the liquid crystalline solutions of hydroxypropyl cellulose (HPC) in methanol with the two kinds of aliphatic dicarboxylic acid chlorides (succinyl chloride and suberoyl chloride). The temperature dependence on the cholesteric pitch of the crosslinked films and the swelling behavior of the films in both water and methanol were investigated. The films displayed fingerprint patterns charateristic of cholesteric liquid-crystalline phase, and their pitches, as well as HPC itself, increased with temperature. However, the pitch of all crosslinked samples was much greater than that of HPC at the same temperature and increased with increasing concentration and chain length of the crosslinker. The crosslinked samples exhibited an anisotropic swelling in both solvents. The degree of anisotropy slightly depended on the solvent and crosslinker species, but hardly on the crosslinker concentration investigated.

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