화학공학소재연구정보센터
Polymer(Korea), Vol.23, No.4, 580-586, July, 1999
비이온 계면활성제/소수성 함유 아크릴 아마이드 종중합체에 의한 액정의 분산 안정화
Saabilization of Liquid Crystal Dispersion by Nonionic Surfactant/Acrylamide Copolymer Containing Hydrophobic Moieties
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초록
비이온 계면활성제 (H(OCH2-CH28-OC6H4-C9H19, NP-8)와 소수성 사슬인 nonylphenol groups을 함유하고 있는 acrylamide 공중합체가 액정 (LC)-in-water dispersion에서 액정의 안정성에 미치는 영향을 조사하였다. 흐림점과 흡착 실험에 의하면, NP-8과 nonylphenol 사슬사이에 강한 소수성 상호작용이 발생하였다. 또한 계면활성제를 첨가함으로써 분산된 액정의 안정성과 nematic curvilinear aligned phase (NCAP) 복합필름의 전기광학적 특성이 향상되었다. 이것은 계면활성제가 액정 droplet 주위에 nonpolar microenvironment를 형성하여 결과적으로 액정과 고분자 매트릭스 사이에서 계류효과의 감소에 의한 것임을 알 수 있었다.
The effect of nonionic surfactant (H(OCH2- CH2)8-OC6H4-C9 H19, NP8) and acrylamide copolymer containing nonylphenyl groups as hydrophobic moieties on the stabilization of liquid crystal(LC)-in-water dispersion has been studied. According to cloud point and adsorption measurements, the hydrophobically strong interaction between NP-8 and the nonylphenol moieties is formed. And the addition of surfactant increases the stability of LC dispersion and improves the electrooptical properties of the nematic curvilinear aligned phase(NCAP) compositie film. It is due to the presence of surfactant which allows the formation of nonpolar microenvironment in the round of LC droplet and finally reduces the anchoring effect between LC and polymeric wall.
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