CAJ | 학술논문

在不同浓度和pH值下，考察了羟丙基甲基纤维素（HPMC）粉末在水表面的动态接触角以及HPMC溶液在气-液、油-水界面的表面张力．结果表明：HPMC粉末的润湿性不强，且受pH值的影响不大，当pH＝4．00时，接触角最低为86．380°；无论在气-液界面还是在油-水界面，表面张力主要取决于界面区域的HPMC 分子链构象变化，这与溶液pH值和溶液浓度有关；质量浓度为0．1％的HPMC溶液，气-液界面的表面张力随pH值增大而增大，质量浓度为0．3％～1．0％的HPMC溶液，气-液界面的表面张力随pH增大呈“∨”形变化，说明界面区域的HPMC分子链构象变化复杂；油-水界面的HPMC与界面上的油脂分子相互作用，使得HPMC分子链构象变化更为复杂；当pH≥6．00时，油-水界面的表面张力随pH值增大而减小，而在pH＜6．00时，浓度的影响更大，油-水界面的表面张力上下波动．
재불동농도화pH치하，고찰료간병기갑기섬유소（HPMC）분말재수표면적동태접촉각이급HPMC용액재기-액、유-수계면적표면장력．결과표명：HPMC분말적윤습성불강，차수pH치적영향불대，당pH＝4．00시，접촉각최저위86．380°；무론재기-액계면환시재유-수계면，표면장력주요취결우계면구역적HPMC 분자련구상변화，저여용액pH치화용액농도유관；질량농도위0．1％적HPMC용액，기-액계면적표면장력수pH치증대이증대，질량농도위0．3％～1．0％적HPMC용액，기-액계면적표면장력수pH증대정“∨”형변화，설명계면구역적HPMC분자련구상변화복잡；유-수계면적HPMC여계면상적유지분자상호작용，사득HPMC분자련구상변화경위복잡；당pH≥6．00시，유-수계면적표면장력수pH치증대이감소，이재pH＜6．00시，농도적영향경대，유-수계면적표면장력상하파동．
The dynamic contact angle of hydroxypropyl methylcellulose (HPMC)powders on water surface,as well as the air-water and the oil-water surface tensions of HPMC aqueous solution,were investigated at different concen-trations and pH values.The results show that (1 )the wettability of HPMC powders is not strong enough and is slightly affected by the pH value;(2)the contact angle reaches its minimum 86.380°at pH 4.00;(3)the sur-face tension of HPMC aqueous solution mainly depends on the change of molecular chain conformation in the inter-facial area and varies with both the pH value and the concentration;(4 )the air-water surface tension increases with the pH value at the mass concentration of 0.1%and shows a V-shaped variation with the pH value at the mass concentration ranging from 0.3%to 1 .0%,which illustrates the complex change of HPMC molecular chain confor-mation in the interfacial area;(5 )the conformation of HPMC molecular chains becomes more complex at the oil-water interface due to the interaction between HPMC and the lipid in the oil;and (6)the oil-water surface tension decreases with the increase of pH value that is not less than 6.00,and varies irregularly due to the greater effect of concentration when the pH value is less than 6.00.