摘要
采用超声和高压均质两种方式分散的细菌纤维素(BC)悬浮液制备了BC纳米纤维稳定的水包油型Pickering乳液,并考察了纤维用量、pH值和机械分散方式对乳液稳定性的影响.结果表明,乳液的稳定性随纳米纤维用量的增加而增加;碱性条件比酸性条件制备的乳液稳定性高,且在pH=12时达到最高.用高压均质方式分散的BC稳定乳液的效果优于采用超声方式分散的BC的效果,这是由于高压均质后的纤维较短,可以提供更多的纳米纤维稳定乳液.计算结果表明,BC纳米纤维在液体石蜡/水界面上的三相接触角为72.5°,说明BC适合稳定水包油型乳液.
Pickering emulsions(O/W)were stabilized by bacterial cellulose(BC) nanofibers which had been disintegrated by two methods,ultrasonication and high pressure homogenization,corresponding to USBC and HGBC.Influences of fiber content,pH,and disintegration method on the stability of emulsions were investigated.Emulsions prepared with higher loading of BC had better stability;and the BC suspensions with higher pH values gave higher emulsion stability index(ESI),and the ESI reached the highest at pH=12.Since fibers disintegrated from high pressure homogenization were shorter than those from ultrasonication,emulsifying effect of HGBC was better than that of USBC.Nanofibers distributed on the surface of emulsified drops,forming a network,were visualized by SEM.The three-phase contact angle of BC nanofibers on the interface of water and liquid paraffin is calculated to be 73.1°,implying both hydrophilic and lipophilic nature,which renders BC adequate to stabilize O/W emulsions.As a biological origin nanofiber,BC has the potential to substitute conventional surfactants,especially in food,pharmaceutical and biodegradable products.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第6期1475-1482,共8页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21106105)
吉林省科技发展计划项目(批准号:200905136)资助