The effect of chitosan molecular weight on CO2-triggered switching between emulsification and demulsification

Ren, Dongyin1; Shang, Zhixin1; Zhang, Mei1; Xu, Shengming2; Xu, Zhenghe2,3

2021-09-01

10.1039/d1sm01036k

Soft Matter   影响因子和分区

1744-683X

1744-6848

The role of molecular weight as a key physical property of macromolecules in determining the CO2-triggered switching characteristics of responsive emulsions prepared using CO2-switchable macromolecules has not been studied and is the focus of the current study. In this work, CO2-switchable chitosan of four different molecular weights is used to investigate the effect of molecular weight on CO2-triggered switching of CO2-responsive emulsions. The molecular weight of chitosan is shown to have an opposite effect on emulsification and demulsification by the CO2 trigger. Before bubbling of CO2, chitosan of higher molecular weight forms a more stable three-dimensional network structure in the continuous phase of oil-in-water (O/W) emulsions, which leads to the formation of a more stable emulsion. After bubbling of CO2, the chitosan of higher molecular weight makes the continuous phase more viscous, which leads to an incomplete demulsification as compared with the chitosan of lower molecular weight. Experimental evidence from the measurement of conductivity, interfacial tension and rheological properties is provided to support the proposed mechanism. This work is of great significance in guiding the selection of desirable CO2-switchable polymers for switchable emulsions of desired switching characteristics.

SCI ; EI

英语

通讯

National Natural Science Foundation of China[21938003] ; Zhujiang Talent Program of Guangdong Province[K17253301] ; Shenzhen Science and Technology Innovation Commission[ZDSYS20200421111401738]

Chemistry ; Materials Science ; Physics ; Polymer Science

Chemistry, Physical ; Materials Science, Multidisciplinary ; Physics, Multidisciplinary ; Polymer Science

WOS:000702490300001

ROYAL SOC CHEMISTRY

20214411103948

Bubble formation ; Chitosan ; Demulsification ; Emulsification ; Macromolecules ; Molecular weight ; Ostwald ripening ; Switching

Gas Dynamics:631.1.2 ; Chemical Operations:802.3 ; Organic Compounds:804.1 ; Inorganic Compounds:804.2 ; Polymeric Materials:815.1 ; Atomic and Molecular Physics:931.3

Web of Science

1.Dezhou Univ, Coll Text & Clothing, Dezhou 253023, Peoples R China
2.Tsinghua Univ, Inst Nucl & New Energy Technol, Beijing 100084, Peoples R China
3.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen Key Lab Interfacial Sci & Engn Mat, Shenzhen 518055, Peoples R China

Ren, Dongyin,Shang, Zhixin,Zhang, Mei,et al. The effect of chitosan molecular weight on CO2-triggered switching between emulsification and demulsification[J]. Soft Matter,2021,17:9332-9338.

Ren, Dongyin,Shang, Zhixin,Zhang, Mei,Xu, Shengming,&Xu, Zhenghe.(2021).The effect of chitosan molecular weight on CO2-triggered switching between emulsification and demulsification.Soft Matter,17,9332-9338.

Ren, Dongyin,et al."The effect of chitosan molecular weight on CO2-triggered switching between emulsification and demulsification".Soft Matter 17(2021):9332-9338.