TY - JOUR
T1 - Study on the stability of N-(isopropylacrylamide) in the inverse emulsion using different solvents as the continuous phase
AU - Li, Xinrui
AU - Ge, Zhongwei
AU - Yang, Hongjun
AU - Jiang, Qimin
AU - Jiang, Bibiao
AU - Komarneni, Sridhar
AU - Huang, Wenyan
N1 - Publisher Copyright:
© 2025 Elsevier B.V.
PY - 2026/2/20
Y1 - 2026/2/20
N2 - Water-soluble monomer NIPAM was synthesized to obtain PNIPAM particles with controlled morphology and high molecular weight using inverse emulsion polymerization. Inverse emulsions are generally less stable than traditional emulsions, making the investigation of stable inverse emulsion systems crucial for the successful preparation of polymers. The stability of inverse emulsions formed by aromatic and aliphatic oil phases varies significantly under different conditions. After comparing the effects of various oil phases on the stability of N-(isopropylacrylamide) (NIPAM) emulsions, aliphatic liquid paraffin and aromatic liquid anisole were selected as the oil phases. Two types of inverse emulsions were prepared using a composite emulsifier formed by mixing Span 85 and Tween 80. This study investigated the effects of various factors, including the hydrophilic-lipophilic balance (HLB) value, water-oil volume ratio, temperature, and monomer concentration of different composite emulsifiers on emulsion performance. The type of emulsion was judged by the phase dilution method and the conductivity method, while emulsion stability was evaluated through centrifugal coefficient analysis. Different experimental conditions exhibited distinct effects on the two types of inverse emulsions with varying oil phases. Our research has demonstrated that liquid paraffin exhibited superior stability when utilized as the oil phase in NIPAM inverse emulsion. When the HLB of the emulsifier blend is 4.4, the emulsion temperature is maintained at 25°C, and the volume fraction of the oil phase reaches 80 vol% while the centrifugal stability of the emulsion surpasses 90 %. Furthermore, increase in N-(isopropylacrylamide) concentration and Na2SO4 concentration was found to decrease the stability of both inverse emulsions using different oils, however, this decline was notably more pronounced in anisole-based formulations compared to those utilizing liquid paraffin.
AB - Water-soluble monomer NIPAM was synthesized to obtain PNIPAM particles with controlled morphology and high molecular weight using inverse emulsion polymerization. Inverse emulsions are generally less stable than traditional emulsions, making the investigation of stable inverse emulsion systems crucial for the successful preparation of polymers. The stability of inverse emulsions formed by aromatic and aliphatic oil phases varies significantly under different conditions. After comparing the effects of various oil phases on the stability of N-(isopropylacrylamide) (NIPAM) emulsions, aliphatic liquid paraffin and aromatic liquid anisole were selected as the oil phases. Two types of inverse emulsions were prepared using a composite emulsifier formed by mixing Span 85 and Tween 80. This study investigated the effects of various factors, including the hydrophilic-lipophilic balance (HLB) value, water-oil volume ratio, temperature, and monomer concentration of different composite emulsifiers on emulsion performance. The type of emulsion was judged by the phase dilution method and the conductivity method, while emulsion stability was evaluated through centrifugal coefficient analysis. Different experimental conditions exhibited distinct effects on the two types of inverse emulsions with varying oil phases. Our research has demonstrated that liquid paraffin exhibited superior stability when utilized as the oil phase in NIPAM inverse emulsion. When the HLB of the emulsifier blend is 4.4, the emulsion temperature is maintained at 25°C, and the volume fraction of the oil phase reaches 80 vol% while the centrifugal stability of the emulsion surpasses 90 %. Furthermore, increase in N-(isopropylacrylamide) concentration and Na2SO4 concentration was found to decrease the stability of both inverse emulsions using different oils, however, this decline was notably more pronounced in anisole-based formulations compared to those utilizing liquid paraffin.
UR - https://www.scopus.com/pages/publications/105023670531
UR - https://www.scopus.com/pages/publications/105023670531#tab=citedBy
U2 - 10.1016/j.colsurfa.2025.139151
DO - 10.1016/j.colsurfa.2025.139151
M3 - Article
AN - SCOPUS:105023670531
SN - 0927-7757
VL - 731
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
M1 - 139151
ER -