Prediction of phase separation during the drying of polymer shells
Abstract
During the drying of polymer shells formed by microencapsulation, vacuole formation is believed to occur as a result of phase separation. To better understand and control this process, we have used a multicomponent diffusion formalism to predict compositional changes in the layer as organic solvents diffuse out and water diffuses into the layer. Formation of thermodynamically unstable compositions can lead to phase separation by condensation of water on submicron foreign particles present in the shell wall. We used statistical mechanics, the UNIFAP methodology, and empirical data to deduce the required values of transport coefficients and equilibrium phase compositions. The results suggest that vacuole formation can be eliminated or reduced by removing submicron and larger particles from the shell wall and by using solvents with lower intrinsic water solubilities. 21 refs., 7 figs.
- Authors:
-
- Lawrence Livermore National Lab., CA (United States)
- Soane Technologies Inc., Hayward, CA (United States)
- Publication Date:
- OSTI Identifier:
- 171417
- DOE Contract Number:
- W-7405-ENG-48; AC03-91SF18601
- Resource Type:
- Journal Article
- Journal Name:
- Fusion Technology
- Additional Journal Information:
- Journal Volume: 28; Journal Issue: 5; Other Information: PBD: Dec 1995
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; 70 PLASMA PHYSICS AND FUSION; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; SHELLS; DRYING; SOLUTIONS; THERMODYNAMICS; POLYMERS; TARGETS; INERTIAL CONFINEMENT; IMPACT FUSION; POLYSTYRENE; MATHEMATICAL MODELS; MASS TRANSFER
Citation Formats
Wilemski, G, Cook, R, Boone, T, Cheung, L, and Nelson, D. Prediction of phase separation during the drying of polymer shells. United States: N. p., 1995.
Web.
Wilemski, G, Cook, R, Boone, T, Cheung, L, & Nelson, D. Prediction of phase separation during the drying of polymer shells. United States.
Wilemski, G, Cook, R, Boone, T, Cheung, L, and Nelson, D. 1995.
"Prediction of phase separation during the drying of polymer shells". United States.
@article{osti_171417,
title = {Prediction of phase separation during the drying of polymer shells},
author = {Wilemski, G and Cook, R and Boone, T and Cheung, L and Nelson, D},
abstractNote = {During the drying of polymer shells formed by microencapsulation, vacuole formation is believed to occur as a result of phase separation. To better understand and control this process, we have used a multicomponent diffusion formalism to predict compositional changes in the layer as organic solvents diffuse out and water diffuses into the layer. Formation of thermodynamically unstable compositions can lead to phase separation by condensation of water on submicron foreign particles present in the shell wall. We used statistical mechanics, the UNIFAP methodology, and empirical data to deduce the required values of transport coefficients and equilibrium phase compositions. The results suggest that vacuole formation can be eliminated or reduced by removing submicron and larger particles from the shell wall and by using solvents with lower intrinsic water solubilities. 21 refs., 7 figs.},
doi = {},
url = {https://www.osti.gov/biblio/171417},
journal = {Fusion Technology},
number = 5,
volume = 28,
place = {United States},
year = {Fri Dec 01 00:00:00 EST 1995},
month = {Fri Dec 01 00:00:00 EST 1995}
}