Premium
A Practical Approach to Reaction Calorimetry in Presence of Supercritical Vinylidene Fluoride
Author(s) -
MéndezEcoscia Ana C.,
SheibatOthman Nida,
McKenna Timothy F. L.
Publication year - 2016
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.201600084
Subject(s) - supercritical fluid , reaction calorimeter , calorimetry , materials science , thermodynamics , polymerization , heat transfer , polymer , reaction rate , chemical engineering , polymer chemistry , chemistry , organic chemistry , composite material , physics , engineering , catalysis
Summary A practical approach was implemented to follow the kinetics of the polymerization of supercritical vinylidene fluoride via emulsion polymerization using reaction calorimetry on a 4L laboratory scale reactor, in batch and semi‐batch mode. The heat flow term was studied by determining the dynamic evolution of the system under both non‐reactive and reactive conditions. Simultaneous estimations of the evolution of overall heat transfer coefficient and heat of reaction were determined using a high‐gain nonlinear cascade state estimator. Estimation strategy and hypotheses were validated by comparing the reaction rates obtained independently by calorimetry on the one hand and direct measurement of monomer consumption on the other. It was shown that while the presence of supercritical fluid in the head space led to some unexpected variation of the overall heat transfer coefficient, the method proposed here is robust enough that accurate values of the heat flow were obtained under all conditions.