TITLE:
On Single Compartment Pharmacokinetic Model Systems that Obey Free Radical Copolymerization Kinetics and Multiplicity
AUTHORS:
Kal Renganathan Sharma
KEYWORDS:
Single Compartment Pharmacokinetics; Copolymer Composition; Reactivity Ratios; Multiplicity; State Space Model; n Monomers
JOURNAL NAME:
Journal of Encapsulation and Adsorption Sciences,
Vol.3 No.3,
September
24,
2013
ABSTRACT: This study examines the issues in development of
pharmacokinetic single compartment model for systems that obey free radical
copolymerization kinetics. Copolymer composition as a function of reactivity
ratios of comonomers for well mixed case was derived. For some cases, such as
DEF-AN, diethyl fumarate and acrylonitrile system multiplicity in composition were found. The analysis is extended to n monomers. State space model expressions are used and the QSSA assumption is
stated in state space equation form. Conditions when damped oscillations can be
expected are noted. In addition to multiplicity in product composition, an
account of reactivity ratios and other instances of multi- plicity
were found during the pharmacodynamics of the free radical polymerization
reactions. A careful study of initiated case, thermal case, 1 CSTR and 2 CSTRS
was undertaken and results were presented. Numerical integration techniques
were employed on the desktop computer. Steady state and transient state
conversion for initiated case and thermal case for 1 CSTR and 2 CSTRs were
calculated and plotted in Figures 7-9 and 12.
No multiplicity was found in the thermal case for 1 CSTR in the dynamics of
transient monomer conversion. Multiplicity was found in the initiated case
for 1 CSTR in the dynamics of transient conversion of monomer. The multiplicity was found
in the second CSTR for the case of 2 CSTRs in series. No multiplicity was found
in the case of initiator decay.