title: Characterization of molecular association of poly(2-oxazoline)s-based micelles with various epoxides and diols via the Flory-Huggins theory: a molecular dynamics simulation approach.
abstract: The hydrolytic kinetic resolution (HKR) of epoxides has been performed in a shell-crosslinked micellar (SCM) nanoreactor consisting of amphiphilic triblock copolymers based on poly(2-oxazline)s polymer derivatives with attached Co(iii)-salens to the micelle core. To investigate the effect of the molecular interaction of reactant/product molecules with the SCM nanoreactor on the rate of HKR, we calculated the Flory-Huggins interaction parameters (χ) using the molecular dynamics simulation method. For this, the blend systems were constructed with various compositions such as 15, 45, and 70 wt% of the reactant/product molecules with respect to the polymers such as poly(2-methyl-2-oxazoline) (PMOX), poly(2-(3-butinyl)2-oxazoline) (PBOX), and poly(methyl-3-oxazol-2-yl)pentanoate with Co(iii)-salen (PSCoX). From the χ parameters, we demonstrate that the miscibility of reactants/products with polymers has a strong correlation with the experimental reaction rate of the HKR: phenyl glycidyl ether (Reac-OPh) > epoxyhexane (Reac-C4) > styrene oxide (Reac-Ph) > epichlorohydrin (Reac-Cl). To validate this finding, we also conducted the potential of mean force analysis using steered molecular dynamics simulation for the molecular displacement of Reac-Cl and Reac-OPh through PMOX and PSCoX, revealing that the free energy reduction was greater when Reac-OPh molecule enters the polymer phase compared to Reac-Cl, which agrees with the findings from the χ parameters calculations.
authors.affiliation: School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, Georgia 30332-0100, USA and Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, USA. SeungSoon.Jang@mse.gatech.edu.
authors.forename: Byeong Jae
authors.initials: BJ
authors.lastname: Chun
authors.affiliation: Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, USA.
authors.forename: Marcus
authors.initials: M
authors.lastname: Weck
authors.affiliation: Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, USA. SeungSoon.Jang@mse.gatech.edu and Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Seung Soon
authors.initials: SS
authors.lastname: Jang
mesh_terms: D004852:Epoxy Compounds / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008823:Micelles; D056004:Molecular Dynamics Simulation; D010080:Oxazoles / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D004852:Epoxy Compounds; D008823:Micelles; D010080:Oxazoles; C577913:poly(2-oxazoline)