0000000000238546
AUTHOR
Björn Dahlgren
Numerical simulations of the kinetics of pulsed electron beam induced synthesis of nanogels in dilute aqueous polymer solutions
Nanogel can be produced by irradiation of dilute aqueous polymer solutions. The nanogels are formed primarily through intramolecular radical-radical crosslinking reactions between two polymer radical sites.
Numerical Simulation of the Kinetics of Radical Decay in Single-Pulse High-Energy Electron-Irradiated Polymer Aqueous Solutions
A new method for the numerical simulation of the radiation chemistry of aqueous polymer solutions is introduced. The method makes use of a deterministic approach combining the conventional homogeneous radiation chemistry of water with the chemistry of polymer radicals and other macromolecular species. The method is applied on single-pulse irradiations of aqueous polymer solutions. The speciation of macromolecular species accounts for the variations in the number of alkyl radicals per chain, molecular weight, and number of internal loops (as a consequence of an intramolecular radical-radical combination). In the simulations, the initial polymer molecular weight, polymer concentration, and do…
The role of molecular oxygen in the formation of radiation-engineered multifunctional nanogels
Abstract Nanogels are very promising biomedical nanodevices. The classic “radiation chemistry-based” approach to synthetize nanogels consists in the irradiation with pulsed electron beams of dilute, N2O-saturated, aqueous solutions of water-soluble polymers of the “crosslinking type”. Nanogels with controlled size and properties are produced in a single irradiation step with no recourse to initiators, organic solvents and surfactants. This paper combines experimental syntheses, performed with two e-beam irradiation setups and dose-ranges, starting from poly(N-vinyl pyrrolidone) solutions of various concentrations, both in N2O-saturated and air-saturated initial conditions, with the numerica…
Numerical Simulations of Nanogel Synthesis Using Pulsed Electron Beam
In this work, a new method for numerical simulation of the radiation chemistry of aqueous polymer solutions exposed to a sequence of electron pulses is presented. The numerical simulations are based on a deterministic approach encompassing the conventional homogeneous radiation chemistry of water as well as the chemistry of polymer radicals. The multitude of possible reactions in the macromolecular system is handled by allowing for a large number of macromolecular species. The speciation of macromolecular species is done to account for variations in molecular weight, number of alkyl radicals per chain, number of peroxyl radicals per chain, number of oxyl radicals per chain, and number of in…
Understanding generation of multifunctional nanogels in chemical-free e-beam irradation synthesis
Radiation engineered nanogels are the core of very promising theranostic nanodevoces. They can be produced starting from aqueous solutions of chemically inert polymers by pulsed e-beam irradiation.