Kinetics of Core‐Shell Nanoparticle Formation by Two‐Dimensional Nuclear Magnetic Resonance

Abstract

We have studied the kinetics of polymeric nanoparticle formation for poly(styrene-block-4-vinylpyridine) [P(S-b-4-VPy)], chains in a non-selective solvent using 1,4-dibromobutane (DBB) as a cross-linker by means of different nuclear magnetic resonance (NMR) spectroscopy techniques. The kinetic process was followed using (1) H, (13) C, and 2-D Heteronuclear Single Quantum Correlation (HSQC) NMR experiments. The kinetic data obtained from 2-D HSQC and (1) H NMR experiments were in good agreement between them, proving the reliability of the 2-D HSQC NMR technique for the in situ study of the kinetics of core-shell nanoparticle formation. A value of 1.5 × 10(-5) s(-1) was determined for the apparent kinetic constant of the P(S-b-4-VPy)-DBB core-shell nanoparticle formation process.

Influence of Anion Exchange in Self-Assembling of Polymeric Ionic Liquid Block Copolymers

“…Furthermore, in the same group of spectra, a signal at δ = 8.3 ppm corresponding to the proton (NÀCHÀ) of P2VP that was a doublet at low reaction time became a singlet when time of reaction increased. Ruiz de Luzuriaga et al 41 reported similar behavior in the quaternization of poly (4-vinylpyridine). This variation of the spectra was attributed to reduction of mobility of monomeric units during the quaternization reaction.…”

Thermoset Magnetic Materials Based on Poly(ionic liquid)s Block Copolymers

“…Furthermore, the doublet observed at δ = 8.3 ppm corresponding to the proton (N–CH−) of P2VP at short reaction time (or low conversion) became a singlet at longer reaction time (or higher conversion). Ruiz de Luzuriaga et al reported similar behavior during the quaternization of poly(4-vinylpyridine) which was attributed to the mobility reduction of monomeric units after quaternization. 1 H NMR was used to monitor the kinetics of quaternization of poly( 0 ).…”