Related Experiment Video
Updated: Sep 22, 2025

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Influence of Confinement on the Chain Conformation of Cyclic Poly(N-isopropylacrylamide)
David Magerl1, Martine Philipp1, Ezzeldin Metwalli1
1Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany.
Abstract:
In thin and ultrathin supported films, the conformations of flexible linear polymer chains might be considerably confined, in particular, for film thicknesses smaller than a few times the radius of gyration. For ring polymers in solution or in melt, the radii of gyration are significantly reduced as compared to those of their linear counterparts. We study here the influence of geometrical confinement on the chain conformation of cyclic PNIPAM in silicon-supported films. Measurements are performed by grazing incidence small angle neutron scattering (GISANS). For all films, the component of the radius of gyration parallel to the substrate, Rgc∥, is significantly higher than the unperturbed Rgc determined under theta solvent or melt conditions. We attribute this effect to a preferential selection of stretched PNIPAM ring conformations in thin films and a preferential orientation of macromolecules parallel to the film interfaces with the substrate and air.
More Related Videos
11:42Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
11:34Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
Published on: September 8, 2016
Related Concept Videos
Anionic Chain-Growth Polymerization: Overview
Conformations of Cyclohexane
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
Chair Conformation of Cyclohexane
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
Cationic Chain-Growth Polymerization: Mechanism
Polymer Classification: Stereospecificity
Anionic Chain-Growth Polymerization: Mechanism