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Journal ArticleDOI

Solution Properties of Poly(N-isopropylacrylamide)

M. Heskins, +1 more
- 01 Dec 1968 - 
- Vol. 2, Iss: 8, pp 1441-1455
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TLDR
In this paper, a lower critical solution temperature of poly(N-isopropyl acrylamide was found to be due to an entropy effect, which was attributed to the formation of nonpolar and intermolecular hydrogen bonds.
Abstract
Aqueous solutions of poly(N-isopropyl acrylamide) show a lower critical solution temperature. The thermodynamic properties of the system have been evaluated from the phase diagram and the heat absorbed during phase separation and the phenomenon is ascribed to be primarily due to an entropy effect. From viscosity, sedimentation, and light-scattering studies of solutions close to conditions of phase separation, it appears that aggregation due to formation of nonpolar and intermolecular hydrogen bonds is important. In addition, a weakening of the ordering effect of the water-amide hydrogen bonds as the temperature is raised contributes to the stability of the two-phase system.

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Positively Charged Amphiphilic Polymers Based on Poly(N-isopropylacrylamide): Phase Behavior and Shear-Induced Thickening in Aqueous Solution

TL;DR: The phase behavior and rheological properties of hydrophobically modified copolymers based on a thermosensitive N-isopropylacrylamide backbone are reported in this article.
Journal ArticleDOI

Dual Reversible Self-Assembly of PNIPAM-Based Amphiphiles Formed by Inclusion Complexation

TL;DR: The structure and morphology of the vesicles were characterized by dynamic light scattering (DLS), static light scattering(SLS), SEM, TEM, and AFM as discussed by the authors.
Journal ArticleDOI

Stable monodisperse nanomagnetic colloidal suspensions: An overview

TL;DR: This work focuses on the dispersion of MNPs and colloidal stability, and involves surfactant-coating for steric stability, or surface modifications that results in repulsive electrostatic force.
Journal ArticleDOI

Direct Osmolyte–Macromolecule Interactions Confer Entropic Stability to Folded States

TL;DR: This work discusses poly(N-isopropylacrylamide) (PNiPAM) in water whose folding/unfolding equilibrium shifts toward the folded state in the presence of urea, and proposes a new microscopic mechanism that explains how direct osmolyte-macromolecule interactions confer stability to folded states.
Journal ArticleDOI

Thermoresponsive-polymer-based materials for temperature-modulated bioanalysis and bioseparations

TL;DR: Various types of materials based on thermoresponsive polymers for bioanalysis and bioseparations, e.g., thermoreSponsive chromatography and thermally modulated cell separation are described, potentially useful for various applications in biotechnology and biomedicine.
References
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Mouvement Brownien d'un ellipsoide (II). Rotation libre et dépolarisation des fluorescences. Translation et diffusion de molécules ellipsoidales

TL;DR: In this article, the diffusion of molecules ellipsoidales dissoutes is analyzed in a mouvement brownien d'ensemble (rotation and translation) with respect to a set of molecules.
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