Functional cellulose nanocrystals containing cationic and thermo-responsive polymer brushes. (15th October 2020)

• Record Type: Journal Article
• Authors: Alharthi, Salha; Grishkewich, Nathan; Berry, Richard M.; Tam, Kam C.
• Is Part Of: Carbohydrate polymers. Volume 246(2020)
• Publication Date: 2020-10-15
• Subjects: Cellulose nanocrystals -- Thermo-responsive -- Cationic brushes -- Polyelectrolyte effect -- Salting-out; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2020.116651
• Languages: English
• ISSNs: 0144-8617

Abstract

Graphical abstract: Highlights: Cellulose nanocrystals were modified with temperature responsive polymers. Cationic segments were grafted from the thermo-responsive cellulose nanocrystals. A typical salting-out effect was observed for CNC-POEGMA after the addition of salt. The LCST of CNC-POEGMA-PDMC was tuned by varying the cationic monomer content. The salt-responsiveness of CNC-POEGMA-PDMC copolymers depends on the PDMC content. Abstract: Cationic and thermo-responsive polymer brushes were grafted from the surface of cellulose nanocrystals. Di(ethylene glycol) methyl ether methacrylate (MEO2 MA) and poly(oligoethylene glycol) methyl ether acrylate (OEGMA300 ) and (2-methacryloyloxyethyl) trimethylammonium chloride (DMC) were grafted from cellulose nanocrystals (CNCs) via free radical polymerization. The CNC-g-POEGMA (CP) possessed a tunable lower critical solution temperature (LCST) of about 50 °C, and cloud point measurements confirmed that the LCST of the nanoparticles could be manipulated within the range of 40−47 °C by adjusting the DMC content. The salt effect was also investigated, and the results revealed a typical salting-out effect for the CNC-g-POEGMA after the introduction of KCl. On the other hand, the CNC-g-POEGMA-g-DMC (CPD) copolymers displayed two salt-responsive characteristics; polyelectrolyte effect at lower salt concentrations, followed by the salting-out effect at higher salt concentrations, which is dependent on the DMC content.