title: Grafting-from cellulose nanocrystals via photoinduced Cu-mediated reversible-deactivation radical polymerization.
abstract: In this work we describe the grafting of cellulose nanocrystals (CNCs) by surface-initiated photoinduced Cu-mediated reversible-deactivation radical polymerization (RDRP). Initially, CNCs obtained through sulfuric acid hydrolysis were functionalized with a tertiary bromo-ester moiety as an initiating group for the subsequent RDRP of methyl acrylate, targeting three different degrees of polymerization for the polymer grafts: 50, 300 and 600. The polymerizations proceeded in DMSO in the presence of CuBr2and Me6TREN as the catalytic system utilizing a UV source (λmax≈360nm). The technique proved highly versatile for the modification of CNCs with poly(methyl acrylate), where considerably high grafting was achieved in short reaction times (90min), with simple purification steps. CNC morphology was maintained and polymer grafts were evident through FT-IR spectroscopy, thermal analysis, contact angle measurements, X-ray photoelectron microscopy and x-ray diffraction.
authors.affiliation: KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Fibre and Polymer Technology, Teknikringen 56, SE-100 44 Stockholm, Sweden. Electronic address: f.l.hatton@sheffield.ac.
authors.forename: Fiona L
authors.initials: FL
authors.lastname: Hatton
authors.affiliation: McMaster University, Department of Chemical Engineering, 1280 Main Street West, Hamilton, Ontario L8S 4L7, Canada. Electronic address: kedziosa@mcmaster.ca.
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Kedzior
authors.affiliation: McMaster University, Department of Chemical Engineering, 1280 Main Street West, Hamilton, Ontario L8S 4L7, Canada. Electronic address: ecranst@mcmaster.ca.
authors.forename: Emily D
authors.initials: ED
authors.lastname: Cranston
authors.affiliation: KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Fibre and Polymer Technology, Teknikringen 56, SE-100 44 Stockholm, Sweden. Electronic address: annac@kth.se.
authors.forename: Anna
authors.initials: A
authors.lastname: Carlmark
keywords: Cellulose nanocrystals; Characterization; Nanoparticle compatibilization; Photoinduced polymerization; Polymer-grafted CNC; RDRP