Imidazolium end-functionalized poly(L-lactide) for efficient carbon nanotube dispersion

ArticleinChemical Communications 46(30):5527-9 · August 2010with11 Reads
DOI: 10.1039/c0cc00920b · Source: PubMed
Poly(l-lactide) end-functionalized by an imidazolium ring was synthesized by ring-opening polymerization of l-lactide from a hydroxylated ionic liquid. When challenged with CNTs in solution, this polyester exhibited significant binding ability towards the nanotube surface with respect to omega-pyrene poly(l-lactide).
    • "Based on previous findings, a concentration of 4 wt% of py-end-PLLA of 24 900 g mol −1 was shown to be optimal to disperse the MWCNTs in the PLLA matrix [29]. As demonstrated in table 3 andfigure 4, the addition of MWCNT to PLLA/py-end-PLLA brought a substantial enhancement in the tensile modulus and decrease in elongation at the break for all analyzed samples. "
    [Show abstract] [Hide abstract] ABSTRACT: In order to improve the mechanical properties of poly(L-lactide) (PLLA) based implants, a study was made of how far well dispersed multi-walled carbon nanotubes (MWCNTs) within a PLLA matrix were able to positively affect these properties. To this end, pyrene-end-functionalized poly(L-lactide) (py-end-PLLA) was evaluated as a dispersing agent. Transmission electron microscopy (TEM) analyses and mechanical tests of MWCNTs-based materials demonstrated an enhancement of MWCNT dispersion in the PLLA matrix and improved Young's modulus (E) when 4 wt% of py-end-PLLA was used as the dispersing agent. Subsequently, the bioacceptance of PLLA/py-end-PLLA/MWCNTs nanocomposites was evaluated using human bone marrow stromal cells (HBMC) in vitro. The inclusion of py-end-PLLA and MWCNTs supported HBMC adhesion and proliferation. The expression levels of the bone-specific markers indicated that the cells kept their potential to undergo osteogenic differentiation. The results of this study indicate that the addition of MWCNT combined with py-end-PLLA in PLLA/py-end-PLLA/MWCNTs nanocomposites may widen the range of applications of PLLA within the field of bone tissue engineering thanks to their mechanical strength and cytocompatibility.
    Full-text · Article · Aug 2015
    • "Mecerreyes et al. [156] directly used poly(VeimBr) to stably disperse SWCNTs in solvents. In the work reported by Dubios et al. [157], an imidazolium end-functionalized poly(L-lactide) (Imi-PLLA) was synthesized by ring-opening polymerization of L-lactide in the presence of a hydroxylated IL as an initiator, and then was used to assist dispersion of MWCNTs into chloroform. The homogeneous suspension of MWCNTs exists over a period of about two months, due to the high binding ability of imidazolium moieties of Imi-PLLA with the conjugated surface of MWCNTs. "
    [Show abstract] [Hide abstract] ABSTRACT: Carbon nanotubes (CNTs) and graphene sheets are the most promising fillers for polymer nanocomposites due to their superior mechanical, electrical, thermal optical and gas barrier properties, as well as high flame-retardant efficiency. The critical challenge, however, is how to uniformly disperse them into the polymer matrix to achieve a strong interface for good load transfer between the two. This problem is not new but more acute in CNTs and graphene, both because they are intrinsically insoluble and tend to aggregate into bundles and because their surfaces are atomically smooth. Over the past decade, imidazolium ionic liquids (Imi-ILs) have played a multifunctional role (e.g., as solvents, dispersants, stabilizers, compatibilizers, modifiers and additives) in the fabrication of polymer composites containing CNTs or graphene. In this review, we first summarize the liquid-phase exfoliation, stabilization, dispersion of CNTs and graphene in Imi-ILs, as well as the chemical and/or thermal reduction of graphene oxide to graphene with the aid of Imi-ILs. We then present a full survey of the literature on the Imi-ILs assisted fabrication of CNTs and graphene-based nanocomposites with a variety of polymers, including fluoropolymers, hydrocarbon polymers, polyacrylates, cellulose and polymeric ionic liquids. Finally, we give a future outlook in hopes of facilitating progress in this emerging area.
    Full-text · Article · Jun 2013
  • [Show abstract] [Hide abstract] ABSTRACT: Luminescent carbon-based materials have been prepared by electrostatic self-assembly of negatively-charged luminescent Eu(III)-complex with imidazolium-functionalized MWCNTs.
    Full-text · Article · Feb 2011
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