Jump to main content
Jump to site search


Molecular weight and uniformity define the mechanical performance of lignin-based carbon fiber

Author affiliations

Abstract

Lignin-based carbon fiber represents a renewable and low-cost alternative to petroleum-based carbon fiber. However, the poor mechanical performance of current lignin carbon fiber hinders its application. We hypothesized that the lower optimal mechanical performance is caused by the inherent heterogeneity of lignin. It is still unknown how the molecular weights (MWs) and lignin uniformity will impact the performance of lignin carbon fiber. We thereby addressed this hypothesis by fractionating lignin into fractions with different MWs and polydispersity indices (PDIs). An enzyme–mediator-based method and a dialysis method were developed to derive lignin fractions with increased MW and decreased PDI. Lignin fractions were electro-spun into fibers after blending with polyacrylonitrile (PAN) at 1 : 1 (w/w) ratio. The fractionation in general improved the spinnability of lignin to allow us to obtain finer lignin-based carbon fibers. The elastic modulus of lignin carbon fibers, as measured by nanoindentation, was increased as the lignin MW increased and as PDI decreased. The scatter plot and linear regression revealed very good correlation between the elastic modulus and PDI, as well as certain correlation between the elastic modulus and MW. XRD and Raman spectroscopy revealed that the crystallite size and the content of the pre-graphitic turbostratic carbon increased with higher lignin MW and lower PDI, revealing the mechanism of the improvement in carbon fiber mechanical performance. This study elucidated the impacts of lignin MW and uniformity on the mechanical properties of carbon fiber, and could thus guide the development of lignin processing technologies for quality lignin-based carbon fiber.

Graphical abstract: Molecular weight and uniformity define the mechanical performance of lignin-based carbon fiber

Back to tab navigation

Supplementary files

Publication details

The article was received on 07 Feb 2017, accepted on 31 May 2017 and first published on 31 May 2017


Article type: Communication
DOI: 10.1039/C7TA01187C
Citation: J. Mater. Chem. A, 2017, Advance Article
  •   Request permissions

    Molecular weight and uniformity define the mechanical performance of lignin-based carbon fiber

    Q. Li, W. K. Serem, W. Dai, Y. Yue, M. T. Naik, S. Xie, P. Karki, L. Liu, H. Sue, H. Liang, F. Zhou and J. S. Yuan, J. Mater. Chem. A, 2017, Advance Article , DOI: 10.1039/C7TA01187C

Search articles by author

Spotlight

Advertisements