title: Characterization of carbon nanofiber mats produced from electrospun lignin-g-polyacrylonitrile copolymer.
abstract: The graft copolymerization of acrylonitrile (AN) onto methanol-soluble kraft lignin (ML) was achieved through a two-step process in which AN was first polymerized with an α,α'-azobisisobutyronitrile initiator, followed by radical coupling with activated ML. A carbon nanofiber material was obtained by electrospinning a solution of this copolymer in N,N-dimethylformamide, then subjecting it to a heat treatment including thermostabilization at 250°C and subsequent carbonization at 600-1400°C. Increasing the carbonization temperature was found to increase the carbon content of the resulting carbon nanofibers from 70.5 to 97.1%, which had the effect of increasing their tensile strength from 35.2 to 89.4 MPa, their crystallite size from 13.2 to 19.1 nm, and their electrical conductivity from ∼0 to 21.3 Scm(-1). The morphology of the mats, in terms of whether they experienced beading or not, was found to be dependent on the concentration of the initial electrospinning solution. From these results, it is proposed that these mats could provide the basis for a new class of carbon fiber material.
authors.affiliation: Division of Wood Chemistry & Microbiology, Korea Forest Research Institute, 57 Hoegiro, Dongdaemun-gu, Seoul 130-712, Republic of Korea.
authors.forename: Won-Jae
authors.initials: WJ
authors.lastname: Youe
authors.affiliation: Division of Wood Chemistry & Microbiology, Korea Forest Research Institute, 57 Hoegiro, Dongdaemun-gu, Seoul 130-712, Republic of Korea.
authors.forename: Soo-Min
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Division of Wood Chemistry & Microbiology, Korea Forest Research Institute, 57 Hoegiro, Dongdaemun-gu, Seoul 130-712, Republic of Korea.
authors.forename: Sung-Suk
authors.initials: SS
authors.lastname: Lee
authors.affiliation: Department of Forest Biomaterials Engineering, College of Forest and Environment Sciences, Kangwon National University, Chuncheon 200-701, Republic of Korea.
authors.forename: Seung-Hwan
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Division of Wood Chemistry & Microbiology, Korea Forest Research Institute, 57 Hoegiro, Dongdaemun-gu, Seoul 130-712, Republic of Korea. Electronic address: yongsikk@korea.kr.
authors.forename: Yong Sik
authors.initials: YS
authors.lastname: Kim
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D006358:Hot Temperature; D008031:Lignin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry
chemical_list: D000180:Acrylic Resins; D011108:Polymers; C010504:polyacrylonitrile; D002244:Carbon; D008031:Lignin
keywords: Carbon nanofibers; Copolymerization; Electrospinning; Lignin