Preparation of a Thermoplastic Lignin-Based Biomaterial through Atom Transfer Radical Polymerization

Abstract

Journal of Wood Chemistry and TechnologyPublication details, including instructions for authors and subscription information:Graft copolymerization of styrene onto kraft lignin (KL) was achieved by atom transfer radical polymerization (ATRP) using a fully substituted lignin-based macroinitiator (KLM). The number average of molecular mass (M n ) of polystyrene copolymer graft side-chains was achieved by varying the ratio of the DMF: water solvent system from 5:0 to 1:4. A M n of up to ∼206,000 was obtained using a DMF/water ratio of 3:2 (v/v). However, as the M n increased, the overall ATRP became less controlled. In addition, the thermal properties of the lignin-g-polystyrene copolymers improved significantly with increasing M n of polystyrene copolymer side-chains.

Synthesis and characterization of kraft lignin-graft-polylactide copolymers

“…The molecular weights of the MeKL-g-PLA copolymers (M n ; 1,100,000-9,000,000 g/mol) were significantly higher than that of neat MeKL. When the molecular weight of the Cl-PLA samples used for copolymerization was increased, the size of the MeKL-g-PLA copolymers decreased, but the final yield of MeKL-g-PLA copolymers was increased from 25.6 to 31.2 g. This was likely because a smaller molecular mass of Cl-PLA could be more easily grafted either at phenolic or aliphatic hydroxyl groups of MeKL due to accessibility by length of Cl-PLA chain even if the acylation of both phenolic and aliphatic hydroxyl groups in lignin could be widely achieved in the presence of pyridine solvent system (Kim et al 2015). Thus, it is concluded that copolymerization of PLA onto MeKL occurred randomly at the sites of either phenolic or aliphatic hydroxyl groups.…”

“…The KL used in this study constituted 93.1 % Klason lignin content, composed of 87.2 % of insoluble lignin and 5.9 % of acid-soluble lignin according to previous Wood Sci Technol studies (Kim and Kim 2013;Kim et al 2015). However, KL was poorly soluble in most organic solvent, so MeKL, relatively low molecular weight compared to that of KL, was isolated from KL in order to increase the solvent solubility for the graft copolymerization of PLA onto lignin.…”

“…KL was isolated from the black liquor according to the method described by Kim et al (2015). The pH of the black liquor was adjusted to approximately 2.0 using concentrated HCl.…”

Characterization Of C60/Bi2TiO4F2 as a Potential Visible Spectrum Photocatalyst for The Depolymerization of Lignin

“…[6] Thus, depolymerizing lignin to produce small molecules of aromatics is an alluring route, and developing a highly efficient method of depolymerization is urgently needed. However, lignin depolymerization is challenging given the special structure and properties, such as complex network of phenylpropane units [7] and hydrophobicity. [8] Numerous studies have been devoted to production of fuel or high-value-added chemicals using lignin through various methods, such as solvolysis including hydrolysis, [9] hydrogenolysis, [10] pyrolysis, [11] and catalytic oxidation.…”

Electrochemical Characteristics of Supercapacitor Electrode Using MnO2Electrodeposited Carbon Nanofiber Mats from Lignin-g-PAN Copolymer

“…최근 친환경 소재 개발의 필요성이 대두됨에 따라 리 그닌으로부터 화학약품, 플라스틱 및 탄소섬유 소재화 원료 등으로 이용하기 위한 바이오리파이너리 연구가 많은 관심을 받고 있다 (Gordobil, 2014;Kim and Kim, 2013;Norberg et al, 2013). 이런 관점에서 이 전 연구에서 크라프트 리그닌을 Polyacrylonitrile (PAN)과 함께 그라프팅 중합법을 사용하여 공중합 체를 제조하였고, 전기방사와 열처리를 통해 제조한 리그닌-g-PAN 공중합체 기반의 탄소나노섬유 매트 (carbon nanofiber mat from lignin-g-PAN copolymer, LCNFM)를 제조하였다 (Youe et al, 2016;Kim et al, 2015). NiO, VO x , CuO 등의 전이 금속 산화물이 이용되고 있다 (Huang et al, 2014;Dubal et al, 2013;Zhao et al, 2012;Zhang et al, 2012;Qu et al, 2012;Xia et al, 2011) …”