Structural Changes of Bagasse dusring the Homogeneous Esterification with Maleic Anhydride in Ionic Liquid 1-Allyl-3-methylimidazolium Chloride

Huihui Wang; Wei Chen; Xueqin Zhang; Yi Wei; Aiping Zhang; Shijie Liu; Xiaoying Wang; Chuanfu Liu

doi:10.3390/polym10040433

Structural Changes of Bagasse dusring the Homogeneous Esterification with Maleic Anhydride in Ionic Liquid 1-Allyl-3-methylimidazolium Chloride

Polymers (Basel). 2018 Apr 13;10(4):433. doi: 10.3390/polym10040433.

Authors

Huihui Wang¹, Wei Chen², Xueqin Zhang³, Yi Wei⁴, Aiping Zhang⁵, Shijie Liu^{6

7}, Xiaoying Wang⁸, Chuanfu Liu⁹

Affiliations

¹ State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. wang.huihui@mail.scut.edu.cn.
² State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. geogeo_chen@163.com.
³ State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. xueqin0228@gmail.com.
⁴ State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. fewvergil@mail.scut.edu.cn.
⁵ College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China. aiping@scau.edu.cn.
⁶ State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. sliu@esf.edu.
⁷ Department of Paper and Bioprocess Engineering, College of Environmental Science and Forestry, State University of New York, Syracuse, NY 13210, USA. sliu@esf.edu.
⁸ State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. xyw@scut.edu.cn.
⁹ State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. chfliu@scut.edu.cn.

Abstract

The maleation of bagasse could greatly increase the compatibility between bagasse and composite matrixes, and the percentage of substitution (PS) of bagasse maleates could be regulated in the homogeneous system. However, due to the complicated components and the linkages of bagasse, it was difficult to control the reaction behaviors of each component. In this paper, the detailed structural changes of bagasse during the homogeneous maleation in ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl) were comparatively investigated with the three main components (cellulose, hemicelluloses, and lignin) from bagasse. The PS of the maleated bagasse was 12.52%, and the PS of the maleated cellulose, hemicelluloses, and lignin were 13.50%, 10.89%, and 14.03%, respectively. Fourier translation infrared (FT-IR) and NMR analyses confirmed that the three main components were all involved in the homogeneous maleation. ¹H-¹³C HSQC analysis indicated that the predominant monoesterification of cellulose, diesterification of hemicelluloses and lignin, and the degradation of the three main components simultaneously occurred. Besides, the quantitative analysis from ¹H-¹³C HSQC revealed the relative PS of reactive sites in each component. ³¹P NMR results showed that the reactivity of lignin aliphatic hydroxyls was higher than that of phenolic ones, and the reactivity of phenolic hydroxyls followed the order of p-hydroxyphenyl hydroxyls > guaiacyl hydroxyls > syringyl hydroxyls.

Keywords: AmimCl; bagasse; maleic anhydride; structural changes.

Abstract

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