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An investigation of the structural characteristics of modified cellulose from acacia pulp

In this paper, the structural characteristics of the modified celluloses from acacia pulp in Vietnam were investigated and compared to other pulps. The total crystalline index (TCI), the lateral order index (LOI) and the hydrogen bond intensity (HBI) were evaluated by the FTIR spectra. The size of crystallites was considered by XRD patterns. | Vietnam Journal of Science and Technology 55 (4) (2017) 452-460 DOI: 10.15625/2525-2518/55/4/9216 AN INVESTIGATION OF THE STRUCTURAL CHARACTERISTICS OF MODIFIED CELLULOSE FROM ACACIA PULP Doan Minh Khai1, *, Phan Duc Nhan1, Trinh Dac Hoanh2 1 2 Military Technical Academy, 236-Hoang Quoc Viet, Cau Giay, Hanoi Institute of Military Science and Technology, 17 Hoang Sam, Cau Giay, Hanoi * Email: khaihv@gmail.com Received: 10 February 2017; Accepted for publication: 22 June 2017 ABSTRACT In this paper, the structural characteristics of the modified celluloses from acacia pulp in Vietnam were investigated and compared to other pulps. The total crystalline index (TCI), the lateral order index (LOI) and the hydrogen bond intensity (HBI) were evaluated by the FTIR spectra. The size of crystallites was considered by XRD patterns. Peak separations were carried out using Gaussian deconvolution for the band at 3700 - 3000 cm-1 of the FTIR spectra and the XRD spectra. The results show that the TCI, LOI and HBI of modified acacia cellulose I are found to be around 1.09, 2.22 and 2.33, respectively, and the TCI, LOI, HBI of acacia cellulose II are found to be around 1.09, 1.51, 2.06, respectively. The crystalline size of modified acacia cellulose I is found to be as follows L(101) ~ 4.33 nm, L(101) ~ 8.58 nm and L(002) ~ 4.80 nm, and that of cellulose II is found to be as follows: L(101) ~ 4.04 nm, L (101) ~ 3.55 nm and L(002) ~ 2.99 nm. Keywords: structural characteristics, modified cellulose, acacia pulp. 1. INTRODUCTION Cellulose, a natural polymer, is applied for making paper and preparing a lot of derivatives (such as nitrocellulose, methyl cellulose, cellulose acetate and etc.) [1]. In order to prepare the derivatives, cellulose is often purified and modified to increase its purity and reactivity. In making paper, pulps are cooked and bleached with brightness up to 89 %ISO. These pulps only have a content of alpha-cellulose of round 90 % weight and a content of lignin .