New cellulose crystallinity estimation method that differentiates between organized and crystalline phases

Umesh P. Agarwal; Sally Ralph; Richard Reiner; Carlos Baez

doi:10.1016/j.carbpol.2018.03.003

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New cellulose crystallinity estimation method that differentiates between organized and crystalline phases

Formally Refereed

Authors:

Umesh P. Agarwal, Sally Ralph, Richard Reiner, Carlos Baez

Year:

2018

Type:

Scientific Journal

Station:

Forest Products Laboratory

DOI:

https://doi.org/10.1016/j.carbpol.2018.03.003

Source:

Carbohydrate Polymers. 190: 262-270.

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Abstract

A new method is proposed for estimation of cellulose crystallinity (CrI) based on 93 cm⁻¹ Raman band in spectra of cellulose I materials. In this method (93-Raman), CrI was determined based on regression that was developed using the ratios of peak-heights of the 93 and 1096 cm⁻¹ Raman bands (I93/I1096). For calibration purposes, a set of eight samples, all derived from cotton microcrystalline cellulose Whatman CC31 were selected. When the peak intensity ratios (I₉₃/I₁₀₉₆) were plotted against the calculated CrIs of the calibration set samples, the plot showed an excellent linear correlation (R²=0.9888). The 93-Raman method was used to estimate crystallinities of a number of cellulose materials including poplar wood samples that were hydrothermally treated at various temperatures. The wood 93-Raman CrI data showed that the method is able to differentiate between organized and crystalline phases of cellulose, a capability lacking in many other CrI estimation methods.

Keywords

Cellulose crystallinity, Raman spectroscopy, Low frequency, Organized, Crystalline, Hydrothermal, Wood

Citation

Agarwal, Umesh P.; Ralph, Sally A.; Reiner, Richard S.; Baez, Carlos. 2018. New cellulose crystallinity estimation method that differentiates between organized and crystalline phases. Carbohydrate Polymers. 190: 262-270.