Cellulose Degradation by Calcium Thiocyanate.

Jeong Jeong,Potthast Potthast,Yang Yang,Kang Kang,Lee Lee

doi:10.3390/polym11091494

Abstract

The dissolution process of cellulose aerogels is an important part of their production. However, if the cellulose is severely degraded during the dissolution process, the quality may be low. To evaluate the degradation of cellulose during the dissolution process using calcium thiocyanate, the hydrolysis and oxidation of cellulose were evaluated by the change in absolute molecular weight and by the changes in the content of carboxyl and carbonyl groups introduced into the cellulose hydroxyl group, respectively. A noteworthy hydrolysis phenomenon was found in the cellulose dissolution process. The rate of hydrolysis increased as the number of hydrates in calcium thiocyanate decreased and as the reaction temperature increased. In the case of the reaction with calcium thiocyanate containing six hydrates, the time to reach a 50% loss of the degree of polymerization of cellulose reduced from 196 to 47 min as the reaction temperature was increased from 100 to 120 °C; however, the effect on oxidation was not significant. The Brunauer–Emmett–Teller (BET) surface area reduced as the degree of cellulose polymerization decreased. Therefore, it is necessary to consider how the cellulose degradation occurring during the cellulosic dissolution process can affect the quality of the final cellulose aerogels.

Highlights

Fossil fuel-based materials replaced many traditional materials during the last century [1].Owing to global warming, recent environmental demands resulted in renewed interest in the use of renewable natural resources as direct sources of biopolymers [2]
Among the various natural polymers, this study focused on cellulose, which is widely used as pulp for making paper, film, and bio-plastic materials
Study, the the dissolution dissolution of of cellulose cellulose fiber, fiber, cotton cotton linter linter (Whatman (Whatman No 1), approximately using calcium thiocyanate resulted in a difference in the number of water molecules approximately 2500 using calcium thiocyanate resulted in a difference in the number of water in calcium in thiocyanate (Figure 1).(Figure

Summary

Introduction

Fossil fuel-based materials replaced many traditional materials during the last century [1].Owing to global warming, recent environmental demands resulted in renewed interest in the use of renewable natural resources as direct sources of biopolymers [2]. Among the various natural polymers, this study focused on cellulose, which is widely used as pulp for making paper, film, and bio-plastic materials. Cellulose is an abundant natural polymer that is polymerized with β-1,4-glycosidic bonds of d-glucose. The degree of polymerization (DP), from under 1000 for chemically pulped fibers to over 10,000 for natural fibers, depends on the type of cellulose resource and the pulping process [3]. Because of these advantages, various studies on topics, such as environmentally friendly cellulose [2]

Methods

Results

Conclusion