Research on the character and degumming process of different parts of ramie fiber

The aim of this paper is to study the differences of the aggregation structure, physical properties and chemical composition of different parts of ramie fiber, as well as segmented degumming processes applying to those different parts. The ramie was divided into three parts, namely the root, the middle and the head and then the traditional two-step alkali method was adopted for degumming. It has been observed that the linear density and breaking strength reduced gradually from the root to head and the friction coefficient of the head was the largest. X-ray diffraction measurement found that the crystallinity of the middle fiber was the highest. Fourier transform infrared spectroscopy revealed that the component content of different parts was not the same and there was much more gum content on the head, which was also confirmed by scanning electron microscopy. To shorten the degumming process and reduce the energy consumption that the two-step segmented degumming caused, the one-step optimization process was explored. The results illustrated that by using one-step optimization segmented degumming, the residual gum content of the head, the middle and the root were 2.55%, 2.17% and 2.12%, respectively. By using two-step degumming, the residual gum contents were 2.16%, 1.97% and 2.07%, respectively. Contrasting one-step degumming and two-step degumming, it could be concluded that the head and the middle parts were suitable for two-step degumming while the root part was suitable for one-step degumming.