Degumming of ramie: the role of the individual constituents of the gummy material

The stepwise removal of the components of gummy material found on ramie fibres was used to determine the effects of the individual constituents on the whiteness and yellowness indices of the fibres. The main components were found to be hemicellulose, pectin and lignin and these had the greatest effect on the whiteness and yellowness indices. A spectroscopic method for assessing the hemicellulose and pectin content of the degumming bath was investigated and found to be comparable to the results of chemical analysis. The spectroscopic method was used to study the removal of hemicellulose and pectin continuously during degumming, and the data obtained were used to calculate rate constants for the degumming process.