Showing papers on "Natural fiber published in 1973"

The Impact of Natural Fiber Science on Manmade Fiber Technology1

Abstract: Analytical methods are described for the chemical characterization of polyamide and polyester fibers. Their origin from natural fiber chemistry is elucidated.End-group data (amino, acylated amino, and carboxyl groups), number-average molecular weights and breaking stress values are given for commercial polyamide fibers produced by several manufacturers. Amino groups were deter mined with 1-fluoro-2,4-dinitrobenzene, using a new technique. Besides its specifity, this chemical method allows the differentiation of primary and secondary amino groups and their determination in the presence of each other. A related topic is the detection of heat damage in polyamides. Heat treatment leads to the formation of basic groups, which can be distinguished spectroscopically from amino groups after reaction with 1-fluoro-2,4-dinitrobenzene. As a practical application the elucidation of the damage of a nylon needle felt, used in a paper machine, is described.Hydrazinolysis was applied for the determination of carboxyl end...