Test method for maturity of cotton fibers - Microscopic method
1 Scope
This document describes a test method for microscopically determining the maturity of cotton fibers expanded with sodium hydroxide solution.
This document is applicable to cotton fibers taken from raw cotton, cotton rolls, cotton slivers, and non-chemically treated yarns
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6097 Sampling method for testing of cotton fibers
GB/T 8170 Rules of rounding off for numerical values & expression and judgement of limiting values
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
mature ratio
ratio of cell wall thickness to standard thickness (0.577)
3.2
dead fiber
fiber whose cell wall thickness is less than or equal to one-fifth of the maximum width after expansion under prescribed conditions
Note: Dead fibers have various forms, usually flat ribbons without twisting or ribbons with more twisting.
3.3
normal fiber
rod-shaped fiber that, after being expanded according to prescribed conditions, presents a discontinuous or almost no trace of a central cavity, and has no obvious curvature
3.4
thin-walled fiber
cotton fiber that does not conform to the characteristics of normal fibers or dead fibers after expansion according to prescribed conditions
3.5
percent maturity
average percentage of mature fibers to total fibers in cotton samples
3.6
immature fiber
cotton fiber that expands according to prescribed conditions and forms a spiral or flat strip, with extremely thin cell walls and almost transparent contours. Its cell wall thickness is less than a quarter of its maximum width
3.7
mature fiber
cotton fiber that, after being expanded according to prescribed conditions, has no curvature and is approximately rod-shaped in shape, with well-developed cell walls. Its cell wall thickness is greater than or equal to a quarter of its maximum width
4 Principles
After cotton fibers were treated with 18% sodium hydroxide solution, the ratio of cell wall thickness to maximum width and fiber morphology were observed one by one with a microscope to determine the maturity of cotton fibers.
Contents
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Principles
5 Reagents
6 Instruments and tools
7 Atmosphere for experiment
8 Sample preparation
9 Test procedures
10 Calculation results
11 Test report
Annex A (Informative) Typical legend of longitudinal microscopy of cotton fibers after expansion with 18% sodium hydroxide solution
Annex B (Normative) Calculation of statistical values and increased test times
Annex C (Informative) Conversion between mature fiber percentage and maturity ratio
Annex D (Informative) Test record sheet for mature fiber percentage and maturity ratio
