Chemical composition of some common fibers
| Type of fiber | Cellulose | Lignin | Pentosan | Ash |
|---|---|---|---|---|
| Seed flax | 43-47 | 21-23 | 24-26 | 5 |
| Kenaf (Bast) | 44-57 | 15-19 | 22-23 | 2-5 |
| Jute (Bast) | 45-63 | 21-26 | 18-21 | 0.5-2 |
| Hemp | 57-77 | 9-13 | 14-17 | 0.8 |
| Ramie | 87-91 | - | 5-8 | - |
| Kenaf (Core) | 37-49 | 15-21 | 18-24 | 0.8 |
| Jute (Core) | 41-48 | 21-24 | 18-22 | - |
| Abaca | 56-63 | 7-9 | 15-17 | 1-3 |
| Sisal | 43-62 | 7-9 | 21-24 | 0.6-1 |
| Cotton | 85-96 | 0.7-1.6 | 1-3 | 0.8-2 |
Diameter of Natural and Meltblown Fibers
| Material | Diameter Mean Value (microns) | Coeff Variation(%) |
|---|---|---|
| Spider silk | 3.57 | 14.8 |
| B. mori Silk | 12.90 | 24.8 |
| Merino Wool | 25.50 | 25.6 |
| Polyester | 13.30 | 2.4 |
| Nylon 6 Filament | 16.20 | 3.1 |
| Kevlar 29 | 13.80 | 6.1 |
Effects of Acids on Common Fibers - Comparison
| Fiber | Effects of Acids |
|---|---|
| Acrylic | Resistant to most acids |
| Modacrylic | Resistant to most acids |
| Polyester | Resistant to most mineral acids disintegrated by 96% sulhric |
| Rayon | Disintegrates in hot dilute and cold concentrated acids |
| Acetate | Soluble in acetic acid, decomposed by strong acids |
| Triacetate | Similar to acetate |
| Nylon 66 | Decomposed by strong mineral acids, resistant to weak acids |
| Olefin | Very resistant |
| Glass | Resists most acids. Etched by hydrofluoric acid and hot phosphoric acid |
| Cotton | Similar to rayon |
| Wool | Destroyed by hot sulfuric, otherwise unaffected by acids |
Effects of Alkalies on Common Fibers - Comparison
| Fiber | Effects of Alkalies |
|---|---|
| Acrylic | Destroyed by strong alkalies at a boil, resists weak alkalies |
| Modacrylic | Resistant to alkalies |
| Polyester | Resistant to cold alkalies, slowly decomposed at a boil by strong alkalies |
| Rayon | No effect by cold, weak alkalies, swells and loses strength in concentrated alkalies |
| Acetate | Saponified, little effect from cold weak alkalies |
| Triacetate | Not effected up to pH 9.8,205' F; better than acetate |
| Nylon 66 | Little or no effect |
| Olefin | Very resistant |
| Glass | Attacked by hot weak alkalies and concentrated alkalies |
| Cotton | Swells when treated with caustic soda but is not damaged |
| Wool | Attacked by weak alkalies, destroyed by strong alkalies |
Effects of Organic Solvents on Common Fibers - Comparison
| Fiber | Effects of Organic Solvents |
|---|---|
| Acrylic | Unaffected |
| Modacrylic | Soluble in warm acetone, otherwise unaffected |
| Polyester | Soluble in some phenolic compounds, otherwise unaffected |
| Rayon | Unaffected |
| Acetate | Soluble in acetone, dissolved or swollen by many others |
| Triacetate | Soluble in acetone, chloroform and swollen by others |
| Nylon 66 | Generally unaffected, soluble in some phenolic compounds |
| Olefin | Soluble in chlorinated hydrocarbons above 160' |
| Glass | Unaffected |
| Cotton | Resistant |
| Wool | Generally resistant |
Effects of Sunlight on Common Fibers - Comparison
| Fiber | Effects of Sunlight |
|---|---|
| Acrylic | Little or no effect |
| Modacrylic | Highly resistant, some loss of strength and discoloration after constant exposure |
| Polyester | Some loss of strength, no discoloration, very resistant behind glass |
| Rayon | Generally resistant, loses strength after long exposure |
| Acetate | Approximately same as rayon |
| Triacetate | Resistant, loses strength after long exposure |
| Nylon 66 | No discoloration, strength loss after long exposure |
| Olefin | Very resistant, retains 95% strength after 6 months exposure |
| Glass | None |
| Cotton | Strength loss on long exposure |
| Wool | Strength loss, dyeing is affected |
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