1. BURN TESTS
Procedure: Cut a small sample of textile fiber and holding it in a
tweezer or forceps cautiously ignite with a matchstick or lighter. Observe
the sample carefully, because each fiber type will burn in a specific way,
producing different colored smake, a particular smell and leaving its own
kind of residue. To match your findings with the correct fiber compare with
the chart below.
FIBER |
Performance
at flame |
Odor |
Residue |
| |
Approach
to flame |
In the
flame |
Withdrawn
from flame |
|
|
SILK |
Shrinks
away |
Burns
slowly |
Self
extinguishing |
Burning
hair |
Brittle, swollen,
black ash |
WOOL |
Shrinks
away |
Burns
slowly |
Self
extinguishing |
Burning
hair |
Brittle, swollen,
black ash |
COTTON |
No
effect |
Burns
readily |
Continues
to burn |
Burning
paper |
Gray
skeletal ash |
NYLON |
Shrinks
away |
Burns slowly
and melts |
Often self
extinguishing |
Celery
Sometimes
perceptible |
Hard light
colored bead |
ACRYLIC |
Shrinks
away |
Burns slowly
and melts |
Continues to
burn
and melt |
Acrid |
Brittle black
bead |
POLYPROPYLENE
(OLEFIN) |
Shrinks
quickly |
Burns
and melts |
Burns
and melt |
Not defined
|
Hard, round
bead, maybe
light brown |
2. SOLUBILITY OF FIBERS
Some procedures may involve heat, and some some solvents are toxic and corrosive
and flammable. Use extreme caution !
| |
Acetone 100% |
Hydrochloric acid 20% |
Sulfuric acid 60% |
Sulfuric acid 70% |
Chlorine bleach 5% |
Formic acid 90% |
ACETATE |
Soluble |
Insoluble |
Soluble |
Soluble |
Insoluble |
Soluble |
ACRYLIC |
Insoluble |
Insoluble |
Insoluble |
Insoluble
depending on type |
Insoluble |
Insoluble |
COTTON |
Insoluble |
Insoluble |
Slightly soluble |
Soluble |
Insoluble |
Insoluble |
HAIR |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Soluble |
Insoluble |
HEMP |
Insoluble |
Insoluble |
Slightly soluble |
Soluble |
Insoluble |
Insoluble |
LINEN |
Insoluble |
Insoluble |
Slightly soluble |
Soluble |
Insoluble |
Insoluble |
MODARYLIC |
Soluble or Insoluble
depending on type |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
NYLON |
Insoluble |
Soluble |
Soluble |
Soluble |
Insoluble |
Soluble |
OLEFIN |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
POLYESTER |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
RAMIE |
Insoluble |
Insoluble |
Slightly soluble |
Soluble |
Insoluble |
Insoluble |
RAYON |
Insoluble |
Insoluble |
Soluble |
Soluble |
Insoluble |
Insoluble |
SILK |
Insoluble |
Partially Soluble |
Soluble |
Soluble |
Soluble |
Partially soluble |
Wool |
Insoluble |
Insoluble |
Insoluble |
Insoluble |
Soluble |
Insoluble |
ADDITIONAL SOLUBILITIES
- Polypropylene (olefin) soluble in m-xylene
and cyclohexanone.
- Acrylic soluble in dimethyl formamide.
- Polyester soluble in m-cresol.
- Nylon 6 is soluble in dimethyl formamide and nylon 66 is not.
3. PHYSICAL PROPERTIES OF FIBERS
Natural Fibers |
Density
g/cc |
Melting Point
Degree C (Degree F) |
CELLULOSE |
1.51 |
None |
SILK |
1.32-1.34 |
None |
WOOL & OTHER HAIR |
1.15-1.30 |
None |
Man-Made Fibers |
|
|
ACETATE, secondary |
1.32 |
260 (500) |
ACETATE, tri. |
1.30 |
288 (550.4) |
ACRYLIC |
1.12-1.19 |
None |
MODACRYLIC |
1.30 or 1.36 |
188(370.4 not sharp) or 120(248) |
NYLON 6 |
1.12-1.15 |
213-225(415.4-437) |
NYLON 66 |
1.12-1.15 |
256-265(492.8-509) |
POLYESTER |
1.38 or 1.23 |
250-260(482-500) or 282(539.6 ) |
POLYPROPYLENE |
0.90-0.92 |
170(338) |
RAYON |
1.51 |
None |
