Nylon

Polypropylene
(Olefin)

Polyester (PET)

Wool

PTT (Corterra^®, Triextra^®, Sorona^®, SmartStrand^®)

Market

~50%

~15%

~29%

~2%

~4% and rising

“Hand” (Softness)

Good

Poor

Very Good

Excellent

Excellent

I.D.
Method

Dissolves in formic acid. Burns to a hard black bead; puffs white smoke; extinguishes

Floats in water. Burns to a round hard tan bead.

Dissolves in hot meta-cresol. Burn test: Orange sputtering flame and a black sooty smoke.

Dissolves in chlorine bleach. Burns with a burned-hair odor to a black crumbly residue.

Burn test: Orange sputtering flame and a black sooty smoke.

Moisture Absorption

4.2-4.5%

0.01%

0.04-0.08%

Up to 30%

0.04-0.08%

Specific Gravity

1.14

0.90

1.23

1.32

1.35

Resilience

Excellent

None

Fair

Good

Good

Abrasion Resistance

Excellent

Very Good

Good

Good

Very Good

Effects of Acids, Alkalis, and Solvents

Resistant to weak acids, but decomposes in strong mineral acids

Chemically inert

Resistant to most acids and solvents

Sensitive to acids and alkalis

Resistant to most acids and solvents

Dye Methods

Acid; some solution dyed

Solution dyed

Dispersed Dyes

Various

Dispersed Dyes, Solution Dyed

Resistance to Mildew, Aging, Sunlight

Excellent resistance to mildew and aging. Prolonged sunlight can cause degradation.

Good resistance to all three

Excellent resistance to mildew and aging. Prolonged sunlight can cause degradation

Damaged by sunlight, mildew, moths, beetles. Sunlight can cause yellowing.

Good

Color Retention

Very good

Excellent

Good

Good

Good

Stain Resistance

Poor (5th generation very good)

Excellent

Excellent

Very Poor

Excellent

Stains/Soils Attracted to Fiber

Acid dyes, except for 5th generation

Oil based

Oil based

Protein, urine, blood, meat juices

Oil based

Melt Point °F

Type6-435º F; Type6,6-490º

320º F

509º F

None (ignites)

440º F

Cigarette Burn Resistance

None

None

None

Very good

None