Is acrylic as warm as wool?

When dry, acrylic is lofty and quite warm. But wool insulates even when wet and breathes far better, so wool stays comfortable across more conditions. Acrylic can feel clammy once it is damp or you start to sweat.

Why does acrylic pill so much?

Acrylic fibers are smooth and not very elastic, so loose fiber ends work to the surface and tangle into pills, and because the fiber is strong those pills cling rather than wearing away. Wool pills too but its scales and crimp help it resist and shed pills better.

Is acrylic just fake wool?

Essentially. Acrylic was developed to mimic wool's softness and warmth in a cheap, washable, moth-proof synthetic. It captures the look and much of the loft, but not wool's breathability, odor resistance, or wet-warmth.

Side by side

Wool vs Acrylic

Wool and acrylic are the natural and synthetic versions of the same idea: a soft, warm, lofty fiber for sweaters and blankets. Wool is the crimped fleece of the sheep, warm even when damp, naturally resilient, and breathable. Acrylic is a petroleum-based synthetic made to imitate it, cheaper, machine-washable, and moth-proof, but less breathable, prone to pilling, and quick to feel clammy or hold odor.

Wool

No. 127

the fleece fiber, woven or knitted · first documented Antiquity

Acrylic

No. 123

knitted from polyacrylonitrile staple · first documented 1950

The differences

Aspect	Wool	Acrylic
Origin	Natural: the crimped fleece of the sheep.	Synthetic: spun from polyacrylonitrile (petroleum).
Warmth	Very warm, and insulates even when wet.	Warm and lofty when dry, but loses warmth when wet.
Breathability	Breathable; absorbs moisture and resists odor.	Low breathability; can feel clammy and hold odor.
Care and durability	Often needs gentle washing; can shrink and felt; moths eat it.	Machine-washable, moth-proof, but pills readily and can wear shiny.
Cost	More expensive.	Cheap.

Which to choose

Choose wool for warmth that survives damp, breathability, and resilience, accepting the cost and the care. Choose acrylic for a cheap, washable, moth-proof knit, accepting that it breathes less, pills more, and does not regulate temperature like wool. Blends aim for wool's comfort at acrylic's price.

Common questions

Is acrylic as warm as wool?: When dry, acrylic is lofty and quite warm. But wool insulates even when wet and breathes far better, so wool stays comfortable across more conditions. Acrylic can feel clammy once it is damp or you start to sweat.
Why does acrylic pill so much?: Acrylic fibers are smooth and not very elastic, so loose fiber ends work to the surface and tangle into pills, and because the fiber is strong those pills cling rather than wearing away. Wool pills too but its scales and crimp help it resist and shed pills better.
Is acrylic just fake wool?: Essentially. Acrylic was developed to mimic wool's softness and warmth in a cheap, washable, moth-proof synthetic. It captures the look and much of the loft, but not wool's breathability, odor resistance, or wet-warmth.

Full entry: Wool Full entry: Acrylic

Sources & References

1.Wool, Wikipedia
2.Woolen, Wikipedia
3.Acrylic fiber, Wikipedia
4.Polyacrylonitrile, Wikipedia