Acrylic vs Polyester Yarn: Strength, Warmth, and Which to Choose
Sullivans International
•4 min read
Acrylic and polyester are both synthetic yarns, but they excel in different areas: polyester leads in strength and abrasion resistance; acrylic leads in lightfastness and warmth (about 15% warmer than wool). Which is "better" depends on the performance you need—durability and flatness after washing favor polyester; softness, warmth, and sun resistance favor acrylic.
In this guide, we compare acrylic vs polyester yarn and suggest when to choose each.
Polyester yarn is yarn made from polyester fiber (synthetic polymer). Polyester is strong, abrasion-resistant, elastic, and holds its shape after repeated washing. It is widely used in apparel, home textiles, and industrial applications (e.g. tablecloths, technical fabrics).
Acrylic yarn is yarn made from polyacrylonitrile (acrylic) fiber. Acrylic is often called "synthetic wool": it is bulky, curly, soft, and about 15% warmer than wool. Strength is 22.1–48.5 cN/dtex—1–2.5× wool. Lightfastness is the best among common synthetics; after one year in the sun it is used for curtains, tarps, and awnings. It resists acid, oxidants, and many organic solvents but has poor alkali resistance. Softening temperature is about 190–230°C.
| Property | Polyester | Acrylic |
|---|---|---|
| Strength | Highest among these two; 2.6–8.0 cN/dtex | 22.1–48.5 cN/dtex; 1–2.5× wool |
| Abrasion resistance | Best (after nylon) | Good |
| Elasticity | Close to wool; recovers at 5–6% stretch | Good; ~65% resilience at 20% elongation |
| Warmth | Moderate | ~15% warmer than wool |
| Lightfastness | Good (second to acrylic) | Best among synthetics |
| Shape after washing | Stays flat | Good |
| Price (typical) | Often lower | Often higher |
| Hand | Smooth, flat | Soft, fluffy, wool-like |
Summary: Choose polyester when strength, abrasion resistance, and flatness after washing matter (e.g. table linens, workwear, technical use). Choose acrylic when warmth, softness, lightfastness, and wool-like hand matter (e.g. sweaters, blankets, curtains).
Polyester excels in strength, abrasion resistance, and dimensional stability (stays flat); acrylic excels in lightfastness, warmth, and wool-like softness. There is no single "better"—choose by project: durability and flatness → polyester; warmth, softness, and sun resistance → acrylic.
Polyester is generally stronger (higher cN/dtex) and has better abrasion resistance than acrylic. Acrylic is stronger than wool but not than polyester.
Acrylic has the best lightfastness among common synthetic fibers. Polyester is good but second to acrylic; both are used for curtains and outdoor textiles.
Acrylic raw material and processing (polymerization, spinning, crimping, etc.) often cost more than polyester. Acrylic is priced for wool-like warmth and softness; polyester for strength and versatility.
This article is part of our yarn knowledge series, offering practical insights into synthetic yarn types and selection for knitters and fabric buyers.