It depends. If I say cotton, it is the natural fibre on the other hand we called polyester is man made or synthetic fiber. The fibre of cottons are short & staple fibre, in polyester you can get your expected form. That’s why polyester strength are better than cotton. Here I can give some properties of cotton & polyester that can makes you better to know about the comparison:

Cotton :

Cellulose Fibre collect from cotton bale.

Soft & Comfort to wear.

It can resists static electricity.

Wrinkles easily

absorb water more than polyester.

Polyester :

Synthetic Fibre chemically made.

Polyester fibres are really strong

Very durable & long resistance

Quick drying

You can was easily.

Also wrinkle resistance.