Cotton consists of the feathery appendages of the seeds in a cotton plant, which assists in dispersing the seed by wind. Cotton fibers would be made out of cellulose.

Wool and fleece are the hair of sheep. Hair is composed of a protein called keratin, which is the same protein that skin, nails, and feathers are made of.

Polyester is synethetic, and I don't know its exact composition, although an ester is the result of a carboxylic acid (-COOH) combined with an alcohol (-OH), creating an ester group.

Fabrics are interesting, aren't they?

You can do experiments to see how water affects fabrics.

1.Look at the fabric labels to see whether they are cotton or polyester or wool or other fibers or 'blends' of different fibers.

2. Then put drops of water on the different fabrics and see how water interacts with them. I put drops of water on my fabrics by sticking my finger into a glass of water and then shaking my finger over the fabric or gently touching the water drop on my finger onto the fabric. Does the water sit on top of the fabric? Does it soak into the fabric?

3. Do you get different results if the fabric is lying on a table or if the fabric is lying over the top of a cup, so that there is air underneath?

4. How fast does the water soak into the different fabrics?

5. Are all your fabrics about the same thickness, or have you tested fabrics that are thin and fabrics that are thick? Do you think there is a difference if the fabric is knit or woven?

I got interesting results with my experiments. One result was really surprising.

Water interacts with materials in different ways.

Some materials 'like' water. They are hydro-philic, and the water will soak into them quickly.

Some materials 'hate' water. They are hydro-phobic, and water will just sit on top of them.

You ask about the absorbent properties of fabrics. The absorbent properties of fabrics are probably different if they are absorbing water or if they are absorbing oil. I'm not going to test the oil-absorbing properties of my fabrics, because then the oil will be hard to wash out. Oil 'hates' water - it is hydro-phobic. We use soaps and detergents to get oil out of fabrics and off of dishes. Soaps and detergents are molecules that have one hydro-philic end and one hydro-phobic end.

You ask about fabrics made of cotton, wool, fleece and polyester. Cotton and wool are natural fibers from cotton plants and sheep. Polyester is a man-made [and woman-made] 'synthetic' fiber made from molecules that can hook together to form long fibers. Fleece is a kind of material that can be made from different fibers - cotton fleece, or polyester fleece, or blends of cotton and polyester, or other fibers or blends of fibers.