Are there different types of super-absorbent polymers?
There are about 800 to 1000 different recipes for these polymers – but they are divided into two big categories: polyarcylamide and polyacrylate. Polyacrylate (called in the industry PAC) are used in disposable diapers, sanitary napkins, etc. and are capable of holding a huge amount of water – between 600 and 800 times its weight (purity of the water determines this range – the more dissolved solids in the water, the less liquid the polymers can hold). Polyacrylates are usually made with sodium and are more environmentally friendly, breaking down first into ammonia salts and then nitrogen and CO2 in about 4 to 6 months. They are often sold with an environmentally friendly green label and retail for around $10 to $12 per pound. In contrast, polyacrylamides (often known as PAM) absorb only about 300 – 400 times its own weight in water, use a variety of potassium molecules for cross-linking, and take between 5 and 7 years to completely breakdown. Because of the lower absorbency and longer
