Richard wrote:Does it give the chemical formula for Gelli Baff on the carton? Quite by accident whilst researching a completely different subject I found an entry for Natrosol in Martindale's Extra Pharmacopoeia. It gives Natrosol as hydroxyethylcellulose (which is available in a number of different grades, for example 25, 450, 8000 and 25000, the numbers indicating the average viscosity, in centipoises, of 2% solutions at 20 degrees). Natrosol itself (grade 250) was a trademark of a company called 'Hercules' but that may have changed now as my copy of the book is dated 1972.
You'll find its sodium polyacrylate,( http://en.wikipedia.org/wiki/Sodium_polyacrylate and http://www.chemblink.com/products/9003-04-7.htm) which is similar in properties as polyacrylimide which is what people use for jelly wrestling, ie water saving crystals. Unpolerimised acrylimide is quite toxic but is safe once polymerised but you cant be certain there are no unpolymerised units. The advantage of sodium polyacrylate is that since it will react with salt -(sodium chloride) which is all the dissolving package is. The presence of the sodium ions reduces the water absorbency greatly so no longer the 100-300 times weight down to about 50%. Acrylate is the ion of acrylic acid and it is reacted with sodium hydroxide to create sodium polyacrylate http://depts.washington.edu/chemcrs/bul ... rylate.pdf
Whilst it is non toxic though the second msds sheet has the toxicity note for injection amounts of a rate and skin contact of a rabbit, it can be an irritant and you should be careful not to inhale powder.
http://www.sciencestuff.com/msds/C2688.html
http://www.accepta.com/prod_docs/2032.pdf