Science Buddies: "Ask an Expert"

When I was in 6th grade, during a in class science fair. A fellow student did something, that to this day, I have yet to figure out. I would like to show my children as well, to get them more intrested in science. Please help. Here is what happened. The student poured 2 unlabled liquids into a standard home bucket. The two liquids one of which i do not remember very well, but he other, seamed to look like chocolate syurp, or dirty motpr oil, and about as thick as them as well. After pouring the two liquids into the bucket, he then stirred them, with two wooden rulers, rubber banded together. The result of doing this, amazed everyong in the classroom. What happened was, the bucket fill with a rootbeer brown color substance, that very soon became firm, yet solid to a point, and look much like insulating foam, used in todays homes. Keep in mind I saw this back in 1973. Any help to point me into the right direction, would be great, Thanks.

Hi,

Your description sounds to me like a formation of a polyurethane foam, though it is not certain to me that it was. Here is a resource describing a number of plastic synthesis demonstrations. Use it with extreme caution, as a lot of the reactants are toxic, and must be handled with extraordinarily good ventilation and avoidance of skin contact to avoid toxicity to(i.e. poisoning of ) experimenter and bystanders. Be extremely careful!!!!!

http://www.chymist.com/Polymers.pdf

Hope this helps!

Best regards,

Barrett Tomlinson