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Homemade Silly Putty
kinema writes "Have you ever wanted a ball of Silly Putty as big as your head? Now you can make it at home. The University of Minnesota's Chemistry Department has instructions on how to make it on their website." Isn't silly putty a copyright circumvention tool? This should be regulated before it gets out of hand.
You can buy 5 lbs of silly putty for $60. Many people have done this before, and you can do some very interesting stuff with it. Like make a potato gun that shoots baseball sized balls of putty at brick walls. There are videos of this, and the putty ball shatters like a piece of glass because of its "silly" properties.
Its fun to do other experiments like bake it, freeze it, etc...
The Elmber's Glue recipes don't make actual silly putty. They make some cheap nasty knock-off that creates a silly putty-like compound that is slimey, leaves a greasy mess on anything it touches. Not only that, but this putty goes bad over time, unlike the real silly putty, which never dries out or gets moldy.
There is a recipe for making the real silly putty compound, but it is far more difficult and requires ingrediants and tools not found in a grocery store.
You are correct. It is fake!
We made actual silly putty in high school about 20 years ago. The main chemical was highly reactive to water, including the moisture in the air. A small bottle of the stuff (Dimethyldichlorosilane IIRC) came packed in 5 layers of protection, including a small wood box, and could only be ordered with the aid of a helpful adult with access to dangerous chemicals.
When we withdrew the liquid from the bottle using a syringe in our lab's hood, a wet rag 4 feet away starting smoking.
The putty we created wasn't very good. It did bounce, but didn't have all of the properties of the real stuff. Once we realized that we had no good way of disposing of the chemical, we had to keep making putty until it was all gone!
Today, we'd probably all be arrested for doing this in a public high school, but it was a great learning experience.