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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.
Another slime recipe can be found here as well.
The instructions by themselves are not particularly instructive: "the procedure can be followed from the slime procedure above."
This is mentioned here. There's a bunch of other cool stuff in the same section, too.
The original poster was not saying that making Silly Putty might be a copyright violation. He was saying that the use of Silly Putty -- to wit, to copy (say) your Sunday comics and then stretch them -- was employing a "circumvention device".
The Mongrel Dogs Who Teach
For those of you who are lazy here are a couple of links to buy silly putty in bulk.
From Crayola
Or if you would like to buy 100 pounds of the stuff you can apparently order it directly from Dow Corning. Here's a page with step by step instructions on what to ask for and who to call.
100 Pounds or More
Check out this link for these recipes.
... is whot bwings os tugevza tsuzay.
Mod parent down as ignorant - you'll find it as 20 Mule Team Borax, and it'll be by your washer or under your sink. If you don't have any, go to the detergerent aisle in the grocery store.
from www.sillyputty.com
"Silly Putty is a dilatant compound, a silicone based polymer..." This statement makes sense also because the inventor was (is) a Dow chemist/engineer. Dow has always been a leader in silicone chemistry.
The recipie from U of M is a borate cross-linked PVA (from the Elmer's), better known as slime. This is NOT a silicone polymer.
Before I flame UofM Chemistry dept., I will give them a change to correct this gaff.
sigs are for losers (except to point out that sigs are for losers)
Dow 3179 Dilatent Compound is. It is silicone-based, like the Horta.
You can order 50lb blocks from Crayola or 100lbs from Dow. See http://vern.com/putty/ for more info.
Slashdot editors can't even check facts on Silly Putty stories. Sad.
The latest Slashdot meme.
WRONG!!! Its missing Silicon! It is a fake recipe!
:
Real silly putty does not dry out or leave much of a residue and is of course feshy-colorred.
Real silly putty has alwasy been
65% dimethyl siloxane, hydroxy-terminated polymers with boric acid
-- 17% silica, quartz crystalline
-- 9% thixotrol ST
-- 4% polydimethylsiloxane
-- 1% decamethyl cyclopentasiloxane
-- ~1% glycerine
-- ~1% titanium dioxide
and of course you can manufacture it now, out of patent, but you have to be careful how you market it.
Or you can buy it from DOW in bulk for under 10 dollars per pound.
I am the first post that mentioned this and its 12:18 PM E.S.T. , so I can't imagine how something that I knew most of my adult life was not mentioned or corrected by ANYONE else. More amusing is that no one moderates on slashdot anymore even though technically all email accounts are mostly anonymous.
But for those that care. There is the CORRECT resipe , and its totally different than the poisonous one for mere slime the article mentioned.
The recipe, well, at least the ingredients, are here.
As a followup to my own post, here is the correct Silicon full recipe
:
Preparing "Silly Putty", a silicone polymer (a methyl silicone, polydimethylsiloxane), via the hydrolysis of dichlorodimethylsilane with simple lab tools.
This silicone, which contains residual hydroxyl groups, will be cross-linked using boric acid (B(OH)3). This trifunctional acid forms -Si-O-Blinkages resulting in a peculiar type of gum. The commercial "bouncing putty" found in novelty stores is a silicon polymer with softening agents, fillers and coloring agents added. The actual full list of Silly Putty ingredients with colorants and softening agents is
-- 65% dimethyl siloxane, hydroxy-terminated polymers with boric acid
-- 17% silica, quartz crystalline
-- 9% thixotrol ST
-- 4% polydimethylsiloxane
-- 1% decamethyl cyclopentasiloxane
-- ~1% glycerine
-- ~1% titanium dioxide
This putty recipe is similar and equally pleasing:
Day 1: This reaction must be carried out in a fume hood.
Wear gloves to measure 20 mL of Si(CH3)2Cl (MW = 129.06, density = 1.064 g/mL) in a dry graduated cylinder. Rapidly transfer to a dry 250 mL Erlenmeyer flask equipped with a rubber stopper. Si(CH3)2Cl2 reacts rapidly with moisture to produce HCl gas so make the transfer swiftly. To this add 40 mL of diethylether and hydrolyze by adding 40 mL of H2O dropwise. HCl gas is evolved in this hydrolysis step.
The addition must be made slowly at the beginning of the reaction or too vigorous an evolution of the HCl will occur. The ether component will be warmed up to its boiling temperature if H2O is added too quickly. It is a good idea to have an ice-bath ready to cool down the reaction flask if the hydrolysis becomes too exothermic. The first 10 mL addition of water is very vigorous but less so afterwards. After this initial quantity, you may increase the rate of addition. The product has a very strong odor; be sure to do this in a fumehood!
Separate the ether layer at the completion of the hydrolysis step by pouring the mixture into your 250 mL separatory funnel. Wash the ether layer 3 times with 100 mL (for each wash) of 1 M Na2CO3.
This step is done to neutralize any residual acid remaining in the wet ether solution. Vigorous evolution of CO2 gas is observed at this stage as the neutralization proceeds. Add 10 mL more of diethylether to the flask after the first wash. Finally, perform on additional wash with 100 mL of water. Dry the ether solution over anhydrous magnesium sulfate in a stoppered Erlenmeyer flask, which you let rest for step two.
Day 2:
Decant the ether solution, filtering off any magnesium sulfate, into a pre-weighed 50 mL Erlenmeyer flask and evaporate off the ether using a water bath - not a hot plate. Note the yield of the dimethylsilicone oil (you should have approximately 9.5 g of material).
Add about 5% (by weight) boric acid (about 0.48 g for a yield of 9.5 g of oil), stirring continuously during the addition and for a few minutes after. This will cause the oil to become very viscous.
Heat the mixture to about 170-180 C in an oil bath and leave at this temperature for 2-3 hours. Allow to cool and remove the product from the flask by scraping it out with a spatula. If the gum is somewhat brittle, continued kneading will produce the desired gum-like characteristic. Once the gum has been removed, clean your Erlenmeyer flask with methanol.
Perform and report on the following tests:
(1) When rolled into a ball, does your product give a lively bounce on a hard surface?
(2) Does pulling sharply cause the gum to cleave?
(3) Does pulling slowly result in a stretching reminiscent of chewing gum?
(4) Does your product flow into a flat plate when placed on a flat surface?
(5) Is print transferred to the gum when test (4) is conducted on a flat newspaper?
General References
1. J. E. Mark, H. R. Allcock, R. West, Inorganic Polymers, Prenti
I think this was on /. before, but couldn't find the past story.
I had my students make this one time -- I was teaching a class on polymers. I had seniors in college playing with glue and boarx like little kindergarteners. Hah. They enjoyed it and learned something about viscoelastic polymers in the process, so I think it was all good.
Anyway... while fun, the stuff isn't really Silly Putty (R). That's a silicone polymer. The poly(vinyl alcohol) that's in glues these days does a pretty decent impersonation, though. You'll notice that it does feel and act differently, and it tends to dry out much quicker than the real stuff.
Just in case anyone cared on this obviously slow news day.
I'm suprised that among all slashdotters, nobody mentionned this. I think it's probably Silly Putty (TM) with more intense properties.
my 2 cents
Here we go again!