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The page that dripped SLIME!Welcome to the fascinating world of non-Newtonian fluids! These slimes, oozes, globs and the rest all have a high viscosity, which means that they have a resistance to flow dependent on the velocity of flow and a proportionate resistance to shearing forces. If something acts on them with a small amount of force (if you stir them slowly, or let you fingers slowly sink into them) they won't offer as much resistance as they would if a greater force acted on them. If you punch a good stout ooze, it should resist about as much as a brick wall. They fight back. Non-Newtonian fluids are so called because they do not fit into one or another of Newton's laws of how true liquids behave (specifically, in how they react to shearing forces). Quicksand, many pastes and glues, gelatin, and ketchup are all Non-Newtonian fluids. Elmer's SlimeOne of the simplest of the slimes, and a favorite among
schoolteachers. Not terribly toxic, but watch the kiddies so
they don't eat it. It produces a lovely, white (unless you
color it), opaque goo. It will dry out, so store it sealed
and refrigerated. It also has a limited shelf life, and may
eventually develop mold (horrors!) It (usually) cleans up
easily. If it dries on anything, try soaking in water. This is the quick and easy method.Materials
Pour the glue into the jar. Fill the empty glue bottle with water, and add to the jar. Stir. You can add food coloring here if you want to be festive - a few drops will do. Pour one cup (240 ml) of distilled water into the bowl and add 1 teaspoon (5ml) of borax powder. Muddle well. Slowly add the glue mixture to the bowl, stirring as you do so. Place the thick slime that forms into your hand and knead until it feels dry. (There will be an excess of water remaining in the bowl.) It will be wet, stringy and messy at first, but the more you play with it, the better it mixes and the less sticky and firmer it becomes. Store your slime in a zip-lock in the fridge. That's it! Artisan methods: design your slimeThe thing that makes this particular slime work is the bonding of polyvinylacetate (PVAC) molecules by the Borax (sodium tetraborate). The molecules (polymers) are long to begin with, and they are tangled, which is why the glue is so viscous. Once the Borax links up some of the molecules, it becomes even more viscous. Not all of the molecules hook up, though. The more that do, the more viscous it becomes, until it reaches a point where it barely flows at all. The amount of attachment that occurs among the PVAC molecules depends in part on the concentration of Borax solution used. This is where we get the latitude for making different consistencies of slime. All of these variations use the same simple ingredients: a solution of Elmer's glue, and a solution of Borax. The only variations are in the solution concentrations, and in the ratios that the solutions are mixed together. Most basic recipes suggest a 4% Borax (in distilled water) solution for an average slime. This would be app. 1 teaspoon to half a cup (you've got it easy if you use metric!) The glue to water ratio is almost always 1:1, though I have encountered 1:.75. This really won't effect the viscosity, however, the amount of water that the slime retains does effect its "stickiness". The typical glue to Borax solution ratio is 1:1. Ratios of 2:1 and 3:1 are often cited. I have seen them as high as 7:1, but usually the Borax solution was more concentrated. If you want to experiment with making different consistencies of slime, I would suggest two things. First, measure everything metrically, if possible. This makes it much simpler to keep track of concentrations and ratios. Second, start with basic solutions of 50% glue and 4% Borax, mixing them 1:1. Experiment with increasing and decreasing the concentration of Borax solution, all else being the same. The more concentrated the Borax, the more viscous the outcome. You can actually produce something like a hard rubber ball if the concentration is correct. The lower the concentration, and the closer you approach a wet, sticky liquid. Keep notes so you can repeat the results that you like. If you can't quite get the consistency you want, vary the amount amount of water that goes into the mix. PVA SlimeThis is often referred to as "institutional" or "commercial" slime. This is the type that is generally found in toy stores. It is a little trickier to make, not quite as safe, and more difficult to get the main ingredient for (polyvinyl alcohol) than is the Elmer's slime. But it produces a superior slime. Longer lasting, more transparent, and with a visual and tactile appeal that is more, well, "slimy". Assuming you can get hold of PVA, it is a fairly simple process to make slime. First, mix a 4% solution of PVA and water. 4 % would be 40 grams of PVA to 960 ml of distilled water (of course you can adjust and make more or less). Wear a mask and have plenty of ventilation when doing this! It helps to have a heated magnetic laboratory stirrer (don't use one of your good kitchen saucepans - it's best to use pyrex labware). Slowly, gradually, mix the PVA into the distilled water. Heat it slowly, stirring the whole while, until the PVA goes into solution. This will take 15 minutes or more. Do not let it boil. Once cool, the solution can be stored in a stoppered bottle. The 4% Borax solution is made by dissolving a gram of borax into a liter of distilled water. It should go into solution without heating. This can also be stored in a stoppered bottle. Mix the two solutions in a glass or ceramic bowl. Do not use plastic. Start with the PVA solution, and stir in the coloring, if used, and borax solution. The standard ratio is 5 parts PVA solution to 1 part Borax solution. This works well, but ratios have been quoted bother slime makers as 6:1, 20:3, and as high as 200:15 (app. 13:1). The best bet is to start with the basic 4% solutions at 5:1, adjusting the ratio as necessary to get the consistency you want. Store in a sealed container. No need to refrigerate. Keep it clean and it should last indefinitely. I read recently (and I apologize to the author, because I cannot find the page again to reference it) that the consistency of PVA slime depends also on the molecular weight of the PVA used. Some archival art glues are actually a 5% PVA solution. It is almost certainly more expensive to purchase the glue than it would be to purchase the PVA, but, if you do happen to have a bottle around the house that you probably wouldn't use otherwise, it should work (check the ingredients!) Also, some soluble bags used in hospitals are made of PVA. If anyone knows how to make slime from these, I would like to hear about it. Guar gumThis produces a good slime, but is tricky to make, and guar gum must be purchased from a chemical supplier. The guar solution is made by adding a measure of guar gum to distilled water and stirring to dissolve. It will thicken more if you bring it to a simmer for a few minutes. Skim off the scum that forms on top and allow to cool. The Borax solution should be 4% , as with the above slimes. Of all the slime recipes I have collected over the years, none vary so widely in concentrations and proportions as those involving guar gum. Typically, the guar is in 1% to 6% solution (though I have seen it up to 12%), and the ratios of guar to Borax solutions range from 10:1 up to 35:1. Start with a Borax solution of 4%, a guar gum solution of 5% and a mix ratio of 20:1 (guar to Borax). Experiment with the guar solution concentration as well as the ratio that the two concentrations are mixed together until you get the consistency you want. To mix, pour the guar gum solution in a bowl (preferably glass; not plastic), add coloring if you so desire (a few of drops of food coloring works,) and then add the Borax solution. Stir. Guar gum slime improves with age, so let it sit a couple of days for it to be at its peak sliminess. If some happens to get in the carpet, try cleaning with a little vinegar, followed by water. CornstarchCornstarch makes a classic, sticky, messy slime. It is insanely simple to make. There are only 2 ingredients, dry cornstarch and water (food coloring optional). The lines are very thin between dry cornstarch, slime, and cloudy white starch water, so mix slowly and add the water only a little at a time. This stuff will make a mess, no matter how careful you are. Start with 2 parts cornstarch in a bowl (now is the time to add the food coloring). Slowly, add 1 part water, mixing with your hands (there really is no other way) to get all of the powder wet. Have another measure of water handy, and drop in a little at a time, mixing as you go. It will take much less water than you might think to change the consistency much, so add only a few drops at a time. You will know when it is the right amount, as the wet powder will stick together and suddenly start behaving very oddly. This slime has some of the weirdest properties. It will flow fairly quickly into the bottom of the bowl, and your fingers will sink into it readily, but just try and punch it... Electro-active cornstarch slimeMix 3/4 cup (175ml) of cornstarch with 2 cups (475ml) of vegetable oil. Put it into a tumbler in the refrigerator until it is chilled. Remove from the refrigerator, stir to mix (it will have separated), and let warm just enough so that it will flow. Find a block of Styrofoam, about 1by 6 by 6 inches (25x150x150mm - not at all critical), and rub it on your hair (or a wool sweater, or a cat, etc.) to build up a static charge. Tip the container of slime. It should flow slowly. Place the charged Styrofoam just in front of it (an inch or so), in the path of the flow. The slime should stop flowing and seem to solidify. Wiggle the Styrofoam, and the slime will follow it somewhat, and pieces of it may even break off. Remove the Styrofoam, and the flow will resume. Various slimesBaking soda and cornstarchA variation on the cornstarch recipie. Uses 1:1 baking soda to cornstarch instead of just the cornstarch. Supposedly makes a less sticky slime. Laundry starchMix 1 part white glue with 1 part liquid laundry starch. Stir quite a bit, and let rest for 5-10 minutes. Knead the daylights out of it. It will take a while, but it will transform into a very nice ooze. Green jelly oozeThis makes a nice jelly like ooze. First, you need to make some iron acetate. Do this by placing some steel wool in a jar, and adding enough white vinegar to cover it. Let this stand for five days to a week. Pour off some of the mixture into another. In yet another glass receptacle, add equal parts (a tablespoon or so) of this mixture and household ammonia. Use plain ammonia, not sudsy, and not scented. Instant weird green jelly ooze. Note: I haven't gotten this one to work correctly. If you know this slime, and I am leaving something out, please let me know. Play doughNot technically a slime, but it somehow seems to belong here all the same. Non-hardening varietyMix well
In a pan heat 2-tbsp. (10 ml) vegetable oil. Add the other ingredients, and cook 3 minutes. Stir constantly. Let the dough cool. Store in plastic wrap in the refrigerator. Hardening varietyMix well
Add the water gradually, using only enough to produce a workable consistency. To set, bake at 300° F until hard. Slime rules and safety
If you want to know the ingredients to the king of all slimes, Silly Putty, check out http://www.sirds.com/sillyputty/creations/ingredients.html. You won't be able to make it (unless you happen to be a chemist) but it should slake your curiosity.
This page is an extract from an excellent site for scince experiments
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