# Does Silly Putty count as a non-Newtonian liquid? **URL:** \ **Category:** Factual Questions\ **Created:** [December 23, 2012, 1:54pm UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918 "2012-12-23T13:54:44Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Jonathan\_Chance](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jonathan_chance/32/701_2.png) [@Jonathan\_Chance](https://boards.straightdope.com/u/Jonathan_Chance)\ **Post date:** [December 23, 2012, 1:54pm UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/1 "2012-12-23T13:54:44Z")
My 12-year-old wants to know. She got the idea by how a snowman, made with a silly putty knock off, melted overnight. Then I told her about how it shatters if dropped from a height. Then she said to ask you guys. ---
**Author:** ![Norse](https://avatars.discourse-cdn.com/v4/letter/n/a9adbd/32.png) [@Norse](https://boards.straightdope.com/u/Norse)\ **Post date:** [December 23, 2012, 1:58pm UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/2 "2012-12-23T13:58:31Z")
Being a viscoelastic liquid, it’s definitely non-Newtonian. Remember, a Newtonian liquid is purely viscous, not viscoelastic, and to top it up the viscosity must be constant both with time and shear rate. ---
**Author:** ![Norse](https://avatars.discourse-cdn.com/v4/letter/n/a9adbd/32.png) [@Norse](https://boards.straightdope.com/u/Norse)\ **Post date:** [December 23, 2012, 2:11pm UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/3 "2012-12-23T14:11:07Z")
(Too late for the edit window) In ascending levels of complex behavior of solids/fluids, you’ll have: [ul] [li][Newtonian fluid](http://en.wikipedia.org/wiki/Newtonian_liquid): No elastic properties, viscosity independent of shear rate and time. Examples: Sugar syrup, water. Also [Hookean solid](http://en.wikipedia.org/wiki/Hooke's_law): Spring rate independent on strain or strain rate[/li][li][Non-Newtonian fluid](http://en.wikipedia.org/wiki/Non-Newtonian_fluid): No elastic properties, viscosity varies with e.g. shear rate or time. Examples: Latex paint (thixotropic, e.g. viscosity decreases with time at constant shear rate), corn starch suspensions (dilatant, e.g. viscosity increases with shear rate)[/li][li][Viscoelastic](http://en.wikipedia.org/wiki/Viscoelasticity) material: Both elastic and viscous behavior, which phenomenon that dominates is usually determined by shear rate. Examples: Silly putty or polyetyhlene plastic bags[/li][/ul] IMO, the behavior of silly putty can be almost perfectly described by the [Maxwell model](http://en.wikipedia.org/wiki/Viscoelasticity#Maxwell_model) ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [December 23, 2012, 2:19pm UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/4 "2012-12-23T14:19:59Z")
Are [oobleck and silly putty](https://en.wikipedia.org/wiki/Non-newtonian_fluid#Examples) both pretty much the same type of non-Newtonian fluid? They both fall into the viscoelastic category. Can they both be well-described using the Maxwell model? ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [December 23, 2012, 3:08pm UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/5 "2012-12-23T15:08:03Z")
My understanding is that oobleck is as it changes viscosity under pressure. I don’t believe silly putty is, but could be wrong. ETA: I looked at the link and was surprised to see silly putty on it! Perhaps I’m wrong… ---
**Author:** ![Norse](https://avatars.discourse-cdn.com/v4/letter/n/a9adbd/32.png) [@Norse](https://boards.straightdope.com/u/Norse)\ **Post date:** [December 24, 2012, 12:52am UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/6 "2012-12-24T00:52:28Z")
> [@ZenBeam](#): > > Are [oobleck and silly putty](https://en.wikipedia.org/wiki/Non-newtonian_fluid#Examples) both pretty much the same type of non-Newtonian fluid? No. > [@ZenBeam](#): > > They both fall into the viscoelastic category They don’t. In my [post #2](http://boards.straightdope.com/sdmb/showpost.php?p=15826124&postcount=3) I already mentioned starch suspensions. They are basically strongly shear-thickening _viscous_ fluids and can’t be modeled by the Maxwell model. Silly putty, however, is a near-perfect example of a _viscoelastic_ Maxwell fluid ---
**Author:** ![Jonathan\_Chance](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jonathan_chance/32/701_2.png) [@Jonathan\_Chance](https://boards.straightdope.com/u/Jonathan_Chance)\ **Post date:** [December 25, 2012, 2:35am UTC](https://boards.straightdope.com/t/does-silly-putty-count-as-a-non-newtonian-liquid/644918/7 "2012-12-25T02:35:24Z")
You people are excellent. Truly.