Viscosity Enhancers

BuachaillAbroad

Hi peoples,

I am looking to find chemicals which increase viscosity.
The viscosity range I would like is from 10-16 cSt at STP
(Water ~0.9 cSt at STP)

Chemical (or chemical mix) must be:
1) Water soluble
2) Non-hazardous
3) Cheap
4) No effect to Environment, metal, paint, rubber

I've read about using starch, sugar or Polyethylene Oxide.

Note: I may need to mix ethanol-based chemicals with the viscosity enhancer.

Thanks for your help!

BuachaillAbroad

Kevster

I suggest that you contact cosmetic companies, as they will know much more about this than we do. Vicosity Enhancers are used a lot in shampoos, for example. I'm just thinking now actually about PEG (PolyEthylene Glycol) - Wouldn't that increase viscosity? It absorbs water efficiently, is cheap, non-toxic (as far as I know), but I don't know where you can buy it.

sunnyjim

Yeah, I'd go with the ethylene glycol. It's what we use in work for the sub-zero water baths. I've no idea about those viscosity units you're using, but it's cheap enough.

KP81

Buachill,

Starch or cellulose derivatives are good

If you want off the shelf stuff (ie can buy in a supermarket) try corn/potato starch or gelatin. A 50-70%w/w Glycerin-water mixture would give you a 15cP liquid over 0-20degC (http://www.dow.com/glycerine/resources/table18.htm).

If you want to be more scientific use pharma or cosmetic grades of: amylose, hydroxyethly cellulose; hydroxypropyl methyl cellulose; PEG or polyethylene glycol (not the same thing as ethylene glycol BTW, EG is quite toxic) These come in a bewildering array of grades. In general the longer the polymer (higher the molecular weight) the greater the viscosity enhancing effect, provided the polymer remains soluble. Look at the ratio of hydrophobic to hydrophilic groups to get a feel for this.

Your units of centi Stokes measure kinematic viscosity. The more usual unit is dynamic viscosity measured in cP or in SI units the Pa.s (1 cP = 10 mPa.s) (look the difference up on Wikipedia for more info).

How do you plan to measure the viscosity BTW. Viscometers or rheometers are typically used (note these generally measure dynamic viscosity). Also be aware that the viscosity of certain fluids change depending on the applied force (Non-Newtonian flow) and you'd have to use a rheometer for these.

Cheers,

KP

YFlyer

Maybe alginate might do the trick.

http://www.lsbu.ac.uk/water/hyalg.html

mountfoley

Rhidogel (Xanthem gum) is very good for increasing viscosity and is water soluble, etc, hope this is of some help