# Additive for water to increase the viscosity to a value between 5 and 20 cP [closed]

Is there an additive that I can add to water that will increase the viscosity to a value between $$5$$ and $$\pu{20 cP}$$? Ideally, I would like the mixture to be newtonian and since I will be working with gallons of mixture, it would be nice if I didn't have to add too much of the stuff.

• 5 to 20 cP is a lot! I don't think simple addition of organic solvents can achieve that. What is the purpose? Polyols like glycerin are water miscible and they might be Netwonian. – M. Farooq Aug 12 '20 at 3:10
• Do you have some own ideas about this? If you work with gallons of liquids, you must have some experience. (Btw. 1 cP = 1 mPas = pure water) – Karl Aug 12 '20 at 8:01
• Without providing the purpose and acceptable additivce properties, the question is very unclear. – Poutnik Aug 12 '20 at 17:10

You wasn't clear about your purpose to increase viscosity of water (water has viscosity of $$\pu{1 mPa\cdot s}$$ or $$\pu{1 cP}$$). However, whatever your reason, xanthan gum would be the materiel you are looking for. Kyoto Electronics has published a note on measurement of viscosity of xanthan gum solution. According to their results (average of 5 tests), 0.1% xanthan gum solution has shown viscosity of $$\pu{19.1 cP}$$. Five sample averages of 0.2% and 0.3% solutions have given viscosity readings of $$\pu{57.54 cP}$$ and $$\pu{134.6 cP}$$.
Accordingly, you can use range of percentages (0.01-0.1%)of xanthan gum to get water viscosity of $$\pu{5-20 cP}$$. The amount of material to add to water is minimal as you wanted. In addition, Casson plot (shear rate versus shear stress) of 0.1% xanthan gum solution is a straight line. Hence this solution is believed to be a Newtonian solution.
• @M. Farooq: Each solution (0.1%, 0.2%. and 0.3%) has a constant shear rate ($52.81, 22.87$, and $\pu{10.69 s-1}$). Do they Newtonian? – Mathew Mahindaratne Aug 12 '20 at 6:19