Improving Viscosity of Cashewnut Shell Liquid(CSNL)

Remove the more volatile components in the oil; pass it through an evaporator and pull a vacuum on it, perhaps?

Agreed the small difference in viscosity could be based on air entraped during processing. A quick check on the specific gravity could determine if air is entrapped into the oil. Even a small amount of nucleation would quickly lower the viscosity. Nucleation is a tactic used in the processing of polyols to lower their viscosity to improve mix with isocyanates.

I agree with the first poster, but I would also suggest that you obtain a sample of the supposed "standard sample" for comparative analysis and if it does meet the test criteria, I would have FTIR analysis to determine the differences in the oils .

I've just got to know, just exactly what does one do with Cashewnut Shell Liquid????

I have No idea either I know what to do with cashew nuts though YUM

Did your CSNL ever meet the viscosity requirements? As a natural product, you must expect some variation with respect to source, seasonality, and processing changes. What is your application? If the product is unsaturated, "blowing" with air could cause some dimer formation and a subsequent increase in viscosity. Color changes are to be expected also.

The viscosity required is between 200-250 cps , Brookfield @25C and 20 rpm. the viscosity we get is between 125 to 195 cps based on the results of a few sample tests.

The CNSL is used for brake lining industry and other engineered particle industries laminated products, rubber compounding etc.

If you blow air will it cause any oxidation that will change the chemistry of the product?

Thank you very much for the feedback

If you are trying to replace an existing oil with the CNSL and the application depends on being reactive, i.e. based on the chemistry of the materials, then "blowing" will change the physical properties, but will also change the reactive properties. If the application requires "air-drying" through reaction with oxygen in the air and the unsaturation level is just what is required, then I suggest a mechanical way of increasing the viscosity of the product. Mechanically easiest to fab and run is a gas-stripper using an inert gas to remove the most volatile compounds. This could be your control to compensate for seasonal or source variations too.

Thank you very much for your advice. I suppose I can try to use nitrogen to flush out the volatiles.