Dear Pallab Das, I don't think that such a conversion exist. It is better to think using the cohesive energy density (CED) which increases with polymer MW, but not as a regular function. This is because when increasing MW other parameters arise and interfer with the ease of solubility, to mention : spatial arrengements and entanglements of chains. These hinder the ease of solvent diffusion. Also you have to consider that when choosing the solvent to low MW polymer by taking the closest solubility parameter value, for sure such a value will be far away for high MW polymer. This means if the solvent is good for low MW, will not be so good for high MW. Example water is a good solvent for PEG's but some PEO's (high MW PEG's) are extremely difficult to solubilize in water. My Regards

Dear Pallab,

I agree with Abdelkader; thermodynamics (entropic term) is the reason...and it is not possible to lump together all monomers-polymers systems, due to different interactions with the sovents

KR Rodion