Dear Noor Ul Ain

The decreasing of swelling process is attributed to the decreasing porosity and this means that swelling ratio and porosity are directly proportional to each other. The addition of inorganic nanoparticles normally play the role of bridges between the polymer chains and then improved stiffness and maintained structural integrity with low porosity and accordingly maintained lower swelling ratio.

Best regards

Hi

Surface morphology and density are the main attributes of porosity.

I feel that we can't say swelling and porosity are directly proportional to each other in all cases.

Noor Ul Ain

If you consider (understand) the coefficients of swelling and porosity as described below, then they, as you can see, are not proportional.

1.swelling coefficient - the ratio of the volume of swollen resin to the volume of dry ground resin> 1

1.coefficient of porosity - the ratio of the pore volume of the resin to the volume of its skeleton< 1

Perhaps you have different ratios. It is necessary to check experimentally the coefficients of porosity and swelling.

Swelling ratio and porosity have reverse proportional to each other. Highest porosity is equal with lowest swelling ratio.

Mohammed Hussein j. H. Al'Atia Thank you so much for your kind response. I have repeated these experiments thrice. I have observed that when i took sample 10 mg of my hydrogel, the swelling ratio and porosity behavior was dissimilar which was upon adding the metal-clay nanoparticles the swelling increased as compared to the control polymer but porosity decreased. however when sample size was increased upto 100 mg the swelling and porosity of the nanocomposite hydrogel was totally different i.e. with the addition of metal nanoparticles the swelling ratio as well as porosity decreased.

Yuri Mirgorod Thanks a lot for your guidance. I have calculated the coefficient of swelling ratio but i did not have knowledge of the coefficient of porosity. I will study about it.