In this work, a comparative study of the swelling behavior of poly (1, 7, 7-trimethyl-2-bicyclo [2.2.1] heptanyl) prop-2-enoate) (poly (IBOA)) and its copolymer (poly (IBOA)-co-2-EHA)), prepared by radical polymerization with the addition of a low concentration of crosslinking agent and photoinitiator, was performed. The obtained networks were characterized by FTIR to show the conversion of acrylic band before and after polymerization and by differential scanning calorimetry (DSC).The copolymer network has a single glass transition temperature (Tg) that decreases relative to the poly (IBOA). The swelling study of (poly (IBOAco-2-EHA) was carried out by gravimetric method, in a series of polar (methanol, ethanol, propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol and heptan-1-ol) and non-polar (toluene) isotropic solvents. Solubility, interaction and diffusion parameters that influence the swelling of copolymer in the solvents were calculated. The wellestablished order of swelling (toluene > heptan-1-ol > hexan-1-ol > pentan-1-ol > butan-1-ol > propan-1-ol > ethanol > methanol) in the copolymer was clearly observed and moreover the degree of swelling increased with the presence of EHA in the copolymer. A simple diffusion model was applied (Fick's model) to interpret the swelling data. It was found that the nature of solvent shifts the mechanism from diffusion-controlled in the case of alcohols to non Fickian one for toluene. For a long period, the experimental results were well correlated with the second order diffusion kinetics of Schott.

The present investigation focuses on analysis of swelling behavior of systems composed of linear primary alcohols and photo-chemically crosslinked poly (butyl prop-2-enoate) (PABu).For this purpose, reactive blends composed of monofunctional (n-ABu) and difunctional (1prop-2-enoyloxyhexyl prop-2-enoate) monomers as well as a standard photoinitiator were exposed to ultraviolet-visible (UV-vis) irradiation to induce free radical crosslinking polymerization. Experimental swelling studies of the obtained optically transparent PABu networks in methanol, ethanol, propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol and heptan-1ol were performed by gravimetric sorption measurements. Among the various models available to rationalize the swelling kinetics of these PABu-alcohol systems, the second order approach was found to agree well with the experimental data.In particular it was observed that swelling properties strongly depend on the length of the linear alkyl chain of the primary alcohols. Swelling of PABu network at equilibrium increases from methanol to butan-1-ol where it reaches a maximum and subsequently decreases from butan-1-ol to heptan-1-ol. To understand this unusual behavior, polymer-solvent solubility parameters were considered, which could not account for the swelling maximum detected in the case of butan-1-ol. Molecular simulations performed on model systems composed of a linear primary alcohol molecule set and a reproduced PABu network revealed that their mutual interaction energy times the molar mass of the alcohol show a trend very similar to that of the observed swelling behavior.

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