The Jeffamine ED-600 (supplied by Huntsman) and glycerol monomethacrylate (GMM, supplied by Polysciences) were used as received.
2-hydroxy ethyl acrylate (HEA, supplied by TCI), azo-bis-isobutirenitrile (AIBN, supplied by Glentham) and dioxane (supplied by Panreac) were used as received.
The HCL was prepared as described previously from 3-(acryloyloxy)-2-hydroxypropyl methacrylate and Jeffamine using a catalytic quantity of acetic acid [20 ].
The synthesis of poly-HEA (pHEA) was carried out by thermal polymerization in solution. 665 mg of HEA were introduced into a vial, with a stirrer inside, and dissolved in 10 mL of dioxane. Next, 25 mg of AIBN were added. After that, the solution was left stirring for about 5–10 min for its complete homogenization and then nitrogen was bubbled for 5 min. Finally, the polymerization was allowed to proceed overnight in an oven at 60 °C. The next day, upon cooling to 5 °C separation into two phases was observed, which allows the dioxane to be easily removed.