How much weighs the swelling pressure

We are presenting a new method to study the swelling of gels by following the apparent weight increase during confined swelling. This method, compared to other procedures, is characterized by its simplicity and versatility to study the influence of the experimental conditions such as composition of the swelling agent and temperature. Examples are given for poly(acrylic acid) and poly(N-isopropyl acrylamide) hydrogels and the influence of ethanol content, pH, and temperature in the water pool.