Temperature dependent swelling of different polymer networks was performed in the liquid and gaseous solvent water. To determine the swelling ratio in the water vapour gravimetrically, depending on the change of temperature, a new measure device was developed. Object of this thesis was, to qualify the shape of the swelling curves in the region of the boiling point. Swelling curves were analysed with the results of the statistic theory of swelling additionally. Together with the results of measurements of the same polymer networks in crystalline water, a mathematical description of the swelling curves was performed in solid, liquid and gaseous phase for the first time.