Compression of selected glymes in N,N-dimethylformamide + water. The hydration numbers and hydrophobic hydration process of glymes

•The speed of sound of selected glymes in DMF + W mixture was measured at T = (293.15–308.15) K.•The isentropic compressibility coefficient (κS) of glymes solution in a function of molar fraction of water was analyzed.•The changes of the partial molar isentropic compression (KS,m0) of glymes with changing of mixture composition was discussed.•The hydration numbers of glymes in water were calculated and analyzed at four temperatures.