ON LIQUID WATER ISOTHERMAL SEGREGATION IN A MEDIUM OF HIGHLY ELASTIC HYDROPHOBIC POLYMERS SUCH AS POLYMETHYL METHACRYLATE

Deglassifying the films of plasticized polymethyl methacrylate (PMMA) in heated water causes the spontaneous segregation of water drops of m icrometer and larger radius. This process which is accompanied by a ch ange in the film size is impossible in structureless hydrophobic syste ms. The phenomenon indicates a structural organization of polymer chai ns, which are responsible for adsorption of a certain amount of molecu lar water by hydrophobic PMMA. From a thermodynamic standpoint, ''stru ctural hydrophily'' is of entropic nature and is provided by the micro pore generation caused by fluctuations. The micropores are stabilized through the capture of water molecules. When the polymer transforms to the highly elastic state, zones of a dynamically active microporous s ponge are formed with the participation of moisture. In these zones, t he fluctuation results in the formation and destruction of hydrophobic slits, which ensure the appearance of the water interlayers and drops of critical size that merge into the stable water phase. A thermodyna mic model of the process is considered.