High pressure induced coil-globule transitions of smart polymers

摘要: In current work time-resolved optical spectroscopy (TROS) has been used to study coil-globule transitions monitored by the local segmental dynamics of anthracene labeled poly (N-isopropymethacrylamide), PNIPMAM as a function pressure (0.1 MPa-200 MPa) over temperature range 283 K 333 K. The positions temperature-induced transition were observed be independent on molecular weight polymer at low pressures. pressure-induced dependent temperatures below LCST atmospheric pressure. Double globule-coil-globule was occur with increasing nearly above LCST. All these results along values intrinsic viscosity evaluated from correlation times measured for globules formed different pressure/temperature conditions suggest mechanisms compactisation governed and and, correspondently, types final structures. At pressures compact, well-packed are forming via initial interactions between neighboring parts chain further collapse. Relatively loosened particles pressurizing temperatures. Interaction remote units takes part first stage globule formation. And finally, rather solvated irregularly twisted high temperatures, i.e. conditions, when both processes involved.