A DSC-study on the demixing of binary polymer solutions
نویسندگان
چکیده
Concentrated polymer solutions showing an Upper Critical Solution Temperature behavior are studied with respect to liquid-liquid demixing after a temperature quench. Models proposed in literature are compared and critically evaluated. These models describe the kinetics of liquid-liquid demixing accurately only in a limited region of quench depths. Growth of liquid-liquid demixed domains shows a growth rate of the cell diameter following a power law with an exponent of 1/3 only in a limited region. Quench depths close to the binodal and close to the glass transition temperature show much lower growth rate exponents. The time scales of theoretical descriptions on the formation of demixed domains differ orders of magnitudes with experimental growth rate data. A model is proposed to relate the knowledge of isothermal experiments to non-isothermal experiments and it appears that besides the influence of the quench depth more physical phenomena play a role, like the hydrodynamic flow stage and viscoelasticity.
منابع مشابه
comparison between to versions of the SAFT EOS in the study of PVT and VLE phase behavior of pure polymer melts and binary polymer solutions
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