On thermal analysis of hybrid polymer systems
Industrial Chemistry Research Institute (ICRI), Rydygiera 8, Warszawa 01-793, Poland
Recently, hybrid polymer systems have attracted a great deal of attention as materials that combine different features of their components with a synergistic improvement of their properties. Thermal properties of such systems are often needed for many applications, and the differential scanning calorimetry (DSC) and thermogravimetry (TG) methods are used for this purpose. Literature data revealed that characteristic temperatures (such as glass transition, melting, and decomposition temperatures) and mass residues, as well as activation energies of decomposition, are usually determined. The TG and DSC methods were also applied for investigations of the polysiloxane-polytetrafluoroethylene (SIL-PTFE) hybrid system of a semi-IPN nature. Perkin Elmer DSC-7 and TGA-7 instruments were used. The thermal stability of tested materials has been compared using 1/Tdi vs the heating rate plots (Tdi is the temperature of initial mass loss). The activation energies of decomposition (Ead) have also been determined using the Kissinger (KI) and Ozawa (OZ) methods, respectively. Both methods are found to be consistent, since the Ead(KI) value is represented by one point on the plot of Ead(OZ) vs conversion degree. For the SIL-PTFE system it has been found that the thermal stability of SIL-PTFE material is increasing with the increase of the content of PTFE component, according to the following sequence: SIL < SIL-PTFE20 < SIL-PTFE50 < PTFE. It has been found from DSC data that the optimum physical properties of the SIL-PTFE system as antigraffiti coatings are observed for the highest content of entrapped PTFE macromolecules in the crosslinked SIL cages. In general, it can be concluded that the TA techniques are useful for characterization of hybrid polymer systems.
Presentation: invited oral at E-MRS Fall Meeting 2005, Symposium E, by Zbigniew Dobkowski
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-07-25 17:49 Revised: 2009-06-07 00:44