Characterization of POSS-sorbitol non-covalent complexes, a new class of polymer composite materials

摘要

The addition of nanometer-size inorganic particles to an organic polymer improves significantly the thermal and tensile properties of the polymer itself. The degree of this effect depends on the dispersion state of the inorganic material in the polymer. POSS has been considered to be the ideal inorganic material due to its thermal stability, size, and isotropic shape. The poor interaction between the hydrophilic POSS surfaces and hydrophobic polyolefins reduces its dispersion efficiency in such polymers. Since sorbitol-type nucleating agents can disperse and gel polymeric melts, they could be used as template for the dispersion of POSS via non-covalent interactions. This study is aimed at characterizing the POSS-sorbitol interaction by MS and ion mobility (IM-MS). The samples were dissolved in THF. Consecutively, MeOH was added to this solution in order to obtain a final concentration of 0.1 mg/mL in 1:1 (v:v) THF/MeOH. All MS measurements were carried out using a SYNAPT HDMS~(TM) quadrupole/time-of-flight (Q/oa-ToF) mass spectrometer (Waters, Beverly, MA) equipped with a Z-spray electrospray source. The ion mobility experiments were performed on the same instrument by activating the traveling wave (T-Wave) separation section located between the two analyzers. For the MS/MS studies of the complexes, in both MS and IM-MS mode, the collision energy applied was varied within 6-20 eV, depending on the type of complex (POSS-POSS or POSS-sorbitol) and stoichiometry.