Solid‐state nuclear magnetic resonance of the PA6/PC, PA6/PPO, and PA6/PC/PPO blends

Abstract

ABSTRACT:The effect of mixing time is very important to plasticization and/or occurrence of chemical reaction between polyamide 6/poly(propylene oxide), polyamide 6/ polycarbonate, and polyamide 6/polycarbonate/poly(propylene oxide) blends. The systems were investigated through solid-state carbon-13 cross-polarization magic angle spinning with variable contact time in the NMR experiment. In the systems, polycarbonate can prevent the antiplasticization effect already observed in the polyamide 6/ poly(propylene oxide) blend. Therefore, it was verified that the addition of polycarbonate in the polyamide 6/poly(propylene oxide) system causes a hardening of the blend. This fact can be attributed to the restriction of the mobility of the NH group, probably influenced by the type of interaction that occurs in the polyamide 6/polycarbonate/ poly(propylene oxide), due to the effect of poly(propylene oxide), which can be act as an interfacial agent promoting a better interaction between polyamide 6 and polycarbonate.

Solid State NMR

“…The temporal evolution of the transverse relaxation is fundamentally different from longitudinal, and it corresponds to a loss of phase coherence between the individual magnetic moment process in it, and, thus an increase of entropy. In many cases, solid sample loss phase coherence initially created by B 1 is due to direct interactions between the spin moments of individual [1][2][3][4][5][6][7][8][9][10].…”

“…However, they are dependent on the nature of the sample and the external magnetic field strength applied [7][8][9][10].…”

“…This variation in the MAS technique enables, in the case of amorphous polymers, that is, ethylene-co-vinyl acetate (EVA), identifies the region of increased molecular mobility, or distinguishes the mobility of different areas, which cause changes in the properties of the material [6][7][8][9][10].…”

“…This method relies on the transfer of polarization of a nucleus spin abundant, hydrogen nucleus The combined cross-polarization technique with the rotation of the sample at the magic angle and strong hydrogen decoupling (CPMAS), generating NMR spectra of solid high-resolution rare spin nuclei with increasing signal strength in a shorter analysis time than the MAS, considering that the hydrogen nucleus controls the relaxation process [1][2][3][4][5][6][7][8][9][10]13].…”

High‐resolution carbon‐13 nuclear magnetic resonance study of natural resins

“…High‐resolution solid‐state nuclear magnetic resonance (NMR) experiments can be used to characterize them in the solid phase by using the following methods: 13 C magic‐angle spinning (MAS); cross‐polarization with magic‐angle spinning (CPMAS); and cross‐polarization/magic‐angle spinning with dipolar dephasing (CPMASDD) spectroscopy 2–7. The application of faster MAS with short delay time permits detection of high‐speed molecular motions of individual components.…”