In-situ synchrotron SAXS and WAXS investigations on deformation and α–β transformation of uniaxial stretched poly(vinylidene fluoride)

Abstract

In-situ synchrotron SAXS and WAXS investigations on deformation and a-b transformation of uniaxial stretched poly(vinylidene fluoride)

Direct Observations on Structure Evolutions in Polyamide 6 during Deformation at High Temperatures with WAXS and SAXS

“…Indeed using in situ synchrotron radiation X‐ray scattering techniques provides rich structure–property information for many semicrystalline polymers . Our previous works have endorsed the effectiveness and accuracy of synchrotron radiation techniques. In this article, by means of synchrotron radiation WAXS and SAXS, which are ideal analysis techniques to probe changes (1–1,000 Å) in structure, we found that the structure evolution above T g is quite different from that below T g .…”

“…This mechanism could weaken the increscent d ach evolution during deformation and then stalemate it. After a plateau stage, the quite stretched amorphous phase is at a disadvantage and the lamellar fragments are responsible for the fall of long spacing . The lamellar fragments arrange and diffuse in the amorphous phase that lead the SAXS scattering to present a structure with more lamellae and smaller long spacing.…”

In - situ synchrotron wide-angle X-ray diffraction as a rapid method for cocrystal/salt screening

“…The ultra-high intensity and brilliance dramatically enhance the time-resolution in real-time experiments with millisecond precision (Bilderback et al, 2005). Therefore, synchrotron radiation has become a powerful tool for probing subtle and complex structural changes in various sciences, such as chemistry, biology, physics, medicine and material science (Gonzalez et al, 2003;Guo et al, 2013;Nojima et al, 2014;Tafforeau et al, 2006). Noguchi et al (2014) employed synchrotron radiation to investigate the polymorphic transformation of clarithromycin form II crystals under acidic condition.…”

Effects of initial crystallization process on piezoelectricity of PVDF-HFP films

“…As for the influences of some key fabrication parameters, many previous works to date focused on the fabrication steps after initialization crystallization process (e.g., stretching and poling) [11,15,16]. Only a few works explored the influences of initial crystallization temperature on the phase structures of PVDF homopolymer.…”

“…Thus, the critical theme is to increase the fraction of β-phase in the polymer. To date, several traditional methods have been developed to improve the phase transformation from α-phase to β-phase, such as high pressure, stretching, poling, annealing, polymer blending [10,11,[13][14][15][16][17][18][19], etc. Among them, the most common and important one is the mechanical stretching in solution casting method.…”