The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this study, Fourier transform infrared spectroscopy, synchrotron small-angle and wide-angle X-ray scattering were employed to reveal the underlying mechanism leading to conformational reorganization during mesomorphic-monoclinic phase transition. Results indicated that conformation reorganization occurred from 50 to 130 °C, evidenced by conformational infrared bands at 800 and 841 cm−1. The conformation...
The plastic deformation behavior of isotactic polypropylene (iPP) film is studied with in-situ Fourier transformation infrared microspectroscopic imaging (FTIRI). During uniaxial tensile test, spatial distributions of crystallinity and orientations are obtained in necking region (NR), transition front (TF) and non-necking region (NNR). A low valley of crystallinity exists at TF, while both NNR and...
In this work extension induced crystallization of end-linked polyethylene oxide (PEO) network was investigated with in-situ small angle X-ray scattering (SAXS) and rheological measurement. The coupling between crystallinity and stress of crosslinked network makes the morphology time dependent. With a large strain the structure evolution in the stretched network is found to follow a two-stage process:...
The crystal–crystal transition of isotactic polybutene-1 (iPB-1) from form II to I at room temperature is investigated with in-situ Fourier transform infrared spectroscopy (FTIR), Fourier transformation infrared microspectroscopic imaging (FTIRI) and synchrotron radiation scanning X-ray micro-diffraction (SR-μSXRD). The transition rate from form II to I shows a non-monotonic correlation with crystallization...
With three polymers (poly(1-butene), isotactic polypropylene and syndiotactic polypropylene) as model systems, the effect of extensional strain on the nucleation rate was studied using a home-made miniature extensional rheometer and in-situ X-ray scattering. A non-monotonic correlation between nucleation rate and strain is observed around rheological yield point. Increasing strain leads to an increase...
The deformation behaviors of three types of polyethylene (PE) with different molecular weights and short chain branch contents were studied by in-situ Fourier transformation infrared microspectroscopic imaging (FTIRI) with a Focal Plane Array (FPA) detector during uniaxial tensile test. The crystal orientation distributions within a 250 × 250 μm 2 region during tensile test were obtained,...
Drawing-induced α crystal–mesophase transition of isotactic polypropylene (iPP) was studied with in situ wide angle X-ray diffraction (WAXD) during the true stress–true strain tensile testing. The true stress–true strain and in situ WAXD measurements revealed that the critical stress for the crystal–mesophase transition has a nearly linear correlation with lamellar thickness irrespective of the sample...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.