(C) 2009 American Institute of Physics. [doi: 10.1063/1.3236511]“
“Long-chain branching polypropylene (LCB-PP) was achieved by reactive extrusion in the presence of bifunctional monomer [1,6-hexanediol diarylate (HDDA)] and peroxide of dicumyl peroxide (DCP). Influences of HDDA and DCP concentrations on the branching efficiency were comparatively evaluated. Fourier transformed infrared spectroscopy

(FTIR) results indicated that the grafting reaction took place, and HDDA has been grafted on PP skeleton. In comparison with initial PP, some modified samples showed lower melt flow index because of a large number of LCB in their skeleton. Several rheology plots were used to investigate the rheological properties of the initial PP and modified PPs, and the rheological characteristics confirmed the LCB in modified PPs selleck skeleton. DSC results showed that the crystallization

temperatures of modified PPs were higher than those of initial PP and degraded PP, suggesting that the modified PPs had long-chain branched structure. The contrastive investigation in the rheology of modified Selleck CBL0137 PPS suggested that proper concentrations of HDDA and DCP were more beneficial to producing LCB during reactive extrusion. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 2126-2135, 2009″
“A range of ion beam techniques have been used to fabricate a variety of photonic guiding structures in the well-known lithium niobate (LiNbO3 or LN) crystals that are of great importance in integrated photonics/optics. This paper reviews the up-to-date research Stem Cell Compound Library purchase progress of ion-beam-processed LiNbO3 photonic structures and reports on their fabrication, characterization,

and applications. Ion beams are being used with this material in a wide range of techniques, as exemplified by the following examples. Ion beam milling/etching can remove the selected surface regions of LiNbO3 crystals via the sputtering effects. Ion implantation and swift ion irradiation can form optical waveguide structures by modifying the surface refractive indices of the LiNbO3 wafers. Crystal ion slicing has been used to obtain bulk-quality LiNbO3 single-crystalline thin films or membranes by exfoliating the implanted layer from the original substrate. Focused ion beams can either generate small structures of micron or submicron dimensions, to realize photonic bandgap crystals in LiNbO3, or directly write surface waveguides or other guiding devices in the crystal. Ion beam-enhanced etching has been extensively applied for micro- or nanostructuring of LiNbO3 surfaces. Methods developed to fabricate a range of photonic guiding structures in LiNbO3 are introduced. Modifications of LiNbO3 through the use of various energetic ion beams, including changes in refractive index and properties related to the photonic guiding structures as well as to the materials (i.e.