Spherulitic morphology
WebAvrami exponent (n) of the PLA, PLA-3JO and PLA-7JO was found to be 4.08, 3.28 and 3.09, respectively, suggesting that the nonisothermal cold crystallizations of the plasticized PLA follow a heterogeneous nucleation and three-dimensional spherulitic growth, as … WebThe evolution of the spherulitic morphology, commonly encountered during the solidification of semicrystalline materials, is modeled by taking into account the transport …
Spherulitic morphology
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Spherulites are composed of highly ordered lamellae, which result in higher density, hardness, but also brittleness when compared to disordered regions in a polymer. The lamellae are connected by amorphous regions which provide elasticity and impact resistance. Zobraziť viac In polymer physics, spherulites (from Greek sphaira = ball and lithos = stone) are spherical semicrystalline regions inside non-branched linear polymers. Their formation is associated with crystallization of polymers from … Zobraziť viac Mechanical Formation of spherulites affects many properties of the polymer material; in particular, crystallinity, density, tensile strength and Young's modulus of polymers increase during spherulization. This increase is due … Zobraziť viac If a molten linear polymer (such as polyethylene) is cooled down rapidly, then the orientation of its molecules, which are randomly aligned, curved and entangled remain frozen and the solid has disordered structure. However, upon slow cooling, some polymer … Zobraziť viac • Crystallization of polymers Zobraziť viac • G. W. Ehrenstein; Richard P. Theriault (2001). Polymeric materials: structure, properties, applications. Hanser Verlag. ISBN 1-56990-310-7. Zobraziť viac WebTh ey also observed a skin-core variation in morphology, with the skin dominated by amorphous polypropylene and a-phase crystalline material. Their work did not consider any effects that might be introduced by varying the mold wall material. Molds for high volume ( - lo6 parts) production runs have been traditionally fabricated from ...
Web26. apr 2016 · The influence of interfaces on the morphology of flat spherulites of isotactic polystyrene (iPS) grown in thin films on liquid substrates was investigated. Amorphous … Web3. okt 2002 · To simulate the collapse of the original spherulitic morphology, the radii of the spheres decrease at a rate dependent on the shear stress imposed on them by the surrounding network. This results in time-dependent behavior. The resultant large strain viscoelastic model is implemented in a commercial finite element code and used to …
Web1. jan 2007 · The morphology of isotactic polypropylene is investigated using scanning electron microscopy. The structure is modified by the addition of specific nucleating …
WebNonequilibrium spherulitic magnetite in the Ryugu samples GEOCHIMICA ET COSMOCHIMICA ACTA Elena Dobrica, Hope A. Ishii, John P. Bradley, Kenta Ohtaki, Adrian J. Brearley, Takaaki Noguchi, Toru Matsumoto, Akira Miyake, Yohei Igami, Mitsutaka Haruta, Hikaru Saito, Satoshi Hata, Yusuke Seto, Masaaki Miyahara ...
WebThe morphology of homocrystals and stereocomplex crystals in the blends was examined using a hot-stage polarising microscope and a scanning electron microscope. The DSC results showed that homocrystals and stereocomplex crystals were present in all LD blends except that with 50 wt% PLLA/50 wt% PDLA; in this blend, only stereocomplex crystals ... portable bath transfer bench in pocatello idWebThe Effect of Annealing Treatments on Spherulitic Morphology and Physical Ageing on Glass Transition of Poly Lactic Acid (PLLA) El-Hadi Ahmed Mohamed Materials Sciences … irpf 2022 para download baixarWebMorphological consequences of a localized diffusion of segregated species at crystal growth fronts have been studied in two specific contexts: (1) variation of texture in … irpf 2022 isento