The Impact of Crystalline Phase Morphology on the Water-Promoted Electrorheological Effect of Polysaccharides

To produce a tough material for application demanding high impact resistance and low moisture absorption, melt blending of Nylon12 (Polyamide 12, PA12) and natural rubber (NR) was carried out in a brabender plasticorder at 210 °C with rotor speed of 70 rpm in the presence of polystyrene/maleated natural rubber (PS/MNR) blend as a compatibilizer. The effect of compatibilizer content (1, 3, 5, 7 and 10 phr) on phase morphology, thermal, and mechanical properties of [Nylon12/NR]/[PS/MNR] blends was investigated by using SEM, DSC, and Izod impact tester, respectively. The result revealed that PS/MNR blend improved the compatibility of Nylon12/NR blends efficiently due to the presence of amide linkage at the interfaces from the reaction between the reactive groups of MNR and the NH2 end groups of Nylon12 during mixing. A fine phase morphology (good dispersion and small dispersed phase size of NR domains in Nylon12 matrix) of [Nylon12/NR]/[PS/MNR] blends was observed at the optimum compatibilizer content of 7 phr, relating to the improvement of mechanical property. The impact energy of [Nylon12/NR]/[PS/MNR] blends was 503 J/m higher than that of neat Nylon12 (115 J/m) and Nylon12/NR binary blend (241 J/m) due to the toughening effect of rubber and proper morphology. The melting temperature of all blends did not change obviously from thermal analysis. However, the presence of rubber particle obstructed the crystallization of Nylon12 phase, leading to the decreasing of %crystallinity from 93% to around 70%.

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Crystalline Phase Morphology in Polymer/Organoclay Nanocomposites

Physics and Chemistry of Classical Materials ◽

10.1201/b17786-21 ◽

2014 ◽

pp. 175-182

Keyword(s):

Crystalline Phase ◽

Phase Morphology

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The importance of phase morphology for rheology of ferropericlase-bridgmanite mixtures

10.5194/egusphere-egu21-4384 ◽

2021 ◽

Author(s):

Marcel Thielmann ◽

Gregor Golabek ◽

Hauke Marquardt

Keyword(s):

Lower Mantle ◽

Mantle Convection ◽

Effective Viscosity ◽

Large Scale ◽

Numerical Models ◽

Phase Morphology ◽

Strong Impact ◽

Analytical Approximations ◽

The Impact ◽

Strong Control

<p>The rheology of the Earth&#8217;s lower mantle is poorly constrained due to a lack of knowledge of the rheological behaviour of its constituent minerals. In addition, the lower mantle does not consist of only a single, but of multiple mineral phases with differing deformation behaviour. The rheology of Earth&#8217;s lower mantle is thus not only controlled by the rheology of its individual constituents (bridgmanite and ferropericlase), but also by their interplay during deformation. This is particularly important when the viscosity contrast between the different minerals is large. Experimental studies have shown that ferropericlase may be significantly weaker than bridgmanite and may thus exert a strong control on lower mantle rheology.</p><p>Here, we thus explore the impact of phase morphology on the rheology of a ferropericlase-bridgmanite mixture using numerical models. We find that elongated ferropericlase structures within the bridgmanite matrix significantly lower the effective viscosity, even in cases where no interconnected network of weak ferropericlase layers has been formed. In addition to the weakening, elongated ferropericlase layers result in a strong viscous anisotropy. Both of these effects may have a strong impact on lower mantle dynamics, which makes is necessary to develop upscaling methods to include them in large-scale mantle convection models. We develop a numerical-statistial approach to link the statistical properties of a ferropericlase-bridgmanite mixture to its effective viscosity tensor. With this approach, both effects are captured by analytical approximations that have been derived to describe the evolution of the effective viscosity (and its anisotropy) of a two-phase medium with aligned elliptical inclusions, thus allowing to include these microscale processes in large-scale mantle convection models.</p>

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Effects of Phase Morphology on Mechanical Properties: Oriented/Unoriented PP Crystal Combination with Spherical/Microfibrillar PET Phase

Polymers ◽

10.3390/polym11020248 ◽

2019 ◽

Vol 11 (2) ◽

pp. 248 ◽

Cited By ~ 5

Author(s):

Dashan Mi ◽

Yingxiong Wang ◽

Maja Kuzmanovic ◽

Laurens Delva ◽

Yixin Jiang ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Ethylene Terephthalate ◽

Phase Morphology ◽

Mechanical Recycling ◽

Immiscible Blends ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene ◽

The Impact

In situ microfibrillation and multiflow vibrate injection molding (MFVIM) technologies were combined to control the phase morphology of blended polypropylene (PP) and poly(ethylene terephthalate) (PET), wherein PP is the majority phase. Four kinds of phase structures were formed using different processing methods. As the PET content changes, the best choice of phase structure also changes. When the PP matrix is unoriented, oriented microfibrillar PET can increase the mechanical properties at an appropriate PET content. However, if the PP matrix is an oriented structure (shish-kebab), only the use of unoriented spherical PET can significantly improve the impact strength. Besides this, the compatibilizer polyolefin grafted maleic anhydride (POE-g-MA) can cover the PET in either spherical or microfibrillar shape to form a core–shell structure, which tends to improve both the yield and impact strength. We focused on the influence of all composing aspects—fibrillation of the dispersed PET, PP matrix crystalline morphology, and compatibilized interface—on the mechanical properties of PP/PET blends as well as potential synergies between these components. Overall, we provided a theoretical basis for the mechanical recycling of immiscible blends.

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Effect of the annealing procedure and the molecular weight on the crystalline phase morphology and thermal properties of polylactide

Polymer International ◽

10.1002/pi.5887 ◽

2019 ◽

Vol 68 (10) ◽

pp. 1767-1775 ◽

Cited By ~ 1

Author(s):

Martí Hortós ◽

Jon Anakabe ◽

Alex Arrillaga ◽

Sebastián Espino ◽

Jordi J Bou

Keyword(s):

Molecular Weight ◽

Thermal Properties ◽

Crystalline Phase ◽

Phase Morphology ◽

Annealing Procedure

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Crystalline-Phase Switching in Heterostructured Ga(As,P) Nanowires under the Impact of Elastic Strains

Semiconductors ◽

10.1134/s1063782620100267 ◽

2020 ◽

Vol 54 (10) ◽

pp. 1320-1324

Author(s):

N. V. Sibirev ◽

Yu. S. Berdnikov ◽

V. N. Sibirev

Keyword(s):

Crystalline Phase ◽

Phase Switching ◽

The Impact ◽

Elastic Strains

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Crystalline and Lamellar Structure of Polypropylene Fibrillated Fibres

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.203-204.439 ◽

2013 ◽

Vol 203-204 ◽

pp. 439-442

Author(s):

Marcin Bączek ◽

Czesław Ślusarczyk ◽

Jan Broda

Keyword(s):

Small Angle ◽

Crystalline Phase ◽

Lamellar Structure ◽

Draw Ratio ◽

Crystallinity Index ◽

Orientation Factor ◽

Processing Conditions ◽

X Ray ◽

X Ray Scattering ◽

The Impact

The effects of processing conditions on the structure of polypropylene fibrillated fibres were studied using a combination of wide- and small-angle X-ray scattering methods. In particular the impact of selected stages of processing on the crystalline and lamellar structure of PP were analyzed. It was stated that crystalline phase is built from α crystals. The crystallinity index as well as the Herman orientation factor of the crystalline phase is found to have a correlation only with the draw ratio of the PP film. The lamellar structure also changes with the draw ratio.

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