Differential Scanning Calorimetry (DSC) and Synchrotron X-ray Diffraction Study of Unmilled and Milled LiBH4: A Partial Release of Hydrogen at Moderate Temperatures

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.

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Synthesis and mesomorphic properties of calamitic malonates and cyanoacetates tethered to 4-cyanobiphenyls

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.8.40 ◽

2012 ◽

Vol 8 ◽

pp. 371-378 ◽

Cited By ~ 5

Author(s):

Katharina C Kress ◽

Martin Kaller ◽

Kirill V Axenov ◽

Stefan Tussetschläger ◽

Sabine Laschat

Keyword(s):

Differential Scanning Calorimetry ◽

Ambient Temperature ◽

Liquid Crystalline ◽

X Ray Diffraction ◽

Cyanoacetic Acid ◽

Scanning Calorimetry ◽

Isotropic Liquid ◽

X Ray ◽

Nematic Phases ◽

Mesomorphic Properties

4-Cyano-1,1'-biphenyl derivatives bearing ω-hydroxyalkyl substituents were reacted with methyl 3-chloro-3-oxopropionate or cyanoacetic acid, giving liquid-crystalline linear malonates and cyanoacetates. These compounds formed monotropic nematic phases at 62 °C down to ambient temperature upon cooling from the isotropic liquid. The mesomorphic properties were investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction (WAXS).

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Inosose-Flüssigkristalle / Inosose Liquid Crystals

Zeitschrift für Naturforschung B ◽

10.1515/znb-1990-0730 ◽

1990 ◽

Vol 45 (7) ◽

pp. 1084-1090 ◽

Cited By ~ 23

Author(s):

Klaus Praefcke ◽

Bernd Kohne ◽

Andreas Eckert ◽

Joachim Hempel

Keyword(s):

Differential Scanning Calorimetry ◽

Liquid Crystal ◽

High Temperature ◽

Liquid Crystalline ◽

Structural Features ◽

Lyotropic Liquid Crystal ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Alkyl Chains

Six S,S-dialkyl acetals 2a-f of inosose (1), tripodal in structure, have been synthesized, characterized and investigated by optical microscopy and differential scanning calorimetry (d.s.c.). The four S,S-acetals 2c-f with sufficiently long alkyl chains are thermotropic liquid crystalline; 2 e and 2 f are even dithermomesomorphic. Each of these four inosose derivatives 2c-f exhibits monotropically a most likely cubic mesophase (MI); in addition 2e and 2f show enantiotropically a hexagonal mesophase (Hx) with a non-covalent, supramolecular H-bridge architecture. Whereas the nature of the optically isotropic mesophase MI needs further clarification the stable high temperature mesophase Hx of 2 e and 2 f has been established by a miscibility test using a sugar S,S-dialkyl acetal also tripodal in structure and with a Hx phase proved by X-ray diffraction, but in contrast to 2 with an acyclic hydrophilic part. Similarities of structural features between the Hx-phases of 2e and 2f as well as of other thermotropic and lyotropic liquid crystal systems are discussed briefly.

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Formation of Pharmaceutical Salts and Cocrystals via Vapour-Assisted Tumbling (VAT) – A Solvent Efficient Process with Potential Industrial Applications

10.33774/chemrxiv-2021-qgnfh-v2 ◽

2021 ◽

Author(s):

Alexander J. Stirk ◽

Fabio E. S. Souza ◽

Jenny Gerster ◽

Fatemeh M. Mir ◽

Avedis Karadeolian ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

Environmental Impact ◽

Industrial Applications ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

New Techniques ◽

X Ray ◽

Industry Standard ◽

Pharmaceutical Salts ◽

Solid Form

Crystallisations on both the academic and industrial scale often use large volumes of solvent. In order decrease the environmental impact of such processes, new techniques must be discovered that increase the efficiency of the solvents used. Introduced here is a process that combines repurposed industry standard hardware and aspects of mechanochemistry to produce a technique we call “Vapour Assisted Tumbling” (VAT). Pharmaceutical and well-known cocrystals and salts were formed by tumbling the coformers in an atmosphere of vaporised solvent, in this study, methanol (MeOH). This was done inside a custom built analogue of an industrial rotary cone dryer (RCD). It was found that a desired solid form could be obtained as monitored by powder X-ray diffraction and differential scanning calorimetry. By repurposing industrial RCDs, it is feasible that solid forms can be crystallised with both minimal and reusable/recyclable solvent – drastically lowering the environmental impact of such transformations.

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