Modes of action of terpene penetration enhancers in human skin; Differential scanning calorimetry, small-angle X-ray diffraction and enhancer uptake studies

1996 ◽  
Vol 127 (1) ◽  
pp. 9-26 ◽  
Author(s):  
Paul A. Cornwell ◽  
Brian W. Barry ◽  
Joke A. Bouwstra ◽  
Gert S. Gooris
Keyword(s):  
Differential Scanning Calorimetry ◽  
Human Skin ◽  
Small Angle ◽  
Penetration Enhancers ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Modes Of Action ◽  
Uptake Studies

Heterocyclic and aromatic based polyurethane scaffolds: morphology and crystallinity studied by X-ray diffraction, small-angle X-ray scattering and differential scanning calorimetry

2013 ◽  
Vol 46 (4) ◽  
pp. 980-992 ◽  
Author(s):  
Tarek M. Madkour ◽  
Sahar K. Mohamed
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Small Angle ◽  
Aromatic Diamine ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
X Ray Scattering ◽  
Chain Extenders ◽  
Ray Scattering

The morphology, crystallinity and X-ray diffraction of speciality heterocyclic and aromatic based polyurethane and poly(urethane–urea) elastomers synthesized via a one-shot polymerization method were studied. The samples were chain extended by mixtures of aliphatic diols and furanic or aromatic diamine chain extenders. Small-angle X-ray scattering (SAXS) measurements confirmed the results obtained by differential scanning calorimetry (DSC) and revealed the presence of phases with sharp phase boundaries. The SAXS patterns are best fitted with a model that consists of liquid-like ordered polydisperse spheres. Most of the samples were shown to be poorly crystalline, but some soft-phase crystals do exist and these melted at about 353 K as confirmed by DSC and temperature-dependent wide-angle X-ray diffraction. Annealing at 273 K did not affect the thermal stability but influenced the morphology of the samples. The effect of annealing on the samples of poly(urethane–urea) extended using diamine chain extenders was smaller than that for polyurethane samples, which indicates a much higher thermal stability of the poly(urethane–urea) samples owing to the formation of bidentate hydrogen-bond networks across the urea groups.

scholarly journals Phase transition behavior and deformation mechanism of polytetrafluoroethylene under stretching

RSC Advances ◽  
2021 ◽  
Vol 11 (63) ◽  
pp. 39813-39820
Author(s):  
Cong Luo ◽  
Jingke Pei ◽  
Wenyue Zhuo ◽  
Yanhua Niu ◽  
Guangxian Li
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Small Angle ◽  
Deformation Mechanism ◽  
X Ray Diffraction ◽  
Phase Transition Behavior ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transition Behavior ◽  
X Ray Scattering

The deformation mechanism and phase transition behavior of polytetrafluoroethylene (PTFE) under stretching conditions (25, 50, 100 °C) were investigated by using differential scanning calorimetry (DSC), small angle X-ray scattering (SAXS), and X-ray diffraction (XRD).

Research on compatibility and surface of high impact bio-based polyamide

2021 ◽  
pp. 095400832110055
Author(s):  
Yang Wang ◽  
Yuhui Zhang ◽  
Yuhan Xu ◽  
Xiucai Liu ◽  
Weihong Guo
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Differential Scanning Calorimetry ◽  
Crystallization Behavior ◽  
High Impact ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Scanning Electron

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.

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

2012 ◽  
Vol 8 ◽  
pp. 371-378 ◽  
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).

Sign in / Sign up

Export Citation Format

Share Document