Free volume characteristics of 2, 2‐bistrifluoromethyl ‐4,5‐difluoro‐1,3‐dioxole‐ co ‐tetrafluoroethylene copolymers: Effect of composition and molecular weight

2021 ◽  
Author(s):  
Dayang Yu ◽  
Guoliang Mao ◽  
Huaixun Cai ◽  
Shuhua Wang ◽  
Jiandang Liu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Free Volume ◽  
Volume Characteristics

Effect of the casting solvent on the free-volume characteristics and gas permeability of poly[1-(trimethylsilyl)-1-propyne] membranes

2002 ◽  
Vol 87 (3) ◽  
pp. 497-501 ◽  
Author(s):  
Jing Jing Bi ◽  
C. L. Wang ◽  
Y. Kobayashi ◽  
K. Ogasawara ◽  
A. Yamasaki
Keyword(s):  
Free Volume ◽  
Gas Permeability ◽  
Volume Characteristics

The Equation of State and the Temperature, Pressure, and Shear Dependence of Viscosity for a Highly Viscous Reference Liquid, Dipentaerythritol Hexaisononanoate

2016 ◽  
Vol 139 (1) ◽  
Author(s):  
Scott Bair ◽  
Tsuyoshi Yamaguchi
Keyword(s):  
Molecular Weight ◽  
Shear Stress ◽  
Equation Of State ◽  
High Molecular Weight ◽  
Free Volume ◽  
Newtonian Limit ◽  
Scaling Models ◽  
The Difference ◽  
Better Than ◽  
Low Shear

Measurements are reported for dipentaerythritol hexaisononanoate (DiPEiC9) of pressure–volume–temperature (pVT) response to pressures to 400 MPa and temperatures to 100 °C, and of viscosity at pressures to 700 MPa and temperatures to 90 °C and shear stress to 18 MPa. These data complement the low-shear viscosities published by Harris to pressures to 200 MPa and the compressions by Fandiño et al. to 70 MPa. The improved Yasutomi correlation reproduces all viscosity measurements with accuracy better than the Doolittle free volume and the Bair and Casalini thermodynamic scaling models which require an equation of state (EoS). The interaction parameter for thermodynamic scaling, γ = 3.6, is less than that reported by Harris (γ = 4.2) and the difference is primarily in the choice of EoS. The shear stress at the Newtonian limit, about 6 MPa, is exceptionally large given the high molecular weight of DiPEiC9. The large Newtonian limit is also seen in the oscillatory shear response.

Correlations between free volume characteristics and pervaporation permeability of novel PVA–GPTMS hybrid membranes

2006 ◽  
Vol 275 (1-2) ◽  
pp. 97-104 ◽  
Author(s):  
Fubing Peng ◽  
Lianyu Lu ◽  
Honglei Sun ◽  
Yanqiang Wang ◽  
Hong Wu ◽  
...  
Keyword(s):  
Free Volume ◽  
Hybrid Membranes ◽  
Volume Characteristics

The effect of the crosslinking density of cured epoxide polymers on the free-volume characteristics

1980 ◽  
Vol 22 (9) ◽  
pp. 2145-2149 ◽  
Author(s):  
T.I. Ponomareva ◽  
A.I. Yefremova ◽  
Yu.N. Smirnov ◽  
V.I. Irzhak ◽  
E.F. Oleinik ◽  
...  
Keyword(s):  
Free Volume ◽  
Crosslinking Density ◽  
Epoxide Polymers ◽  
Volume Characteristics

Investigation of free volume characteristics of the interfacial layer in poly(methyl methacrylate)–alumina nanocomposite and its role in thermal behaviour

RSC Advances ◽  
2016 ◽  
Vol 6 (72) ◽  
pp. 67997-68004 ◽  
Author(s):  
S. K. Sharma ◽  
K. Sudarshan ◽  
M. Sahu ◽  
P. K. Pujari
Keyword(s):  
Methyl Methacrylate ◽  
Size Distribution ◽  
Free Volume ◽  
Thermal Behaviour ◽  
Interfacial Layer ◽  
Poly Methyl Methacrylate ◽  
Alumina Particles ◽  
Alumina Composites ◽  
Volume Characteristics

A denser interfacial layer with smaller size nanoholes and narrower size distribution around alumina particles in PMMA–alumina composites.

Free volume in PEP-silica nanocomposites with varying molecular weight

Polymer ◽  
2014 ◽  
Vol 55 (1) ◽  
pp. 143-149 ◽  
Author(s):  
Christian Ohrt ◽  
Tönjes Koschine ◽  
Klaus Rätzke ◽  
Franz Faupel ◽  
Lutz Willner ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Free Volume ◽  
Silica Nanocomposites

Anionic surfactant-doped Pebax membrane with optimal free volume characteristics for efficient CO 2 separation

2015 ◽  
Vol 493 ◽  
pp. 460-469 ◽  
Author(s):  
Yifan Li ◽  
Xueqin Li ◽  
Hong Wu ◽  
Qingping Xin ◽  
Shaofei Wang ◽  
...  
Keyword(s):  
Free Volume ◽  
Anionic Surfactant ◽  
Volume Characteristics

Molecular Packing of Carbohydrate Oligomer Encapsulants - A Free Volume Perspective

2012 ◽  
Vol 733 ◽  
pp. 96-99 ◽  
Author(s):  
Mina Roussenova ◽  
Sam Townrow ◽  
Mathieu Murith ◽  
Job Ubbink ◽  
M. Ashraf Alam
Keyword(s):  
Molecular Weight ◽  
Positron Annihilation ◽  
Free Volume ◽  
Glassy State ◽  
Low Molecular Weight ◽  
Hole Size ◽  
Positron Annihilation Lifetime ◽  
Food Industries ◽  
Molecular Organisation ◽  
Complex Manner

Positron annihilation lifetime spectroscopy (PALS) is used in conjunction with dilatometry to analyse the effects of water and low molecular weight diluents (maltose and glycerol) on the molecular organisation and density of carbohydrate oligomers commonly used in the pharmaceutical and food industries for the formulation of encapsulation matrices. In the glassy state, both maltose and glycerol act as packing enhancers, causing a non-linear decrease in the average molecular hole size of the carbohydrate matrices. Water exists in a highly non-ideal state in these systems and it alters the molecular organisation of the matrices in a complex manner, whereby it can act either as an anti-plasticiser or a plasticiser, depending on the level of hydration.

Sign in / Sign up

Export Citation Format

Share Document