The Experiment Measuring Method of Polymer Melt Bulk Modulus by PVT Principle

2013 ◽  
Vol 561 ◽  
pp. 75-79
Author(s):  
Hong Xu ◽  
Ke Han ◽  
Ying Liu ◽  
Da Ming Wu
Keyword(s):  
Bulk Modulus ◽  
Free Volume ◽  
Polymer Melt ◽  
Measuring Method ◽  
Reciprocity Principle ◽  
Free Volume Theory ◽  
Temperature And Pressure

Introduced a experiment measuring method of polymer melt bulk modulus. This method based on the PVT reciprocity principle of polymer melt. Depending on liquid attribute of polymer melt, which means pressure changing caused micro variety of volume of certain quality melt in sealed container, polymer melt bulk modulus under the different temperature and pressure could be measured. According with the Polymer Free Volume Theory, the result proved the scientificity of this method.

Thermo-Mechanical Investigation of Free Volume Theory for Polyamie-6

2016 ◽  
Vol 819 ◽  
pp. 580-584
Author(s):  
Jamal Umer ◽  
Ivan Saprounov ◽  
Igor Emri ◽  
Barbara Zupančič ◽  
Muhammad Wakil Shahzad
Keyword(s):  
Mechanical Properties ◽  
Free Volume ◽  
Polyamide 6 ◽  
Time Dependent ◽  
Effect Of Temperature ◽  
Free Volume Theory ◽  
Wlf Equation ◽  
Mechanical Investigation ◽  
Temperature And Pressure

Polymers always show time-dependent mechanical properties. In order to use polymers in engineering applications, long-term mechanical propertes should be characterized. Free volume theroy is the mostly used theory to predict and model the mechanical properties of polymers. The effect of temperature is modelled thorugh William-Landel-Ferry (WLF) equation, whereas, the combined effect of temperature and pressure is modelled by Filler-Moonan-Tschoegl (FMT) equation. Both of the models are based on free volume theory. A set of expermentations were performed to investigate the validity of free volume concpet for one of the most important engineering polymer; i.e. Polyamide-6.

Parameters of the free volume theory in glasses with trigonal local coordination

2001 ◽  
Vol 10 (0) ◽  
pp. 147-151
Author(s):  
Т. М. Мельниченко ◽  
Т. Д. Мельниченко ◽  
Я. Я. Коцак ◽  
Я. П. Куценко ◽  
П. П. Пуга
Keyword(s):  
Free Volume ◽  
Free Volume Theory ◽  
Local Coordination

Development of a Method for the Prediction of Pressure-Viscosity Coefficients of Lubricating Oils Based on Free-Volume Theory

1989 ◽  
Vol 111 (1) ◽  
pp. 121-128 ◽  
Author(s):  
C. S. Wu ◽  
E. E. Klaus ◽  
J. L. Duda
Keyword(s):  
Free Volume ◽  
Good Accuracy ◽  
Temperature Relationship ◽  
Free Volume Theory ◽  
Simple Method ◽  
Lubricating Oils ◽  
Viscosity Coefficients ◽  
Data Points

A simple method based on free-volume theory to predict the pressure-viscosity coefficients of liquid lubricants has been developed. The method only requires the viscosity-temperature relationship and the viscosity at the temperature of interest. The method provides good accuracy when it was tested for 162 data points for various fluid types over wide ranges of temperature and viscosity.

Diffusivity of solvents in semi-crystalline polyethylene using the Vrentas-Duda free-volume theory

2018 ◽  
Vol 38 (10) ◽  
pp. 925-931 ◽  
Author(s):  
Derek R. Sturm ◽  
Kevin J. Caputo ◽  
Siyang Liu ◽  
Ronald P. Danner
Keyword(s):  
Free Volume ◽  
Weight Fraction ◽  
Amorphous Region ◽  
Model Parameters ◽  
Crystalline Region ◽  
Free Volume Theory ◽  
Melt Temperature ◽  
Tortuosity Factor ◽  
Crystalline Polyethylene

Abstract Diffusion of penetrants in polyethylene below the melt temperature is heavily dependent on the crystallinity of the polyethylene, the temperature of the experiment, and the concentration of solvent in the polymer. As the crystallinity of the polyethylene increases, there is an increase in the path that the solvent must travel as the solvent cannot penetrate the tightly packed chains in the crystalline domain. This effect is typically accounted for by a tortuosity factor. In this work, a simple and effective characterization of the tortuosity factor based simply on the crystal weight fraction has been developed. Data have been collected for six polyethylenes having densities ranging from 0.912 to 0.961 g/cm3 and for three solvents – isopentane, cyclohexane, and 1-hexene. Diffusivity predictions have been obtained using the free-volume theory of Vrentas and Duda in conjunction with the new tortuosity factor. The polyethylenes had crystallinities varying from 40% to 82% effecting an approximately 60% change in the diffusivity. The decrease resulting from ignoring the crystallinity altogether was in some cases essentially a factor of 5. The error in the predicted diffusivities over all the systems was 25%. For cyclohexane, it is shown that the same model parameters characterize data below the melt temperature (in the semi-crystalline region) as well as above the melt temperature (in the amorphous region).

Free-volume theory coupled with modified group-contribution PC-SAFT for predicting the viscosities. II. Alcohols and their mixtures

2019 ◽  
Vol 502 ◽  
pp. 112298 ◽  
Author(s):  
Dong NguyenHuynh ◽  
My T. Luu ◽  
Xuan T.T. Nguyen ◽  
Chau T.Q. Mai ◽  
Siem T.K. Tran
Keyword(s):  
Free Volume ◽  
Group Contribution ◽  
Free Volume Theory
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