Application of the exponential function to the description of viscoelasticity in some solid polymers

Garbarski, Jacek

doi:10.1016/0020-7403(89)90108-2

Cited by 2 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…( 1 1 ) g ( 7 ) = s 2 n ( s ) 2 G w (12) where s = 1/7. It seems sensible that if the 7-scale is converted into the M-scale utilizing Eq.…”

Section: Classic Equations Of Linear Viscoelasticitymentioning

confidence: 99%

The application of an exponential‐type function for the modeling of viscoelasticity of solid polymers

Garbarski¹

1992

Polymer Engineering & Sci

View full text Add to dashboard Cite

This paper presents some results of analytical work focused on finding the optimal description of the viscoelasticity of solid polymers. Memory functions of creep and relaxation are the basic functions in the constitutive equations. Applying a specific type of this kind of function is the purpose of this work. Based on the known exponential function, a new function called the “root function” has been created. Its very important feature is that the corresponding plots of spectra are of the same character as the curves of molecular weight distribution. The theory is verified by applying uniaxial creep tests. The experimental curves are compared with the numerical simulation based on the newly introduced root function. Apart from the purely phenomenological verification, the molecular weight distribution curves obtained by the traditional GPC (gel permeation chromatographic) method are compared with the spectra calculated analytically on the basis of the parameters calculated from the creep tests. A very good convergence of the curves confirms the selection of the memory function and the applied method.

show abstract

“…( 1 1 ) g ( 7 ) = s 2 n ( s ) 2 G w (12) where s = 1/7. It seems sensible that if the 7-scale is converted into the M-scale utilizing Eq.…”

Section: Classic Equations Of Linear Viscoelasticitymentioning

confidence: 99%

The application of an exponential‐type function for the modeling of viscoelasticity of solid polymers

Garbarski¹

1992

Polymer Engineering & Sci

View full text Add to dashboard Cite

show abstract

“…Due to the presence of the exponential terms, the generic functions of viscoelasticity are highly sensitive to the parameter values. Garbarski [14,15] utilized a systematic search algorithm to determine the constants of double exponential function from multistep rheological test data for various thermoplastic polymers. Chambers [6] and Chen [7] independently employed pattern search algorithms to evaluate the constants of multiple exponential functions from relaxation data including ramp loading.…”

Section: Introductionmentioning

confidence: 99%

On relevance of time-dependent Poisson’s ratio for determination of relaxation function parameters

Suchocki

Molak

2019

J Braz. Soc. Mech. Sci. Eng.

View full text Add to dashboard Cite

The current study concerns the determination of material constants of a three-dimensional linear viscoelastic model. It is assumed that the constitutive equation utilizes a Prony series as a memory function. A method for the evaluation of relaxation function parameters is presented which can be used for arbitrary loading histories. The proposed methodology is applied to the identification of the viscoelastic constants of acrylonitrile butadiene styrene (ABS). For that purpose, a number of rheological tests in tension have been performed on ABS standard dogbone specimens. The significance of the time-dependent Poisson's ratio for the determination of material parameters is investigated. It is found that taking into account the measurements of specimen's lateral contraction over time has a particularly strong influence on the identified values of parameters responsible for the bulk behavior. Several boundary value problems have been analyzed in order to assess the influence of the material parameter values on the obtained solutions. It is demonstrated that some oversimplifications assumed during the determination of viscoelastic constants can lead to a loss of precision or even wrong results.

show abstract

Application of the exponential function to the description of viscoelasticity in some solid polymers

Cited by 2 publications

References 0 publications

The application of an exponential‐type function for the modeling of viscoelasticity of solid polymers

The application of an exponential‐type function for the modeling of viscoelasticity of solid polymers

On relevance of time-dependent Poisson’s ratio for determination of relaxation function parameters

Contact Info

Product

Resources

About