Results 271 to 280 of about 192,349 (315)
Some of the next articles are maybe not open access.
Time-Temperature Superposition
2016This chapter consists of three sections: the fundamentals, the geometric interpretation, and the algorithms of time-temperature superposition. The first section deals with the phenomenology, mathematical formulas, models for horizontal shift factor, and molecular explanation of time-temperature superposition.
openaire +2 more sources
Time-temperature superposition for partially crystalline polymers (polytetrafluoroethylene)
Polymer Mechanics, 1976Time-temperature superposition in the\(\mathop \varepsilon \limits^.\) = const regime can be applied to partially crystalline fluoroplastics with different specific volumes. There is a correlation between the variation of the specific volume and the relaxation processes in fluoroplastics.
Yu. F. Dunichev +2 more
openaire +2 more sources
Application of principle of time-temperature superposition in studying asphalts
Chemistry and Technology of Fuels and Oils, 19761. A method has been developed for application of the WLF principle of time-temperature superposition to describe the viscoelastic characteristics of asphalts. 2. In the example of determining the temperature dependence of undisturbed structure of asphalts, good agreement has been demonstrated between experimental results and values ...
A. A. Akhmetova +2 more
openaire +2 more sources
Time-temperature superposition for block copolymers
1971The proposition is made that simple time-temperature superposition should not be valid for block copolymers exhibiting multiple mechanical transitions; and an explanation of the time temperature behavior, which is more consistent with the behavior of the individual phases, is presented in terms of an equivalent mechanical model.
openaire +2 more sources
Stress relaxation and time/temperature superposition of polypropylene fibres
Polymer, 1995The viscoelastic properties of polypropylene fibres are investigated in a single-step stress relaxation test for small strains at temperatures between −50 and + 30 °C, thus well encompassing the glass transition temperature. For the analysis of the curves a formal two-component (TC) model is applied, which comprises an elastic and a viscoelastic ...
K.V. Schulz, F.-J. Wortmann
openaire +2 more sources
Time ? Temperature superposition for thermorheologically complex materials
Polymer Mechanics, 1975The shift factoraT for thermorheologically complex bodies is a function not only of temperature T but also of the deformation time t. A method is given for determining the vertical shift factor on the basis of macro-tests within the experimental time window.
openaire +2 more sources
Time-temperature superposition in the enthalpy relaxation study of polystyrene
Polymer Engineering & Science, 2016Enthalpy recovery measurement was used to study the physical aging behavior of a polystyrene. The aging experiments at temperatures (TA) near Tg were conducted with aging times (tA) ranging from several minutes to several days. The recovered enthalpy, ΔH(tA, TA), increased with tA, and then a plateau value of ΔHplate appeared in the long time aging ...
Shiho Kashiwabara +2 more
openaire +2 more sources
Time-temperature superposition in the α region of an epoxy resin
Journal of Macromolecular Science, Part B, 1970Abstract The relative merits of time-temperature superposition procedures (those of Leaderman, Tobolsky, Ferry, Kě, McCrum, and Morris) have been assessed for the glass-rubber (a) relaxation of an epoxy resin. Measurements of creep compliance in shear were made at temperatures between 24° and 190°C.
G. A. Pogany, N. G. McCrum
openaire +2 more sources
Geometric Interpretation of Linear Viscoelasticity and Time-Temperature Superposition
AIP Conference Proceedings, 2008Dynamic moduli data are considered as a curve on the plane of loss tangent and storage modulus. The curve can be parameterized by the material frequency which is defined as the arc length of the curve. The relationship between real frequency and the material frequency determines the horizontal and vertical shift factors.
Kwang Soo Cho +6 more
openaire +2 more sources
Time-Temperature Superposition in Heterophase Block Copolymers
1973The viscoelastic behavior of a styrene-butadiene-styrene block copolymer cast from several different solvents was studied in order to examine the validity of the time-temperature superposition principle in heterophase polymers. It is found that stress-relaxation isotherms over a wide temperature range can be easily superposed into smooth master curves.
A. Kaya, M. C. Shen, G. Choi
openaire +2 more sources