Application of time-temperature-stress superposition principle on the accelerated physical aging test of polycarbonate

Abstract

The effect of physical aging on the polymer mechanical properties is very important for long-term safety assessment of engineering application. In this paper, the physical aging tests of polycarbonate (PC) were conducted systemically under different temperature and uniaxial tensile stress level. It was shown that both temperature and stress have obvious accelerated effect on the physical aging of PC. The higher the temperature and stress level are, the faster the aging process is. To predict the longterm behavior after physical aging using the short-term test results of PC, the elongation-at-break was chosen as the index of the severity of physical aging. An Arrheniustype time-temperature-stress superposition principle (TTSSP) was proposed to evaluate long-term performance using short-term test data. Using the proposed method, time and cost can be dramatically reduced for the assessment of long-term physical aging performance of polymeric material.

Tunability and molecular weight dependence of the physical aging behavior of polystyrene and poly(methyl methacrylate) films

“…During physical aging, the specific enthalpy and specific volume of the glass decrease with aging time 8–10 . These changes lead to a time dependence of mechanical and physical properties, for example, increases in density, brittleness and elastic modulus and reductions in permeability, impact strength, creep rate, fracture energy, and ultimate elongation 1–22 . In particular, the volume contraction associated with the physical aging of a glassy polymer can result in a permeability decrease of ca.…”

On creep, recovery, and stress relaxation of carbon fiber‐reinforced epoxy filament wound composites

“…Prediction of long‐term creep from short‐term experimental tests can be reached by using, for instance, the time–temperature superposition principle (TTSP) . However, most of these studies evaluate short fiber composites . For long fiber‐reinforced composites, creep is largely more prominent in the polymeric matrix due to its viscoelastic nature.…”

Accelerated aging test of hydrogenated nitrile butadiene rubber using the time–temperature–strain superposition principle

“…27 Zhu et al discussed the possible mechanisms of accelerated aging of polymers under applied stress. 28 A time-temperature-stress superposition principle, 29 borrowing the idea from accelerating studies of long-term creep, [30][31][32][33][34][35][36][37] has been successfully proposed to study the acceleration effect of applied stress on the aging of polycarbonate. While little work can be found in the literature concerning the effect of applied strain on the aging process, many rubber components are actually subjected to a prescribed strain rather than stress for certain applications, for example as seals and gaskets.…”