Description of thermal and mechanical properties of drawn polymers over a wide temperature range

Abstract

Temperature dependencies of the thermal expansion coefficient for segments of macromolecular helices, ol(T), were obtained for polymers by infrared (IR) spectroscopy. It was shown that the a ( T ) are complicated (nonlinear) over a wide temperature range. Wunderlich and Bauer's idea concerning "freezing out" of normal vibrations of polymer chains was used to describe them. It was shown that the substitution of the classical rather than quantum statistics for both torsional and bending vibrational modes of macromolecules causes complications in a ( T ) . Mechanical properties of drawn linear polymers are connected with the thermal expansion. Therefore, such an approach may be used to describe the temperature dependence of Young's modulus and failure strength for drawn polymers in the range from cryogenic to melting temperatures.

Kinetics of the thermally induced precursor curing to polymer via statistical analysis of TEM images

“…[14], both fracture and elasticity of solids are controlled by thermal fluctuations. Therefore temperature/time dependence of both strength and Young's modulus are closely related and described by identical Arrhenius type equations [14]. An empirical correlation of dynamic Young's modulus E 0 and r is known to be given as [15] …”

“…In the kinetic concept of fracture [13,14], the strength of solids, r, is determined by the parameters of the atom coupling (elasticity E, equilibrium distance r 0 , and ultimate strain e * ), the free path length of phonons K, the activation energy of fracture U 0 , and the time-to-fracture s …”

Долговечность Полимерных Композитов

“…Такие же зависимости наблюдались и для других неориентиро-ванных полимеров и адгезионных соединений [40][41][42][43].…”

“…торсионных и из-гибных мод колебаний полимеров [41,42]. Видно, что вычисленные и измеренные значения частот ν t и ν b совпадают.…”

Problems of the Physics of the Oriented State of Polymers

“…(3) Two other quantum effects are observed by Bronnikov and Vettegren [32]. They consist in the coincidence of Debye temperatures for torsional and bending vibration modes (as revealed from IR or Raman spectra) with temperatures of /3-and a-transitions treated as relaxational (kinetic) transitions and being such in reality [8].…”