Kinetic micromechanics of polymer fracture

Abstract

A B S T R A C T Direct physical methods were used for studying molecular fracture in stressed polymers. The macromolecular ruptures were detected by electron paramagnetic resonance, infrared spectroscopy, and mass spectrometry. Nucleation of incipient submicrocracks was registered by small-angle X-ray scattering and light scattering. All methods were used to study fracture kinetics at different stresses and temperatures. The thermal fluctuation nature of microruptures is verified and the activation energy for the elementary events of polymeric fracture is estimated. This energy coincides with the activation energy for macrorupture evaluated in the study of the lifetime of polymers. Chain chemical reactions of stresses macromolecules disruption are proved to take part in formation of incipient cracks. The main features of the micromeehanics of polymer fracture are listed.

On the potential of lignin-containing cellulose nanofibrils (LCNFs): a review on properties and applications

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