Philippe Colomban

Sorbonne Universités, UPMC Paris 06, MONARIS umr8233 CNRS, Paris, France


A very important characteristic of the mechanical properties is that they do not only depend from the matter, but also from the object: in a rough description, as a function of the 'quality' of the sample processing, it is more or less possible to explore the potential of the mechanical properties of the material. We will review the broad possibilities that Raman – and some extended IR- microspectrometry in combination with tensile/compressive solicitations offer in the study of the (nano)texture and the (nano)mechanical behaviour of advanced and natural fibres by closely analysing the spectra in two wavenumber ranges that are generally ignored in polymer materials studies, the very low (< 200 cm-1) and the very high ( ~3500 cm-1) wavenumber ranges. Techniques of deuteration developed for the study of protonic conductors will be also dealt with. We will consider the most important synthetic (polyamides (PA 66), polyethyleneterephthalate (PET), polypropylene (PP), poly(paraphenylene benzobisoxazole (PBO), Kevlar) and natural (keratin/hair, silkworm and spider silks) fibres. Vibrational spectroscopy is applied so as to differentiate between crystalline and amorphous macromolecules. These conclusions are then used to discuss the modifications induced by the application of a tensile or compressive stress, including the effects of fatigue. Detailed attention is paid to the inter-chain coupling for which the importance of hydrogen bonding is reconsidered. The significant role of the ‘‘amorphous’’ bonds/domains in the process of fracture/fatigue is shown.

Ph. Colomban, Understanding the nano- and macromechanical behaviour, the failure and fatigue mechanisms of advanced and natural polymer fibres by Raman/IR microspectrometry, Adv. Nat. Sci.: Nanosci. Nanotechnol. 4 (2013) 013001
M. Wojcieszak, A. Percot, S. Noinville, G. Gouadec, Ph. Colomban, Origin of the variability of the mechanical properties of silk fibres:4. Order/cristallinity along silkworm and spider fibres, J. Raman Spectrosc. 45[10] (2014) 895-902.