On the molecular mechanism of self-healing of glassy polymers

The chain ends concentrations in a near-surface nanometre-thick layer of such representative amorphous polymers as atactic polystyrene (PS), poly(2,6-dimethyl-1,4-phenylene oxide) (PPO), and poly(methyl methacrylate) (PMMA) have been estimated. It has been shown that the number of the chain ends located in that layer is sufficient to give rise to the development of the intermolecular van-der-Waals bonds via the interdiffusion of the chain ends across the interface between the two contacting polymer samples, even at the healing temperatures that are lower by some tens or even a hundred degrees of Kelvin with respect to the bulk glass transition temperatures, making the interface capable to bear the mechanical load. The validity of the molecular mechanism of self-healing of amorphous polymers with glassy bulk proposed earlier has been confirmed.