Extremely Stretchable Vitrimers

Vitrimers are covalent adaptable networks, having many interesting versatile abilities with unprecedented potentials. Here, the combination of a low-T_g polymer system with dioxaborolane metathesis is used to develop catalyst-free vitrimers that can be stretched to more than 8900× their original length at a moderate stretching rate (≈50 mm min^-1 ). Superstretchable vitrimers are prepared from biodegradable xylitol-based polyol oligomers and cross-linked by dioxaborolane linkages. They are also found to be remarkable in terms of mechanical strength and other properties, such as malleability, self-healing ability, puncture resistance, and processing stability. Furthermore, the repeated rearrangements of dioxaborolane linkages and hydrogen bonds give rise to efficient energy dissipation with a maximum efficiency of 88%, allowing the superstretchable vitrimers to be promising for energy absorbing applications.