Relaxation map of a 100% green thermoplastic film. Glass transition and fragility

A 100% green thermoplastic obtained by extrusion of a mixture of wheat flour and plasticizers has been realized. The existence of two vitreous phases in this 100% green thermoplastic film has been pointed out by means of calorimetric measurements (Tg=−56 °C and Tg=10 °C) and confirmed by electron microscopy.The molecular dynamics have been investigated by means of DMA measurements for temperature domains in the vicinity of the glass transition of each phase. We show that each phase exhibits a molecular dynamic characteristic of a fragile glass liquid former. The size of the cooperative domain engaged in the relaxation processes have also been estimated and we show that this new green thermoplastic exhibits relaxation mechanisms as expected for a conventional thermoplastic, as for instance a PMMA.