In the first step, MTPS was directly prepared from regular silver medal pearl cornstarch and 2.
In this study, MTPS was chemically modified with 2.
When MTPS was used, the resulting PBAT/TPS melt-blend (70/30 wt%) was completely extracted out (entry 2, Table 1).
1] was also observed in the graft copolymer but not in the MTPS precursor.
The tensile properties were studied from the PBAT-g-MTPS graft copolymers containing 70 wt% polyester, which had been prepared from MTPS modified with different MA contents, i.
In contrast to TPS, the lower molecular weight for MTPS (39) together with its increased reactivity led, by melt blending with PBAT, to the formation of stronger covalent linkages between partners, a more complete homogenization, and therefore finer phase morphology for the resulting MTPS-PBAT melt-blends.
Such a behavior could be explained by the enhanced reactivity for MTPS, increasing the number of covalent (ester) bonds between the MTPS and PBAT phases.
In addition to the grafting reactions taking place between the PBAT and MTPS phases, reduction of molecular weight for MTPS yielded a finer morphology of the dispersed phase (MTPS) in the continuous PBAT matrix, together with a concomitant increased interfacial area necessary for efficient grafting reactions.
WAXS diffractograms of regular cornstarch, TPS, the direct PBAT/TPS melt-blend prepared without MA, MTPS (modified with 2.
Since the MTPS had a lower molecular weight, the energy input in the extruder was sufficient to destructurize the native crystals completely.
It is worth nothing that the melting temperature of MTPS was not detected in the graft copolymer (39), again supporting the good homogenization of MTPS within the polyester matrix.