Change of amorphous state of poly(ethylene terephthalate) by heat treatment below the glass transition temperature

Polyesters of 2-Pyrone-4,6-Dicarboxylic Acid (PDC) Obtained from a Metabolic Intermediate of Lignin

“…The reported onset T g value of PET [= P(PDCB) 0:0 ] was 61 C, 23 consistent with the present observation. The T g values increased as an increase in x, and it reached 103…”

The effect of chain structure on the annealing and deformation behaviour of polymers

“…The occurrence of a redistribution of rotational isomers daring annealing below Tg has also been reported by Ito et al (82) with Polyethyleneterephthalate (P.E.T.). Observing a bond at 973-5 cm -* ascribed to a trans configuration in the chain, they measured a reduction in this absorption due to annealing.…”

An overview of the nonequilibrium behavior of polymer glasses

“…Thus, since the excess enthalpy decreases during annealing, the enthalpy recovered during heating increases with increasing annealing time, and the endothermic peaks become correspondingly larger. This is depicted ,1 19 in Figure 12, where the DSC scans were performed on amorphous PET annealed for various times at 23 0 C.…”