Volume relaxation in amorphous and semicrystalline PET

Nano/micro electro-spun polyethylene terephthalate fibrous mat preparation and characterization

“…where, ad is PET apparent density (g/cm 3 ) = PET mat mass (g)/PET mat thickness (cm) × PET mat area (cm 2 ); and bd is bulk density of pure amorphous PET = 1.33 gr/cm 3 (Hadač et al, 2007). This measurement was performed for at least two experiments with duplicate samples.…”

Preparation and characterization of NaOH treated micro-fibrous polyethylene terephthalate nonwovens for biomedical application

“…where, ad is PET apparent density (gr/cm 3 ) = PET mat mass (gr)/ PET mat thickness (cm) × PET mat area (cm 2 ); and bd is bulk density of pure amorphous PET = 1.33 gr/cm 3 (Hadac et al, 2007). The mat thickness was measured using a digital thickness gauge (Film Master, Qualitest); with 0.001 mm resolution, designed for film thickness measurement; in millimeter and then the measured values were converted to the centimeter…”

Isobaric heating of polystyrene and evaluation of the Narayanaswamy parameter x from volume recovery data

“…The expansion of the peak area and peak shift to a higher temperature region is usually observed with increasing aging time, t a [3,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Here, a linear relationship between T p and d H can be found.…”

“…This almost discontinuous increase in V with an inflection point is followed by steady state regime at a sufficiently high temperature. The derivation of V(T) records produces rather sharp peaks in the thermal expansion coefficient, a, which is illustrated in part B and was theoretically or experimentally shown in [8][9][10][11], or even 0022-3093/$ -see front matter Ó 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.jnoncrysol.2008.…”

“…doi:10.1016/j.jnoncrysol.2008. 10.004 more commonly peaks in the specific heat capacity, c p , [3][4][5][6][7] in the case of H(T) dependences. The curve passes thought a maximum at the mentioned peak temperature, T p , and then decreases to the values characteristic of the liquid state.…”