Figure 4 shows the straight that allows us to calculate the activation energy ([E.sub.a]) of the acetates. The calculated activation energy for the shown exothermic events, according to the standard ASTM E698-11, were obtained using the angular coefficients values with support of Arrhenius equation .
The activation energy values we got for FeAc and FeAc-FD are smaller than those ones found in scientific literature for some transition metal acetates .
TGA/DSC curves obtained in different heating rates for acetates: (a) FeAc and (b) FeAc-FD.
synthesized the iron acetate enriched in the [sup.57]Fe isotope .
Methyl Hs of acetyl moiety substituted on to dextran appeared at 2.04-2.05 ppm in dextran acetates. The DS of acetylation (Table-1) was also calculated from 1H- NMR spectra by the comparison of the signal intensities of acetyl vs.
Thermogravimetric curves of dextran and dextran acetates 1-3 were recorded and overlay TG, DTG and 2DTG curves are shown in Figs.
Likewise, degradation of dextran acetates also started and ended later as compared to dextran.
All dextran acetates 1-3 showed approximately equal weight losses which were in the range of 78.25-78.96% in first degradation step.
Extrusion Followed by Injection Molding: The samples were extruded as described above (subsection II) and instead of collecting thermoformable extruded sheets, through proper die arrangement, the thin strands of plasticized cellulose acetate were pelletized and stored for future injection molding.
Differential scanning calorimetry (2920 Modulated DSC, TA Instruments) and thermogravimetric analysis (Hi-Res TGA 2950, TA instruments) were used for the thermal analysis of cellulose acetate plastics.
Cellulose acetate (CA), a renewable resource--based plastic, has the potential to replace polypropylene as a matrix polymer in eco-friendly bio-composite materials (15-17).
Products may also be used as external and internal lubricants, catalyst carriers, pigment dispersing agents and mold-release agents in PVC, PP, PS, PE, vinyl acetate
and PVC foam.