Molecular dynamics of copolyester/clay nanocomposites as investigated by viscoelastic and dielectric analysis

Abstract

We have investigated the molecular dynamics of poly(ethylene glycol-cocycloxeane-1,4-dimethanol terephthalate) (PETG) nanocomposites based on a organically modified layered silicate. Intercalated nanocomposites were prepared by melt compounding technique as evidenced from the X-ray diffraction and transmission electron microscopy studies. Two relaxation processes were observed in pure PETG as well as in the nanocomposites. The low-temperature b-process was assigned to the local motions of C¼ ¼O polar groups and the a-process was due to the glass-rubber transition or the segmental relaxations associated with the polymer chain backbone. Presence of layered silicates accelerated a-relaxation dynamics in the nanocomposites accompanied by a depression in T g which was attributed to the reduced intermolecular cooperativity between intercalated polymers chains. Additionally, a direct comparison between the viscoelastic and dielectric studies shows excellent agreement between the accelerated a dynamics of the nanocomposites.

Nanoclay reinforced bio-based elastomers: Synthesis and characterization

“…This confirms the theoretical calculation. The miscibility of Cloisite Ò 30B and poly(AOME) may be due to the formation of hydrogen bonding between the hydroxyl groups in Cloisite Ò 30B and carbonyls in poly(AOME) [64].…”

Effects of the processing temperature on the nanostructure and mechanical properties of PCTG‐based nanocomposites

“…However, the intensity of the tan δ peaks of the NCs increased, and the peaks widened after processing at high temperatures. This indicates28 interaction between the polymer matrix and the clay layers resulting in the reduction of internal friction and the immobilization of the polymer chains. Thus, while some surfactant migration occurred, it must have been too small to influence viscosity because the T g hardly changed.…”

Processing and Performance of Polymeric Transparent Conductive Composites

“…The DC conductivity values ( DC ) have been obtained through the AC conductivity measurement [85][86][87] as shown by AC ( ) = 0 ( ) = DC + , (A.8)…”