Effect of Coupling Agent on the Dispersion of PETG Montmorillonite Nanocomposite films.

Abstract

Polyethylene terephthalate glycol (PETG) is a clear amorphous polymer, which is extensively used in flexible packaging. The dual packaging requirements of recyclability and long-term shelf life are often difficult to achieve. Meeting these needs become more urgent when considering food packaging for large volumes of soldiers positioned in different parts of the world. Our approach is to develop a high barrier PET packaging system via the Montmorillonite layered silicate (MLS) based nano technology. Prior research has indicated the significant impact of the polymer crystalline regions on the properties of the resultant nanocomposite. Therefore we must first investigate the amorphous PETG. We must also investigate the influence of increased matrix polarity on dispersion of the PETG by incorporating maleic anhydride (MA) onto the PETG backbone. The influence of the clay concentration and maleation are independently investigated. The glass transition of the as-processed and annealed samples are analyzed using Differential Scanning Calorimetry (DSC) while the thermal stability is determined using Thermogravimetric Analysis (TGA). Testing showed a slight depression in the glass transition temperature of PETG film when the MLS is introduced into the system. The nanocomposite films also demonstrated a lower thermal stability in relation to the neat PETG films. The barrier properties were determined on an in-house built calibration unit based on atomic mobility under high vacuum. X-ray diffraction and TEM were utilized to determine the dispersion of the MLS in PETG. The results indicate that the dispersion was concentration independent but maleation of the PETG led to a slight decrease in agglomeration. An increased ultimate tensile strength and modulus was observed in PETG nanocomposites. The barrier properties were improved by incorporating the MLS into the system. Maleation of the PETG resulted in significant yellowing of the nanocomposites.

Preparation and characterization of tapioca starch‐poly(lactic acid)‐Cloisite NA+ nanocomposite foams

“…The first diffraction peaks (001) d-spacings for both of these intercalated nanocomposites were narrow, indicating a strong intercalated behavior and a high stacking order of the successive clay layers in the nanocomposites. Similar occurrences were observed by Kumar et al [26] and Ranade et al [27] The higher clay content of 7 wt % tended to have the same diffraction profile, with a slightly higher first diffraction peak (001) d-spacing angle at 2θ = 3.86°. However, the broader peak indicated some level of reduction in the clay platelets per stack in the polymer matrix.…”

Preparation and characterization of tapioca starch–poly(lactic acid) nanocomposite foams by melt intercalation based on clay type

“…The decrease in T g with the addition of organoclays 25A and 15A could have been due to their plasticizing effects on the TS/PLA chains. Ranade et al (2004) reported similar results in their work. Figure 10 shows typical DSC thermographs of the first heating scans with the distinct endothermic peaks (T m ) of the foams.…”

“…The first diffraction peak (0 0 1) d-spacing for the intercalated nanocomposite was narrow, indicating a strong intercalated behavior and a high stacking order of the successive clay layers in the nanocomposites. Similar occurrence also was observed by Kumar et al (2003) and Ranade et al (2004). The second diffraction peak occurred at 2θ = 5.16°, appeared smaller and weaker, and was due to the second registry (0 0 2) d-spacing of the organoclay (Ray et al, 2002;Pluta, 2004).…”

Structure and Mechanical Properties of Nanocomposites Based on an Amorphous Copolyester

“…[33] A methyl tallow bis(2-hydroxyethyl) ammonium organic modification led to better dispersion than octadecylamine or dodecylamine modifications. [34] In the case of 1,4-cyclohexanedimethanol-terephthalic acid-ethylene glycol copolymer (PETG), the effects of the organoclay presence on the viscoelastic properties [35] and on the properties of its films [36,37] were studied. However, to our knowledge, no work has been published based on PCTG, which is a copolymer with the same components as those of PETG, but with different proportions of the chemical groups.…”