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Biodegradable polymer nanocomposites have received great attention due to their synergistic properties of good mechanical and barrier properties; yet, they are biodegradable. In this research, prior to compression into thin sheets, polylactic acid (PLA), tapioca starch, glycerol and maleic anhydride (MA) were compounded with different loadings of montmorillonite (MMT) through a twin screw extruder. MMT was added to improve the mechanical and barrier properties of PLA/starch blend. The effects of MMT loadings on tensile property, morphology and biodegradability were studied. X-Ray diffraction analysis showed that samples with MMT loadings below 6 phr exhibited exfoliated structure, while samples that contained MMT above 6 phr (5.66 wt%) exhibited intercalated structure. The exfoliated-type structure was observed using transmission electron microscopy. These effects were manifested in the tensile results, which showed an increase in modulus, tensile strength and elongation at break. However, for the modulus, the MMT content was limited to 4 phr (3.85 wt%). Beyond that, the modulus decreased. It was thought that above 4 phr, the MMT particles agglomerated, thus reducing the modulus of the samples. This argument was supported by field emission scanning electron microscopic images, which showed big lump when MMT loadings were at 6 and 8 phr (7.41 wt%). Meanwhile, the addition of MMT has improved the water barrier property and hastened the rate of biodegradation. The nanosized MMT particles disturb the continuity of PLA/starch chain, which formed pathways for microorganisms to enter and attack the chain, thus increasing the biodegradation rate. The particle is also able to block a tortuous pathway for water to enter the starch chain, thus reducing the water uptake and improving the physical barrier of nanocomposite.

Thermoplastic starch, polylactic acid glycerol and maleic anhydride (MA) were compounded with natural montmorillonite (MMT) through a twin screw extruder to investigate the effects of different loading of MMT on tensile properties and thermal behavior of the nanocomposites. Tensile results showed an increased in modulus, tensile strength and elongation at break. However, beyond 3phr of MMT the modulus of samples decreased because the MMT particles agglomerated. The thermal properties were characterized by using differential scanning calorimeter (DSC). The results showed that MMT increased melting temperature and crystallization temperature of matrix but reduction in glass transition temperature was observed.

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Supramolecular elastomers were synthesized using vegetable oil materials namely palm acid oil (PAO) and sunflower oil (SFO). The oils were first epoxidized using formic acid and hydrogen peroxide. The epoxidized oils and adipic acid were then reacted to make polyacids, mainly triacid. Finally, diethylenetriamine (DETA) was added to polyacid to yield fatty amide and a polycondensation with urea performed to achieve the desired elastomers. The synthesized materials were characterized by using Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (NMR) and Thermogravimetric Analyzer (TGA) in order to determine structure, type of bonding and thermal stability. The spectrums revealed that the synthesized fatty amides are contained amide groups that correctly formed from reaction of amine groups of DETA and acid functionality of polyacids. Moreover, the resulted structures showed the formation of multiple hydrogen-bonding in the elastomers. TGA thermograms clearly indicated good thermal stability of the elastomers to 500 °C.