Thermal and mechanical properties of poly(lactic acid)/starch/methylenediphenyl diisocyanate blending with triethyl citrate

Abstract

Triethyl citrate (TC) was added as a plasticizer to a blend of poly(lactic acid) (PLA) and starch in the presence of methylenediphenyl diisocyanate (MDI). As expected, TC improved the elongation at break and toughness and, at the same time, decreased the tensile strength and modulus. However, TC did not significantly affect the coupling effects of MDI on starch and PLA. The tensile strength of the blend with MDI was much greater than the tensile strength without MDI at the same TC level. The tensile properties of the blend changed dramatically as the TC concentration increased from 5 to 12.5%. At a TC concentration of 7.5%, the blend produced desirable elongation and toughness with fairly good tensile strength.

Thermal, rheological and microstructural characterisation of commercial biodegradable polyesters

“…Again, the samples studied were previously subjected to compression-moulding in a hot-plate press and further cooled down to room temperature over a period of 5 hours ("moulded" samples). reported for other bioplastics and composites containing PLA in their formulations [20][21][22][23]. On the other hand, it can be observed a small peak at about 90 ºC, before the steep increase in E' occurs.…”

Physical and mechanical properties of PLA, and their functions in widespread applications — A comprehensive review

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Influence of citric acid and water on thermoplastic wheat flour/poly(lactic acid) blends. I: Thermal, mechanical and morphological properties

“…The fluidity of TPS was also improved using citric acid. This decrease was explained by some authors by an acid hydrolysis of starch (Ke and Sun, 2003). So, co-plasticizing starch with a mixture of glycerol/citric acid is interesting because it increases starch plasticization, partial esterification can happen, and chains with lower molecular weight are obtained.…”