Toughening of poly(lactic acid) with the renewable bioplastic poly(trimethylene malonate)

Abstract

The aim of this work was to enhance poly(lactic acid)'s (PLA) flexibility and ductility by blending it with another bioplastic. Poly(trimethylene malonate) (PTM), developed as part of this study, was synthesized from 1,3-propane diol and malonic acid via melt polycondensation. Blend films of PLA and PTM were prepared by solvent casting from chloroform. Differential scanning calorimetry and thermogravimetric analysis were used to show shifted phase transitions and a single glass-transition temperature, indicating miscibility of PTM in the blend films. Morphology and mechanical characterizations of the PLA/PTM blend films were performed by atomic force microscopy using a quantitative nanomechanical property mapping mode, tensile testing, and scanning electron microscopy. Miscible blends exhibited Young's modulus and elongation at break values that can significantly extend the usefulness of PLA in commercial applications. The blending of PTM with PLA resulted in films with a 27-fold increase in toughness compared with neat PLA film.

Oligomalonate Plasticized Poly(Lactic Acid) Films: Crystallization, Thermal, and Mechanical Properties

“…DSC analysis revealed that it presents T g at −57 °C and a endothermic event associated to T m at 32 °C. The T g value is in agreement with a T g reported in the literature by Eyiler for a poly(trimethylene malonate), but no mention of T m is made. Our results suggested that this low molecular weight trimethylene malonate can present a certain X c .…”

“…We have found in the literature a previous work on blends of high molecular weight poly(trimethylene malonate) and PLA in which immiscibility was reported . In the present work we use a relatively low molecular weight oligomer based on these two bio‐based monomers.…”

“…We have found in the literature a previous work on blends of high molecular weight poly(trimethylene malonate) and PLA in which immiscibility was reported. [13] In the present work we use a relatively low molecular weight oligomer based on these two bio-based monomers. The oligomer has a higher boiling temperature avoiding vaporization during processing and better solubility in the polymer matrix due to the lower molecular weight.…”

Bio‐based plasticizer and thermoset polyesters: A green polymer chemistry approach

“…Blending polymers with low molecular weight plasticizers has been one of the most effective approaches to improve processability, flexibility, ductility, and toughness of polymers . In our previous study, the blending of PTM with poly(lactic acid) (PLA) led to significant toughness improvement and easier processing due to lower viscosity, making PLA suitable for commercial applications . In this article, we present the synthesis and characterization of a linear bio‐based polymer, poly(trimethylene malonate) (PTM) and a branched, unsaturated bio‐based polymer, poly(trimethylene itaconate) (PTI) with bimodal molecular weight distribution via melt polycondensation by following green chemistry principles.…”

Study on the poly(3‐hydroxybutyrate‐co−4‐hydroxybutyrate)‐based composites toughened by synthesized polyester polyurethane elastomer

“…With the considerably improved environmental awareness of society and concerns about the depletion of petrochemical based plastics, biodegradable plastic materials derived from renewable resources have attracted a great deal of attention. 1,2 As a typical kind of bioplastics, polyhydroxyalkanoates (PHAs) are synthesized and accumulated as intracellular carbon and energy storage material by many bacteria. 3,4 Owing to the outstanding properties, such as biodegradability, biocompatibility, excellent mechanical performance comparable with traditional petroleum-based plastics like polypropylene/(PP) and polyethylene/(PE), 5 PHAs have wide application prospects in the industrial, medical and agricultural fields.…”