Polylactide Blends Research Articles

Combined Effects from Dual Incorporation of ATBC as Plasticizer and Mesoporous MCM-41 as Nucleating Agent on the PLA Isothermal Crystallization in Environmentally-Friendly Ternary Composite Systems.

Different materials, based on an L-rich polylactide (PLA) as matrix, acetyl tri-n-butyl citrate (ATBC) as plasticizer, and mesoporous Mobile Crystalline Material.41 (MCM-41) particles as nucleating agent, were attained by melt extrusion. These materials are constituted by (a) binary blends of PLA and ATBC with different contents of the latest; (b) a dual compound of PLA and a given amount of MCM-41 silica (5 wt.%); and (c) ternary composites that include PLA, ATBC at several compositions and mesoporous MCM-41 at 5 wt.%. Influence of the incorporation of the plasticizer and nucleating particles has been comprehensively analyzed on the different phase transitions: glass transition, cold crystallization, melt crystallization and melting processes. Presence of both additives moves down the temperature at which PLA phase transitions take place, while allowing the PLA crystallization from the melt at 10 °C/min in the composites. This tridimensional ordering is not noticeable in the pristine PLA matrix and, accordingly, PLA crystallization rate is considerably increased under dynamic conditions and also after isothermal crystallization from either the melt or the glassy state. An important synergistic effect of dual action of ATBC and MCM-41 has been, therefore, found.

Fully Bio-Based Composites of Poly (Lactic Acid) Reinforced with Cellulose-Graft-Poly-(ε-Caprolactone) Copolymers

Due to the increasing demand for modified polylactide (PLA) meeting “double green” criteria, the research on sustainable plasticizers for PLA has attracted broad attentions. This study reported an open-ring polymerization method to fabricate cellulose (MCC)-g-PCL (poly (ε-caprolactone)) copolymers with a fully sustainable and biodegradable component. MCC-g-PCL copolymers were synthesized, characterized, and used as green plasticizers for the PLA toughening. The results indicated that the MCC-g-PCL derivatives play an important role in the compatibility, crystallization, and toughening of the PLA/MCC-g-PCL composites. The mechanical properties of the fully bio-based PLA/MCC-g-PCL composites were optimized by adding 15 wt% MCC-g-PCL, that is, the elongation at break was 22.6% (~376% higher than that of neat PLA), the tensile strength was 47.3 MPa (comparable to that of neat PLA), and the impact strength was 26 J/m (~130% higher than that of neat PLA). DSC results indicated that MCC-g-PCL reduced the Tg of the PLA blend. When the addition amount was 15 wt%, the Tg of the blend was 58.4°C. Compared with MCC, MCC-g-PCL polyester plasticizer has better thermal stability, T5% (°C) can still be maintained above 300°C. The rheological results showed that MCC-g-PCL acted as a plasticizer, the introduction of PCL flexible chain increased the mobility of PLA molecular chain, and decreased the complex viscosity, storage modulus and loss modulus of PLA blends. The MCC-g-PCL derivatives, as a new green plastic additive, have shown an interesting prospect to prepare fully bio-based composites.

Characterization of Polymer Composites between Stereocomplex Polylactide Blends with Poly (methyl methacrylate)

Polylactide stereocomplex (ST) of poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA) (PLLA:PDLA 50:50) was blended with poly(methyl methacrylate) (PMMA) 10 – 50 wt.%. The materials were dissolved in chloroform at room temperature and the films were then cast. Differential scanning calorimetry showed a stereocomplex melting peak at 208 °C – 50 °C higher than that for neat PLLA or PDLA - confirming the polylactide stereocomplex crystallites. The PMMA content ratio of 10 – 50 wt.% in the stereocomplex showed almost complete stereocomplex crystallites. A peak at about 908 cm-1 in Fourier transform infrared spectra further confirmed the stereocomplex crystallites which indicated that PMMA could blend and efficiently bond with the stereocomplex. The X-ray diffraction analysis showed that the stereocomplex crystallinity became smaller when PMMA was added. Morphology from scanning electron microscopy revealed that phases separated in the ST/PMMA blend when the amount of PMMA was increased. Adding PMMA to stereocomplex films led to an increased elongation at break which peaked at 30 % added PMMA. Increased PMMA also led to the improved thermal stability of the stereocomplex. These properties and higher toughness are also needed in common applications, in particular films for packaging and protection of manufactured products.

Bio-Based Electrospun Fibers from Chitosan Schiff Base and Polylactide and Their Cu2+ and Fe3+ Complexes: Preparation and Antibacterial and Anticancer Activities.

The Schiff base derivative (Ch-8Q) of chitosan (Ch) and 8-hydroxyquinoline-2-carboxaldehyde (8QCHO) was prepared and fibrous mats were obtained by the electrospinning of Ch-8Q/polylactide (PLA) blend solutions in trifluoroacetic acid (TFA). Complexes of the mats were prepared by immersing them in a solution of CuCl2 or FeCl3. Electron paramagnetic resonance (EPR) analysis was performed to examine the complexation of Cu2+(Fe3+) in the Ch-8Q/PLA mats complexes. The morphology of the novel materials and their surface chemical composition were studied by scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The performed microbiological screening demonstrated that in contrast to the neat PLA mats, the Ch-8Q-containing mats and their complexes were able to kill all S. aureus bacteria within 3 h of contact. These fibrous materials had efficiency in suppressing the adhesion of pathogenic bacteria S. aureus. In addition, Ch-8Q/PLA mats and their complexes exerted good anticancer efficacy in vitro against human cervical HeLa cells and human breast MCF-7 cells. The Ch-8Q-containing fibrous materials had no cytotoxicity against non-cancer BALB/c 3T3 mouse fibroblast cells. These properties render the prepared materials promising as wound dressings as well as for application in local cancer treatment.

Barrier Properties of Semicrystalline Polylactide: The Role of the Density of the Amorphous Regions

The work explains the mechanism of the improvement of oxygen barrier performance of cold-crystalized polylactide (PLA) modified with low molecular weight compounds (triethyl citrate, TEC; glycerol, Gly; and polyethylene glycol, PEG). It was found that the incorporation of small amounts of modifier (0.5–1.5 wt %) into the PLA matrix greatly reduces the oxygen transport properties. On the other hand, a further increase in the modifier content in PLA blends led to a deterioration of these properties. Based on the thermal analysis, it was shown that the modifier present in the PLA matrix did not affect the degree of crystallinity. Positron annihilation lifetime spectroscopy (PALS) and density measurements were used to correlate the observed changes in the parameters of oxygen permeability with the molecular packing in the interlamellar amorphous region. Overall, it was found that the nanostructure of the amorphous phase, largely dependent on the content and compatibility of the modifier with the polymer matrix, is of key importance in the barrier properties of PLA/modifier systems.

Biosourced Poly(lactic acid)/polyamide-11 Blends: Effect of an Elastomer on the Morphology and Mechanical Properties.

Fully biobased polylactide (PLA)/polyamide-11 (PA11) blends were prepared by melt mixing with an elastomer intermediate phase to address the low elasticity and brittleness of PLA blends. The incorporation of a biobased elastomer made of poly(butylene adipate-co-terephthalate) (PBAT) and polyethylene oxide (PEO) copolymers was found to change the rigid interface between PLA and PA11 into a much more elastic/deformable one as well as promote interfacial compatibility. The interfacial tension of the polymer pairs and spreading coefficients revealed a high tendency of PEO to spread at the PLA/PA11 interface, resulting in a complete wetting regime (interfacial tension of 0.56 mN/m). A fully percolated rubbery phase (PEO) layer at the PLA/PA11 interface with enhanced interfacial interactions and PLA chain mobility contributed to a better distribution of the stress around the dispersed phase, leading to shear yielding of the matrix. The results also show that both the morphological modification and improved compatibility upon PEO addition (up to 20 wt %) contributed to the improved elongation at break (up to 104%) and impact strength (up to 292%) of the ternary PLA/PA11/PEO blends to obtain a super-tough multiphase system.

Compatibilization of Polylactide/Poly(ethylene 2,5-furanoate) (PLA/PEF) Blends for Sustainable and Bioderived Packaging.

Despite the advantages of polylactide (PLA), its inadequate UV-shielding and gas-barrier properties undermine its wide application as a flexible packaging film for perishable items. These issues are addressed in this work by investigating the properties of melt-mixed, fully bioderived blends of polylactide (PLA) and poly(ethylene furanoate) (PEF), as a function of the PEF weight fraction (1–30 wt %) and the amount of the commercial compatibilizer/chain extender Joncryl ADR 4468 (J, 0.25–1 phr). J mitigates the immiscibility of the two polymer phases by decreasing and homogenizing the PEF domain size; for the blend containing 10 wt % of PEF, the PEF domain size drops from 0.67 ± 0.46 µm of the uncompatibilized blend to 0.26 ± 0.14 with 1 phr of J. Moreover, the increase in the complex viscosity of PLA and PLA/PEF blends with the J content evidences the effectiveness of J as a chain extender. This dual positive contribution of J is reflected in the mechanical properties of PLA/PEF blends. Whereas the uncompatibilized blend with 10 wt % of PEF shows lower mechanical performance than neat PLA, all the compatibilized blends show higher tensile strength and strain at break, while retaining their high elastic moduli. The effects of PEF on the UV- and oxygen-barrier properties of PLA are also remarkable. Adding only 1 wt % of PEF makes the blend an excellent barrier for UV rays, with the transmittance at 320 nm dropping from 52.8% of neat PLA to 0.4% of the sample with 1 wt % PEF, while keeping good transparency in the visible region. PEF is also responsible for a sensible decrease in the oxygen transmission rate, which decreases from 189 cc/m2·day for neat PLA to 144 cc/m2·day with only 1 wt % of PEF. This work emphasizes the synergistic effects of PEF and J in enhancing the thermal, mechanical, UV-shielding, and gas-barrier properties of PLA, which results in bioderived blends that are very promising for packaging applications.

Effect of the structural features of biobased linear polyester plasticizers on the crystallization of polylactides

This work presents, for the first time, a detailed report on how the nucleation and crystallization of polylactide (PLLA) are affected by biobased aliphatic polyesters plasticizers. Three biobased polyesters were synthesized via solvent-free two-stage melt polycondensation of adipic acid (AdA) with three different biobased aliphatic diols and used as plasticizers for poly (L-lactic acid) (PLLA). The molecular structure of the synthesized polyesters was proved using 1H NMR, 13C NMR and Fourier transform infrared (FTIR) spectroscopy. PLLA/AdA-based blends containing 10 wt% of the polyester plasticizers were studied by tensile tests, dynamic mechanical analysis (DMA), wide-angle x-ray scattering (WAXS), differential scanning calorimetry (DSC) and polarized light optical microscopy (PLOM). Adding the plasticizers to PLLA decreased Tg by up to 11 °C and significantly increased the elongation at break by about 8 times compared with neat PLLA. The addition of 10 wt% of any AdA-based plasticizer to PLLA increases the nucleation rate from the glassy state by around 50–110 % depending on the plasticizer. The overall crystallization rate from the glassy state was 2–3 times faster for the plasticized PLLAs than neat PLLA. These results are a consequence of the lower energy barrier for both nucleation and growth processes. The incorporation of AdA-based linear polyesters had an incremental impact on the crystal growth rate (or secondary nucleation) of PLLA spherulites from the melt and glassy states. In conclusion, the AdA-based aliphatic polyesters allowed to enhance PLLA crystallization rates and showed interesting potential for the formulation of fully biobased PLLA blends.

Modification of reactive PB‐g‐SAG core–shell particles to achieve higher toughening ability for brittle polylactide

AbstractCore–shell structured particles have been used to toughen brittle polylactide (PLA) extensively. In this research, reactive core–shell (RCS) particles with polybutadiene (PB) as core and the terpolymer styrene–acrylonitrile‐glycidyl methacrylate as shell were prepared to improve the toughening ability of RCS for PLA. The tert‐dodecyl mercaptan (TDDM) content was varied during polymerization and higher TDDM concentrations induced lower grafting and cross‐linking of the PB phase, which significantly influenced the dispersed phase morphology and toughness of RCS toughened PLA blends. With the increase of TDDM content, the phase morphology of RCS changed from uniform dispersion, net‐like structure to an agglomeration pattern. The impact strength of PLA blends increased with TDDM content and reached 922 J/m for the PLA/RCS‐T5 (TDDM: 1.18 wt%), which was 30 times higher than pristine PLA and ~3 times than PLA/RCS‐T0 blend. Higher TDDM contents decreased toughening efficiency. Appropriate TDDM contents decreased the glass transition temperature (Tg) and cross‐linking degree of RCS particles which enhanced the cavitation ability of the PB core phase and promoted the shear yielding of PLA matrix. The modification effect of TDDM solves the problem of insufficient toughening ability of core–shell particles. Under the same toughener content, the modified RCS particles make the PLA blend achieve super toughness.

Development and Characterization of Polylactide Blends with Improved Toughness by Reactive Extrusion with Lactic Acid Oligomers

In this work, we report the development and characterization of polylactide (PLA) blends with improved toughness by the addition of 10 wt.% lactic acid oligomers (OLA) and assess the feasibility of reactive extrusion (REX) and injection moulding to obtain high impact resistant injection moulded parts. To improve PLA/OLA interactions, two approaches are carried out. On the one hand, reactive extrusion of PLA/OLA with different dicumyl peroxide (DCP) concentrations is evaluated and, on the other hand, the effect of maleinized linseed oil (MLO) is studied. The effect of DCP and MLO content used in the reactive extrusion process is evaluated in terms of mechanical, thermal, dynamic mechanical, wetting and colour properties, as well as the morphology of the obtained materials. The impact strength of neat PLA (39.3 kJ/m2) was slightly improved up to 42.4 kJ/m2 with 10 wt.% OLA. Nevertheless, reactive extrusion with 0.3 phr DCP (parts by weight of DCP per 100 parts by weight of PLA–OLA base blend 90:10) led to a noticeable higher impact strength of 51.7 kJ/m2, while the reactive extrusion with 6 phr MLO gave an even higher impact strength of 59.5 kJ/m2, thus giving evidence of the feasibility of these two approaches to overcome the intrinsic brittleness of PLA. Therefore, despite MLO being able to provide the highest impact strength, reactive extrusion with DCP led to high transparency, which could be an interesting feature in food packaging, for example. In any case, these two approaches represent environmentally friendly strategies to improve PLA toughness.

Compatibilization, processing and characterization of poly(butylene adipate terephthalate)/polylactide (PBAT/PLA) blends

A blend of poly(butylene adipate terephthalate) (PBAT) and polylactide (PLA) is a combination of biodegradable materials. This study aims to prepare compatibilized PBAT/PLA in a cost-effective and timesaving way and to process the material into blown films by fine-tuning the processing parameters. First, a catalyst masterbatch is prepared by transesterification of PBAT and PLA in the presence of tetrabutyl titanate (TBT) as a catalyst. This is followed by the compounding of the two polymer types in combination with the catalyst masterbatch. Third, the compounds are processed into blown films and panels. The processing parameters for film blowing are set to reduce the anisotropy. Finally, the material properties are evaluated such as mechanical tests. The fine-tuning of parameter settings including the blow-up ratio and draw-down ratio results in a higher degree of isotropy of the blown film. By adding the catalyst masterbatch (2 wt%, which corresponds to TBT of approximately 0.002 wt% with copolymers formed) in combination with the fine-tuning of parameter settings, the samples achieved a significant improvement on the material properties. The morphology of the cryogenically fractured panel samples shows a decrease in the diameter of the dispersed phase. In the cross and machine directions, the elongation at break increased by 85 and 93%, and the trouser tear propagation resistance increased by 2.4 and 10 N mm−1, respectively. Furthermore, both the elongation at break and the trouser tear propagation of the blown films achieved a higher degree of isotropy.

Rheological properties of powder blend for extrusion of ceramic-polymer filament used in 3D printing

The article presents the results of comparative studies of the rheological properties of the ceramic polymer blend of polylactide (PLA) filled with 50 %vol alumina to evaluate the possibility of obtaining extruded filament for 3D printing.

Entirely environment-friendly polylactide composites with outstanding heat resistance and superior mechanical performance fabricated by spunbond technology: Exploring the role of nanofibrillated stereocomplex polylactide crystals

This study aims at investigating the manufacturing and characterization of all-polylactide composites prepared by melt spunbond spinning technology. To do so, a series of asymmetric stereocomplex polylactide (SC-PLA) blends (PLLA 95 wt%/PDLA 5 wt%) was melt spun. To examine the impact of molecular structure of PDLA, the blends of linear PLLA, and low and high molecular weight as well as branched PDLAs, were subjected to a single step spunbond process. DSC thermograms of the samples showed two melting temperatures at around 170 °C and 210 °C, which were attributed to the melting of homo and stereocomplex crystals, respectively. The samples were spun at 190 °C, between the homo and stereocomplex crystals' melting temperatures, and at 230 °C, above the stereocomplex crystals' melting temperature. Morphology images showed the formation of fibers in the range of 40–50 μm. Shear rheological measurements revealed that the spun SC-PLA samples had a substantially higher viscosity and storage modulus in the low frequency region, and higher shear thinning behavior, compared to the non-spun samples. Extensional rheology measurements also showed that the spun samples demonstrated strain hardening behavior. Substantial enhancement of rheological properties was noted for the samples containing the branched and high molecular weight PDLA spun at 230 °C. After etching, the spun samples at 190 °C exhibited small spherical crystals with diameters in the range of 80–90 nm, whereas comparatively thin fibers in the size range of 60–70 nm were observed for the samples spun at 230 °C. Remarkable enhancements up to 100% and 60% was noted for the tensile modulus and strength, respectively, of the spun SC-PLA samples. The spun fibers also demonstrated a considerable reduction in boiling water and hot air shrinkage. The distinctive role of nanofibrillated stereocomplex crystals as a rheology modifier and a crystallization nucleating agent makes PLA more sustainable and paves the way for the fabricated all-PLA composites in applications requiring high heat resistance and superior mechanical performance. The present study unequivocally indicates a huge potential for the sustainable entirely all-PLA products manufactured by fiber in fiber and, indeed, unfolds unknown opportunities for PLA-based merchandises in future.

(Bio)degradable biochar composites – Studies on degradation and electrostatic properties

In this work, biochar was introduced as a filler into the aliphatic-aromatic copolyester and polylactide blend. Properties and the changes during degradation of obtained materials were evaluated. A new application path was also determined by lowering the surface resistivity by increasing the biochar content. Measurements of electrostatic properties showed that surface resistivity of the poly(1,4-butylene adipate-co-1,4-butylene terephthalate)/polylactide/biochar composites is strongly dependent on the biochar content. Six-fold reduction of the surface resistivity after introduction of the 30 wt% of carbon to the reference specimen was observed. Degradation tests were conducted under abiotic and composting conditions. Visual evaluation indicated that the increase of biochar content had caused cracks to increase on the sample surfaces. The values of thermal properties after degradation do not indicated on the biochar influence on polymer matrix degradation mechanism. Nuclear magnetic resonance analysis revealed that after 42 days of hydrolytic degradation amount of polylactide was 0–2%.

Robust networks of interfacial localized graphene in cocontinuous polymer blends

Conductive polymer composites enjoy specialized applications such as electrostatic discharge protection. In this work, we create interfacially localized graphene nanoplatelets (GNPs) in a cocontinuous polymer blend of polylactide (PLA) and poly(ethylene-co-vinyl acetate) (EVA). Based on the wetting coefficient analysis, GNPs favor localization in the EVA phase. A two-step compounding sequence is designed such that a PLA/GNP masterbatch is first prepared via solution blending, and then melt compounded with the EVA. In the second step, GNPs transfer from the PLA phase to the EVA phase but become kinetically trapped at the interface, as confirmed by electron microscopy. We achieve an ultralow percolation threshold of 0.048 wt. % GNPs and obtain blends with electrical conductivities of ∼10−5 S/cm at 0.5 wt. % GNP concentration. We systematically study the shear and extensional rheology of the ternary composite system. Cocontinuous blends with interfacial GNPs exhibit higher shear and extensional viscosities compared to samples with GNPs localized entirely within the EVA phase. Rheology, in situ dielectric measurements, and transmission electron microscopic imaging after nonlinear deformations all show the interfacial GNP network undergoes structure recovery and largely remains at the PLA/EVA interface. Moreover, high electrical conductivity is maintained during 2–10 min melt compounding and conductivity recovers with annealing after nonlinear deformations. These results suggest that these robust GNP networks preserve their bulk electrical conductivity during subsequent melt processing.

Biodegradation of Ultrafine Fibrous Materials Based on Blends of Poly(hydroxybutyrate) and Polylactide

Biodegradation of Ultrafine Fibrous Materials Based on Blends of Poly(hydroxybutyrate) and Polylactide

PBAT/PLA/cellulose nanocrystals biocomposites compatibilized with polyethylene grafted maleic anhydride (PE‐g‐MA)

AbstractThe use of biodegradable polymers has grown exponentially due to their lower environmental impact when compared to conventional polymers. In this sense, biocomposites are an alternative due to their promising properties, maintaining biodegradability. For this purpose, in the present study, a biodegradable biocomposite of PBAT (poly [butylene adipate co‐terephthalate]) and PLA (polylactide) blend containing cellulose nanocrystals (CNC) were obtained, using polyethylene grafted with maleic anhydride (PE‐g‐MA) as a coupling agent. Seven formulations were produced by extrusion and had their structure, morphology, thermal, and rheological properties analyzed. The results showed a significant improvement of adhesion among the components using PE‐g‐MA as a coupling agent. Moreover, CNC and PE‐g‐MA increased the PLA crystallinity degree and reduced the complex viscosity. These results are unprecedented in the literature using these compositions and extrusion processing conditions. Therefore, these new insights provide a vast horizon for the use of biodegradable mixtures using PBAT/PLA and CNC.

The Effect of Stereocomplex Polylactide Particles on the Stereocomplexation of High Molecular Weight Polylactide Blends.

Stereocomplexation is one of several approaches for improving polylactide (PLA) properties. The high molecular weight of poly L-lactide (PLLA) and poly D-lactide (PDLA) homopolymers are a constraint during the formation of stereocomplex PLAs (s-PLAs). The presence of s-PLA particles in PLA PLLA/PDLA blends can initiate the formation of s-PLA crystalline structures. We used the solution casting method to study the utilization of s-PLA materials from high molecular weight PLLA/PDLA blends for increasing s-PLA formation. The s-PLA particles initiated the formation of high molecular weight PLLA/PDLA blends, obtaining 49.13% s-PLA and 44.34% of the total crystalline fraction. In addition, the mechanical properties were enhanced through s-PLA crystalline formation and the increasing of total crystallinity of the PLLA/PDLA blends. The s-PLA particles supported initiation for s-PLA formation and acted as a nucleating agent for PLA homopolymers. These unique characteristics of s-PLA particles show potential to overcome the molecular weight limitation for stereocomplexation of PLLA/PDLA blends.

Ring-banded spherulites in polylactide and its blends

In this paper the influence of different aspects of crystallization process on the formation of ring-banded spherulites and the transition between banded and non-banded structures in polylactide was analyzed. Based on the measurements using the differential scanning calorimetry (DSC) and polarized optical microscopy (POM), it was found that the banding phenomenon of spherulites in polylactide and its blends with triethyl citrate (TEC) exclusively depends on the degree of supercooling (ΔT). In the work, for the first time, the equilibrium melting point (Tm0) of polylactide was correlated with the isothermal crystallization temperature (Tic) in the context of banded spherulites formation. To determine the Tm0 of polylactide blends, due to the possibility of modifier migration towards the sample surface, a correction of the methodology was proposed. It has been shown that ΔT necessary to initiate the growth of spherulites with a ring pattern in polylactide ranges from 46 to 56 °C. The inclusion of TEC into polylactide matrix shifts the Tic range in which banded spherulites appear towards lower values, but does not change the required value of supercooling degree. A direct correlation between the band space of the ring-banded spherulites and the degree of supercooling was also demonstrated.

Structure and properties of in situ reactive blend of polylactide and thermoplastic starch

In this study, in situ reactive extrusion of polylactide and thermoplastic starch modified with chloropropyl trimethoxysilane coupling agent (PLA/mTPS) is proposed. The success of covalent bond formation between PLA matrix and mTPS phase is clarified by two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy with 1H1H TOCSY mode. This chemically bound PLA with starch gives the remarkable compatibility in the PLA/mTPS film, with not only a decreased glass transition temperature (47 °C) but also an increased crystallinity of PLA (Χc of 50%). It consequently increases oxygen barrier significantly and also enhances the film flexibility as observed from the drastic increase of elongation at break (from 3% to 50%). Moreover, the PLA/mTPS 60/40 (w/w) film exhibits the accelerated degradation as compared with pure PLA film.