Loss of thermoplastic elastomer toughening in polylactide after weathering

Meyva‐Zeybek, Yelda; Kaynak, Cevdet

doi:10.1002/app.47177

Cited by 5 publications

(5 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sample was heated again from 30 to 200 °C at the same increase rate. The second heating curve was recorded, and the crystallinity of PLA was calculated as [ 16 ]

where X c represents the crystallinity of PLA,

and

are the melting enthalpy and cold crystallization enthalpies of the sample, respectively, and

and

are the melting enthalpy and PLA mass fraction of 100% crystallized PLA, respectively.…”

Section: Methodsmentioning

confidence: 99%

High-Toughness Poly(lactic Acid)/Starch Blends Prepared through Reactive Blending Plasticization and Compatibilization

Hu¹,

Ao²,

Zhang³

et al. 2020

Molecules

View full text Add to dashboard Cite

In this study, poly(lactic acid) (PLA)/starch blends were prepared through reactive melt blending by using PLA and starch as raw materials and vegetable oil polyols, polyethylene glycol (PEG), and citric acid (CA) as additives. The effects of CA and PEG on the toughness of PLA/starch blends were analyzed using a mechanical performance test, scanning electron microscope analysis, differential scanning calorimetry, Fourier-transform infrared spectroscopy, X-ray diffraction, rheological analysis, and hydrophilicity test. Results showed that the elongation at break and impact strength of the PLA/premixed starch (PSt)/PEG/CA blend were 140.51% and 3.56 kJ·m−2, which were 13.4 and 1.8 times higher than those of pure PLA, respectively. The essence of the improvement in the toughness of the PLA/PSt/PEG/CA blend was the esterification reaction among CA, PEG, and starch. During the melt-blending process, the CA with abundant carboxyl groups reacted in the amorphous region of the starch. The shape and crystal form of the starch did not change, but the surface activity of the starch improved and consequently increased the adhesion between starch and PLA. As a plasticizer for PLA and starch, PEG effectively enhanced the mobility of the molecular chains. After PEG was dispersed, it participated in the esterification reaction of CA and starch at the interface and formed a branched/crosslinked copolymer that was embedded in the interface of PLA and starch. This copolymer further improved the compatibility of the PLA/starch blends. PEGs with small molecules and CA were used as compatibilizers to reduce the effect on PLA biodegradability. The esterification reaction on the starch surface improved the compatibilization and toughness of the PLA/starch blend materials and broadens their application prospects in the fields of medicine and high-fill packaging.

show abstract

“…The sample was heated again from 30 to 200 °C at the same increase rate. The second heating curve was recorded, and the crystallinity of PLA was calculated as [ 16 ]

where X c represents the crystallinity of PLA,

and

are the melting enthalpy and cold crystallization enthalpies of the sample, respectively, and

and

are the melting enthalpy and PLA mass fraction of 100% crystallized PLA, respectively.…”

Section: Methodsmentioning

confidence: 99%

High-Toughness Poly(lactic Acid)/Starch Blends Prepared through Reactive Blending Plasticization and Compatibilization

Hu¹,

Ao²,

Zhang³

et al. 2020

Molecules

View full text Add to dashboard Cite

show abstract

“…Recently, with in situ fibrillation of TPU in PLA/TPU blends, improvements in the toughness of printed structures were reported due to the generation of TPU fibrils, enhanced PLA crystallization around the fibrillated structures, and hence improved interfacial interactions [45] Considering the long-term behavior of PLA/TPU blends, it has been reported that weathering could cause drastic losses in the strength and toughness of the blends. [46] It is still not very clear in the literature how changes in the TPU molecular structure such as variations in HS content or in the molecular weight of SS could influence the final properties of PLA/TPU blend systems. Therefore, in this study we aimed at exploring how the variations in the HS content of TPUs could influence the morphological, rheological, and mechanical properties of PLA/TPU blends without using any compatibilizer and with using only 15 wt% TPU.…”

Section: Introductionmentioning

confidence: 99%

Effect of TPU hard segment content on the rheological and mechanical properties of PLA/TPU blends

Nofar

Mohammadi

Carreau

2020

J of Applied Polymer Sci

View full text Add to dashboard Cite

Blends of an amorphous polylactide (PLA) with three different thermoplastic polyurethane (TPU) grades having various hard segment (HS) contents are prepared at the blending ratio of 85/15 wt% through a twin‐screw extruder (TSE) at processing temperatures of 150 and 190°C. Blends of a semicrystalline PLA with 15 wt% of the noted TPU grades are also processed in the TSE at 190°C to investigate the matrix crystallization effect on the morphology and property enhancements. The rheological experiments reveal that the increase in TPU HS content significantly increases the phase compatibility between PLA and TPU as also suggested by the finer morphology of the TPU phase, although the use of lower HS TPUs is more favorable to enhance the ductility and impact properties of the blends.

show abstract

“…The levels of the processing parameters in Table 1 were chosen to obtain adequate values for the production of electrospun nanofibers, in accordance with previous works that utilized PCL as an electrospinning material. [30][31][32] Furthermore, the optimal processing condition resulted in maximal C R . Therefore, the larger-the-better characteristic was applied to the analysis to find the optimal processing parameters that made C R → 100.…”

Section: Effects Of Electrospinning Processing Parameters On C Rmentioning

confidence: 99%

Investigation of Effects of Electrospinning Parameters on Transcription Quality of Nanofibrous Bifurcated‐Tubular Scaffold

Eom

Kim

2022

Macro Materials & Eng

View full text Add to dashboard Cite

A parametric sensitivity study to improve the transcription quality of the nanofibrous bifurcated-tubular scaffold is performed to resolve the limited transcription quality issue in fabricating the scaffold based on hydrogel-assisted electrospinning (GelES). To characterize the transcription quality of the fabricated 3D nanofibrous bifurcated-tubular scaffold structure, two different measures of a coverage ratio (C R ) and a corner profile fidelity (F C ) are evaluated. Results of sensitivity analysis on C R , in which the design of experiments is based on the Taguchi method, revealed that the C R increases with decreasing tip-to-collector distance (TCD) and polycaprolactone concentration (C PCL ). Moreover, among the processing parameters, namely, TCD, C PCL , and applied voltage (V A ), the TCD is found to be the dominantly affecting processing parameter. Parametric study results show that F C increases with the branching angle (𝜽 B ). By combining the optimal processing condition and a maximum 𝜽 B of 120°, a leakage-free 3D nanofibrous bifurcated-tubular scaffold with a sharp carina is fabricated by the GelES.

show abstract

Loss of thermoplastic elastomer toughening in polylactide after weathering

Cited by 5 publications

References 39 publications

High-Toughness Poly(lactic Acid)/Starch Blends Prepared through Reactive Blending Plasticization and Compatibilization

High-Toughness Poly(lactic Acid)/Starch Blends Prepared through Reactive Blending Plasticization and Compatibilization

Effect of TPU hard segment content on the rheological and mechanical properties of PLA/TPU blends

Investigation of Effects of Electrospinning Parameters on Transcription Quality of Nanofibrous Bifurcated‐Tubular Scaffold

Contact Info

Product

Resources

About