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. 2021 Jul 23;13(15):2429.
doi: 10.3390/polym13152429.

Reaction Mechanism and Mechanical Property Improvement of Poly(Lactic Acid) Reactive Blending with Epoxy Resin

Krittameth Kiatiporntipthak  1 , Nanthicha Thajai  2 , Thidarat Kanthiya  1 , Pornchai Rachtanapun  1   3   4 , Noppol Leksawasdi  1   3   4 , Yuthana Phimolsiripol  1   3   4 , David Rohindra  5 , Warintorn Ruksiriwanich  4   6 , Sarana Rose Sommano  4   7 , Kittisak Jantanasakulwong  1   3   4
Affiliations

Reaction Mechanism and Mechanical Property Improvement of Poly(Lactic Acid) Reactive Blending with Epoxy Resin

Krittameth Kiatiporntipthak et al. Polymers (Basel). .

Abstract

Polylactic acid (PLA) was melt-blended with epoxy resin to study the effects of the reaction on the mechanical and thermal properties of the PLA. The addition of 0.5% (wt/wt) epoxy to PLA increased the maximum tensile strength of PLA (57.5 MPa) to 67 MPa, whereas the 20% epoxy improved the elongation at break to 12%, due to crosslinking caused by the epoxy reaction. The morphology of the PLA/epoxy blends showed epoxy nanoparticle dispersion in the PLA matrix that presented a smooth fracture surface with a high epoxy content. The glass transition temperature of PLA decreased with an increasing epoxy content owing to the partial miscibility between PLA and the epoxy resin. The Vicat softening temperature of the PLA was 59 °C and increased to 64.6 °C for 0.5% epoxy. NMR confirmed the reaction between the -COOH groups of PLA and the epoxy groups of the epoxy resin. This reaction, and partial miscibility of the PLA/epoxy blend, improved the interfacial crosslinking, morphology, thermal properties, and mechanical properties of the blends.

Keywords: interfacial crosslink; reaction; thermal properties; toughness.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Tensile properties of PLA blend with 0–20% epoxy (a) Stress–strain curve, and (b) Maximum tensile strength and elongation at break. The different of each lowercase and each uppercase letters indicate the mean values of the elongation at break and the maximum tensile strength differ significantly (p < 0.05), respectively.
Figure 2
Figure 2
SEM fracture surface images of (a) PLA/epoxy0.5, (b) PLA/epoxy1, (c) PLA/Epoxy2, (d) PLA/epoxy5, (e) PLA/Epoxy10, and (f) PLA/Epoxy20.
Figure 3
Figure 3
The second scan DSC curves of epoxy, PLA, and the PLA blend with 0.5–20% epoxy.
Figure 4
Figure 4
The Vicat softening temperature of PLA and the PLA blend with 0.5–20% epoxy. The mean values indicate by the different lowercase letters differ significantly (p < 0.05).
Figure 5
Figure 5
13C NMR spectra and structures of (a) neat PLA, (b) epoxy, and (c) the PLA/epoxy20 blend.
Figure 6
Figure 6
1H NMR spectra and structures of (a) neat PLA, (b) epoxy, and (c) the PLA/epoxy20 blend.
See this image and copyright information in PMC

References

    1. Gregor-Svetec D., Leskovšek M., Leskovar B., Elesini U.S., Leskovar B., Elesini U.S., Vrabič-Brodnjak U. Analysis of PLA composite filaments reinforced with lignin and polymerised-lignin-treated NFC. Polymers. 2021;13:2174. doi: 10.3390/polym13132174. - DOI - PMC - PubMed
    1. Jantanasakulwong K., Rohindra D., Mori K., Kuboyama K., Ougizawa T. Thermoplastic elastomer by reactive blending of poly(butylene succinate) with ethylene-propylene-diene terpolymer and ethylene-1-butene rubbers. J. Elastomers Plast. 2015;47:215–231. doi: 10.1177/0095244313507805. - DOI
    1. Jumaidin R., Diah N.A., IIyas R.A., Alamjuri R.H., Yusof F.A.M. Processing and characterization of banana leaf fibre reinforced thermoplastic cassava starch composites. Polymers. 2021;13:1420. doi: 10.3390/polym13091420. - DOI - PMC - PubMed
    1. Malyszek Z., Lewandowicz J., Thanh-Blicharz J.L., Walkowiak K., Kowalczewski P.L., Baranowska H.M. Water behavior of emulsions stabilized by modified potato starch. Polymers. 2021;13:2200. doi: 10.3390/polym13132200. - DOI - PMC - PubMed
    1. Surin S., You S., Seesuriyachan P., Muangrat R., Wangtueai S., Jambrak A.R., Phongthai S., Jantanasakulwong K., Chaiyaso T., Phimolsiripol Y. Optimization of ultrasonic-assisted extraction of polysaccharides from purple glutinous rice bran (Oryza sativa L.) and their antioxidant activities. Sci. Rep. 2020;10:10410. doi: 10.1038/s41598-020-67266-1. - DOI - PMC - PubMed

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