Poly(lactic acid) (PLA) is characterised by its inherent brittleness, a detrimental feature for the production of durable bioplastics. PLA has been toughened by a low amount (12 wt-%) of various thermoplastic elastomers (TPE) including poly(ether-b-ester) (PEEs), poly(ether-b-amide) (PEBA) and poly(ether-b-urethane) (PEU). PLA–TPE blends were prepared by using a twin screw extruder. Ductility and impact resistance can be slightly improved with the incorporation of TPEs but but PEBA appears the most efficient. Reactive compatibilisation has been performed with the addition in the melt of a low amount (2 wt-%) of 4,4-methylene diphenyl diisocyanate. All compatibilised blends exhibit high toughness with similar ductility. These blends preserve good stiffness and high tensile strength. Compatibilised PEBA blends can be considered as super tough poly(lactic acid) materials. This work confirms that the flexibility of the elastomer together with the quality of the interfacial adhesion between the rigid (PLA) and the soft (TPE) phases are the primary factors influencing the toughness.
KrishnanS, PandeyP, MohantyS, Toughening of polylactic acid: an overview of research progress. Polym Plast Tech Eng. 2016;55(15):1623–1652. doi: 10.1080/03602559.2015.1098698
2.
NagarajanV, MohantyAK, MisraM.Perspective on polylactic acid (PLA) based sustainable materials for durable applications: focus on toughness and heat resistance. ACS Sustain Chem Eng. 2016;4(6):2899–2916. doi: 10.1021/acssuschemeng.6b00321
3.
VachonA, PépinK, BélandO, Thermal, mechanical and morphological properties of binary and ternary PLA blends containing a poly(ether ester) elastomer. J Biobased Mater Bio. 2015;9(2):205–217. doi: 10.1166/jbmb.2015.1507
4.
NagarajanV, MohantyAK, MisraM.Blends of polylactic acid with thermoplastic copolyester elastomer: effect of functionalized terpolymer type on reactive toughening. Polym Eng Sci. 2017. doi 10.1002/pen.24566.
VachonA, PépinK, BalampanisE, Compatibilization of PLA/PEBA blends via reactive extrusion: a comparison of different coupling agents. J Polym Environ. 2017;25(3):812–827. doi: 10.1007/s10924-016-0860-x
7.
JauzeinT, HuneaultMA, HeuzeyMC.Crystallinity and mechanical properties of polylactide/ether–amide copolymer blends. J App Polym Sci. 2017;134(14):338. doi:10.1002/app.44677.
8.
LiY, ShimizuH.Toughening of polylactide by melt blending with a biodegradable poly(ether)urethane elastomer. Macromol Biosci. 2007;7(7):921–928. doi: 10.1002/mabi.200700027
9.
ZengJB, LiYD, HeYS, Improving flexibility of poly(l-lactide) by blending with poly(l-lactic acid) based poly(ester–urethane): morphology, mechanical properties, and crystallization behaviors. Ind Eng Chem Res. 2011;50(10):6124–6131. doi: 10.1021/ie102422q
10.
DoganSK, ReyesEA, RastogiS, Reactive compatibilization of PLA/TPU blends with a diisocyanate. J App Polym Sci. 2014;131(10):40251–40260. doi: 10.1002/app.40251
11.
OliaeiE, KaffashiB, DavoodiS.Investigation of structure and mechanical properties of toughened poly(l-lactide)/thermoplastic poly(ester urethane) blends. J App Polym Sci. 2016;133(15):43104–43116. doi: 10.1002/app.43104
ImreB, BedoD, DomjánA, Structure, properties and interfacial interactions in poly(lactic acid)/polyurethane blends prepared by reactive processing. Eur Polym J. 2013;49(10):3104–3113. doi: 10.1016/j.eurpolymj.2013.07.007
16.
LuX, WeiX, HuangJ, Supertoughened poly(lactic acid)/polyurethane blend material by in situ reactive interfacial compatibilization via dynamic vulcanization. Ind Eng Chem Res. 2014;53(44):17386–17393. doi: 10.1021/ie503092w
17.
XuY, LoiJ, DelgadoP, Reactive compatibilization of polylactide/polypropylene blends. Ind Eng Chem Res. 2015;54(23):6108–6114. doi: 10.1021/acs.iecr.5b00882
18.
JanorkarAV, FritzEWJr, BurgKJL, Grafting amine-terminated branched architectures from poly(l-lactide) film surfaces for improved cell attachment. J Biomed Materials Res B. 2007;81B(1):142–152. doi: 10.1002/jbm.b.30647
19.
Al-ItryR, LamnawarK, MaazouzA.Reactive extrusion of PLA, PBAT with a multi-functional epoxide: physico-chemical and rheological properties. Eur Polym J. 2014;58:90–102. doi: 10.1016/j.eurpolymj.2014.06.013
20.
YangQ, HirataM, HsuYI, Improved thermal and mechanical properties of poly(butylene succinate) by polymer blending with a thermotropic liquid crystalline polyester. J App Polym Sci. 2014;131(4):39952–39959.
21.
DongW, ZouB, YanY, Effect of chain-extenders on the properties and hydrolytic degradation behavior of the poly(lactide)/ poly(butylene adipate-co-terephthalate) blends. Int J Mol Sci. 2013;14(10):20189–20203. doi: 10.3390/ijms141020189
22.
KeT, SunXS.Thermal and mechanical properties of poly(lactic acid)/starch/methylenediphenyl diisocyanate blending with triethyl citrate. J App Polym Sci. 2003;88(13):2947–2955. doi: 10.1002/app.12112
23.
KimMW, HongSM, LeeD, Chain extension effects of para-phenylene diisocyanate on crystallization behavior and biodegradability of poly(lactic acid)/poly(butylene terephthalate) blends. Adv Compos Mater. 2010;19(4):331–348. doi: 10.1163/092430409X12605406698471
24.
ShenT, LuM, LiangL.Modification of the properties of polylactide/polycaprolactone blends by incorporation of blocked polyisocyanates. J Macromol Sci Pure App Chem. 2013;50(5):547–554. doi: 10.1080/10601325.2013.781463
25.
ShenT, LuM, ZhouD, Effect of reactive blocked polyisocyanate on the properties of solvent cast blends from poly(lactic acid) and poly(ethylene glycol). J App Polym Sci. 2012;125(3):2071–2077. doi: 10.1002/app.36276
YangJ, NieS, ZhuJ.A comparative study on different rubbery modifiers: effect on morphologies, mechanical, and thermal properties of PLA blends. J App Polym Sci. 2016;133(17). 10.1002/app.43340.
28.
ShethJP, XuJ, WilkesGL.Solid state structure-property behavior of semicrystalline poly(ether-block-amide) PEBAX® thermoplastic elastomers. Polymer. 2003;44(3):743–756. doi: 10.1016/S0032-3861(02)00798-X
29.
FisherEW, SterzelHJ, WegnerG.Kolloid Z Z Polym. 1973;251:981–990.
30.
HongH, WeiJ, YuanY, A novel composite coupled hardness with flexibleness-polylactic acid toughen with thermoplastic polyurethane. J App Polym Sci. 2011;121(2):855–861. doi: 10.1002/app.33675
31.
FengF, YeL.Morphologies and mechanical properties of polylactide/thermoplastic polyurethane elastomer blends. J App Polym Sci. 2011;119(5):2778–2783. doi: 10.1002/app.32863
32.
MartinO, AvérousL.Poly(lactic acid): plasticization and properties of biodegradable multiphase systems. Polymer (Guildf). 2001;42(14):6209–6219. doi: 10.1016/S0032-3861(01)00086-6
33.
JacobsenS, FritzHG.Plasticizing polylactide – the effect of different plasticizers on the mechanical properties. Polym Eng Sci. 1999;39(7):1303–1310. doi: 10.1002/pen.11517
BaiardoM, FrisoniG, ScandolaM, Thermal and mechanical properties of plasticized poly(l-lactic acid). J App Polym Sci. 2003;90(7):1731–1738. doi: 10.1002/app.12549
36.
PiorkowskaE, KulinskiZ, GaleskiA, Plasticization of semicrystalline poly(l-lactide) with poly(propylene glycol). Polymer (Guildf). 2006;47(20):7178–7188. doi: 10.1016/j.polymer.2006.03.115
37.
AndrusyszynPM, SunkaraHB.Methods for improving physical properties of polyesters. United States Patent US 0105665 A1. 2011.
38.
JunCL.Reactive blending of biodegradable polymers: PLA and starch. J Polym Env. 2000;8(1):33–37. doi: 10.1023/A:1010172112118
39.
YuF, LiuT, ZhaoX, Effects of talc on the mechanical and thermal properties of polylactide. J App Polym Sci. 2012;125(suppl. 2):E99–E109. doi: 10.1002/app.36260
40.
HanL, HanC, DongL.Morphology and properties of the biosourced poly(lactic acid)/poly(ethylene oxide-b-amide-12) blends. Polym Compos. 2013;34(1):122–130. doi: 10.1002/pc.22383
