A comparative study on the effect of different reactive compatibilizers on injection-molded pieces of bio-based high-density polyethylene/polylactide blends

This is the peer reviewed version of the following article: Quiles-Carrillo, L., Montanes, N., Jorda-Vilaplana, A., Balart, R. and Torres-Giner, S. (2019), A comparative study on the effect of different reactive compatibilizers on injection-molded pieces of bio-based high-density polyethylene/polylactide blends. J. Appl. Polym. Sci., 136, 47396, which has been published in final form at https://doi.org/10.1002/APP.47396. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] The present study reports on the development of binary blends consisting of bio-based high-density polyethylene (bio-HDPE) with polylactide (PLA), in the 5¿20 wt % range, prepared by melt compounding and then shaped into pieces by injection molding. In order to enhance the miscibility between the green polyolefin and the biopolyester, different reactive compatibilizers were added during the melt-blending process, namely polyethylene grafted maleic anhydride (PE-g-MA), poly(ethylene-co-glycidyl methacrylate) (PE-co-GMA), maleinized linseed oil (MLO), and a combination of MLO with dicumyl peroxide (DCP). Among the tested compatibilizers, the dual addition of MLO and DCP provided the binary blend pieces with the most balanced mechanical performance in terms of rigidity and impact strength as well as the highest thermal stability. The fracture surface of the binary blend piece processed with MLO and DCP revealed the formation of a continuous structure in which the dispersed PLA phase was nearly no discerned in the bio-HDPE matrix. The resultant miscibility improvement was ascribed to both the high solubility and plasticizing effect of MLO on the PLA phase as well as the crosslinking effect of DCP on both biopolymers. The latter effect was particularly related to the formation of macroradicals of each biopolymer that, thereafter, led to the in situ formation of bio HDPE-co-PLA copolymers and also to the development of a partially crosslinked network in the binary blend. As a result, cost-effective and fully bio-based polymer pieces with improved mechanical strength, high toughness, and enhanced thermal resistance were obtained.This research was funded by the EU H2020 project YPACK (reference number 773872) and by the Ministry of Science, Innovation, and Universities (MICIU, project numbers MAT2017-84909-C2-2-R and AGL2015-63855-C2-1-R). Quiles-Carrillo and Torres-Giner are recipients of a FPU grant (FPU15/03812) from the Spanish Ministry of Education, Culture, and Sports (MECD) and a Juan de la Cierva contract (IJCI-2016-29675) from the MICIU, respectively.Quiles-Carrillo, L.; Montanes, N.; Jorda-Vilaplana, A.; Balart, R.; Torres-Giner, S. (2019). 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Determination of Interleukin-6 and Tumor Necrosis Factor-alpha concentrations in Iranian-Khorasanian patients with preeclampsia

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Statistical Multiplicity in Systematic Reviews of Anaesthesia Interventions: A Quantification and Comparison between Cochrane and Non-Cochrane Reviews

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Dynamic modeling and simulation of an integral bipropellant propulsion double-valve combined test system

This work was financially supported by the National Natural Science Foundation of China (No. 11101023) and the China Scholarship Council (No. 201203070237)