{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,28]],"date-time":"2025-11-28T12:28:26Z","timestamp":1764332906996,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,5,22]],"date-time":"2020-05-22T00:00:00Z","timestamp":1590105600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["SFRH\/BPD\/121526\/2016","SFRH\/BD\/145345\/2019","POCI-01-0145-FEDER-007265","PTDC\/BTM-MAT\/28237\/2017","PTDC\/EMD-EMD\/28159\/2017","UID\/QUI\/50006\/2020","UID\/FIS\/04650\/2020","PEST-C\/QUI\/UIO686\/2019"],"award-info":[{"award-number":["SFRH\/BPD\/121526\/2016","SFRH\/BD\/145345\/2019","POCI-01-0145-FEDER-007265","PTDC\/BTM-MAT\/28237\/2017","PTDC\/EMD-EMD\/28159\/2017","UID\/QUI\/50006\/2020","UID\/FIS\/04650\/2020","PEST-C\/QUI\/UIO686\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>This work reports on the development of bending actuators based on poly(l-lactic acid) (PLLA)\/ionic liquid (IL) blends, through the incorporation of 40% wt. of the 1-ethyl-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][TFSI]) IL. The films, obtained by solvent casting at room temperature and 50 \u00b0C, were subjected to several post-thermal treatments at 70, 90, 120 and 140 \u00b0C, in order to modify the crystallinity of the films. The influence of the drying temperature and of [Emim][TFSI] blending on the morphological, structural, mechanical and electrical properties of the composite materials were studied. The IL induced the formation of a porous surface independently of the processing conditions. Moreover, the [Emim][TFSI] dopant and the post-thermal treatments at 70 \u00b0C promoted an increase of the degree of crystallinity of the samples. No significant changes were observed in the degree of crystallinity and Young Modulus for samples with thermal treatment between 70 and 140 \u00b0C. The viability of the developed high ionic conductive blends for applications as soft actuators was evaluated. A maximum displacement of 1.7 mm was achieved with the PLLA\/[Emim][TFSI] composite prepared at 50 \u00b0C and thermally treated at 140 \u00b0C, for an applied voltage of 10 Vpp, at a frequency of 100 mHz. This work highlights interesting avenues for the use of PLLA in the field of actuators.<\/jats:p>","DOI":"10.3390\/polym12051187","type":"journal-article","created":{"date-parts":[[2020,5,25]],"date-time":"2020-05-25T11:42:02Z","timestamp":1590406922000},"page":"1187","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Development of Poly(l-Lactic Acid)-Based Bending Actuators"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3118-4717","authenticated-orcid":false,"given":"Daniela","family":"M. Correia","sequence":"first","affiliation":[{"name":"CQ-VR, University of Tr\u00e1s-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal"},{"name":"Centre of Physics, University of Minho, 4710-057 Braga, Portugal"}]},{"given":"Liliana","family":"C. Fernandes","sequence":"additional","affiliation":[{"name":"Centre of Physics, University of Minho, 4710-057 Braga, Portugal"}]},{"given":"B\u00e1rbara","family":"Cruz","sequence":"additional","affiliation":[{"name":"Centre of Chemistry, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4680-0834","authenticated-orcid":false,"given":"Gabriela","family":"Botelho","sequence":"additional","affiliation":[{"name":"Centre of Chemistry, University of Minho, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7577-4938","authenticated-orcid":false,"given":"Ver\u00f3nica","family":"de Zea Bermudez","sequence":"additional","affiliation":[{"name":"CQ-VR, University of Tr\u00e1s-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal"},{"name":"Department of Chemistry, University of Tr\u00e1s-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6791-7620","authenticated-orcid":false,"given":"Senentxu","family":"Lanceros-M\u00e9ndez","sequence":"additional","affiliation":[{"name":"BCMaterials, Basque Center for Materials, Applications and Nanostructures, UPV\/EHU Science Park, 48940 Leioa, Spain"},{"name":"Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1016\/j.addr.2016.06.012","article-title":"Physical and mechanical properties of PLA, and their functions in widespread applications\u2014A comprehensive review","volume":"107","author":"Farah","year":"2016","journal-title":"Adv. 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