{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:24:12Z","timestamp":1760149452003,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,7,26]],"date-time":"2023-07-26T00:00:00Z","timestamp":1690329600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["PTDC\/BII-BIO\/5626\/2020","UIDB\/05256\/2020","UIDP\/05256\/2020","CEECINST\/00156\/2018"],"award-info":[{"award-number":["PTDC\/BII-BIO\/5626\/2020","UIDB\/05256\/2020","UIDP\/05256\/2020","CEECINST\/00156\/2018"]}]},{"name":"IPC","award":["PTDC\/BII-BIO\/5626\/2020","UIDB\/05256\/2020","UIDP\/05256\/2020","CEECINST\/00156\/2018"],"award-info":[{"award-number":["PTDC\/BII-BIO\/5626\/2020","UIDB\/05256\/2020","UIDP\/05256\/2020","CEECINST\/00156\/2018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>The main objective of this work is to validate an in-line micro-slit rheometer and a micro-extrusion line, both designed for the in-line monitoring and production of filaments for 3D printing using small amounts of material. The micro-filament extrusion line is first presented and its operational window is assessed. The throughputs ranged between 0.045 kg\/h and 0.15 kg\/h with a maximum 3% error and with a melt temperature control within 1 \u00b0C under the processing conditions tested for an average residence time of about 3 min. The rheological micro slit is then presented and assessed using low-density polyethylene (LDPE) and cyclic olefin copolymer (COC). The excellent matching between the in-line micro-rheological data and the data measured with off-line rotational and capillary rheometers validate the in-line micro-slit rheometer. However, it is shown that the COC does not follow the Cox\u2013Merz rule. The COC filaments produced with the micro-extrusion line were successfully used in the 3D printing of specimens for tensile testing. The quality of both filaments (less than 6% variation in diameter along the filament\u2019s length) and printed specimens validated the whole micro-set-up, which was eventually used to deliver a rheological mapping of COC printability.<\/jats:p>","DOI":"10.3390\/mi14081496","type":"journal-article","created":{"date-parts":[[2023,7,27]],"date-time":"2023-07-27T01:27:46Z","timestamp":1690421266000},"page":"1496","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Experimental Validation of a Micro-Extrusion Set-Up with In-Line Rheometry for the Production and Monitoring of Filaments for 3D-Printing"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-3729-0086","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Sousa","sequence":"first","affiliation":[{"name":"Institute for Polymers and Composites, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"given":"Paulo F.","family":"Teixeira","sequence":"additional","affiliation":[{"name":"Institute for Polymers and Composites, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9936-8088","authenticated-orcid":false,"given":"Lo\u00efc","family":"Hilliou","sequence":"additional","affiliation":[{"name":"Institute for Polymers and Composites, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0790-5801","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Covas","sequence":"additional","affiliation":[{"name":"Institute for Polymers and Composites, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Saleh Alghamdi, S., John, S., Roy Choudhury, N., and Dutta, N.K. 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