{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T23:58:43Z","timestamp":1769558323324,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T00:00:00Z","timestamp":1769472000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT-Portuguese Foundation for Science and Technology","award":["UID\/05256"],"award-info":[{"award-number":["UID\/05256"]}]},{"name":"CDRSP","award":["UID\/04044\/2025"],"award-info":[{"award-number":["UID\/04044\/2025"]}]},{"name":"ARISE","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JMMP"],"abstract":"<jats:p>Despite extensive research, predicting ejection forces during the injection moulding process remains challenging due to the complex calculation of the coefficient of friction. This coefficient comprises various components that are difficult to isolate, complicating independent predictions. Consequently, using literature-documented coefficient of friction for different material contacts often leads to discrepancies between the experimental data and the predictive models of ejection forces. The adhesion component is a particularly problematic aspect, and is frequently excluded from analyses due to the difficulties associated with measuring it directly. This study aims to present the development of a tool designed to measure both the friction and adhesion forces under conditions that replicate those of the injection moulding process. The measured values were then used to calculate the corresponding coefficients: the static coefficient of friction (COF) and the coefficient of adhesion (COA). The conducted measurements identified the most influential factors in both coefficient values using a Design of Experiments (DoE), revealing that replication temperature was the factor promoting the highest variation across all the tested polymers.<\/jats:p>","DOI":"10.3390\/jmmp10020045","type":"journal-article","created":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T10:27:11Z","timestamp":1769509631000},"page":"45","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Development and Validation of Equipment for Determining Friction and Adhesion Coefficients Under Conditions Comparable to the Injection Moulding Process"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5229-9652","authenticated-orcid":false,"given":"\u00c2ngela R.","family":"Rodrigues","sequence":"first","affiliation":[{"name":"IPC\u2013Institute for Polymers and Composites, University of Minho, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"},{"name":"DONE Lab\u2013Advanced Manufacturing of Products and Tools, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2176-6289","authenticated-orcid":false,"given":"M\u00e1rio S.","family":"Correia","sequence":"additional","affiliation":[{"name":"ESTG\u2013School of Technology and Management, Polytechnic of Leiria, 2411-901 Leiria, Portugal"},{"name":"CDRsp, Polytechnic of Leiria, 2430-028 Marinha Grande, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8964-400X","authenticated-orcid":false,"given":"Ant\u00f3nio J.","family":"Pontes","sequence":"additional","affiliation":[{"name":"IPC\u2013Institute for Polymers and Composites, University of Minho, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"},{"name":"DONE Lab\u2013Advanced Manufacturing of Products and Tools, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"977","DOI":"10.1007\/s00170-011-3573-2","article-title":"Analysis of Friction in the Ejection of Thermoplastic Mouldings","volume":"59","author":"Correia","year":"2011","journal-title":"Int. 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