{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T06:11:59Z","timestamp":1762409519922,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,4,24]],"date-time":"2019-04-24T00:00:00Z","timestamp":1556064000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"AIProcMat@N2020 - Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020\u201d, with the reference NORTE-01-0145-FEDER-000006, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2","award":["NORTE-01-0145-FEDER-000006"],"award-info":[{"award-number":["NORTE-01-0145-FEDER-000006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Processes"],"abstract":"<jats:p>A kinetic model describing aqueous acrylamide homopolymerization and copolymerization of acrylamide with methylene bisacrylamide, leading to hydrogel formation, is presented and applied in the simulation of these reaction processes. This modeling approach is based on population balances of generating functions and, besides the crosslinking mechanisms inherent to network formation, other specific kinetic steps important in acrylamide polymerization (e.g., branching due to backbiting) are considered in the simulation tool developed. The synthesis of acrylamide polymers and hydrogels was performed at 26 \u00b0C and at 40 \u00b0C using two different initiation systems. The formation of such materials was monitored using in-line static light scattering (SLS), and the spatial inhomogeneity of the final hydrogels was also measured using this experimental technique. It is shown that the simulations are helpful in describing information provided by SLS in-line monitoring, namely in the early stages of polymerization with the transition from dilute to semi-dilute regime. Indeed, it finds a plausible match between the critical overlap polymer concentration and gelation, this later leading to the observed spatial heterogeneity of the hydrogels. Usefulness of the kinetic model for defining operation conditions (initial composition, semi-batch feed policies, chain transfer, etc.) in making the shift from gelation to the semi-dilute regime is discussed, and the extension of this approach to processes enabling a higher control of gelation (e.g., controlled radical polymerization) is also prospected.<\/jats:p>","DOI":"10.3390\/pr7040237","type":"journal-article","created":{"date-parts":[[2019,4,25]],"date-time":"2019-04-25T03:02:59Z","timestamp":1556161379000},"page":"237","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Static Light Scattering Monitoring and Kinetic Modeling of Polyacrylamide Hydrogel Synthesis"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3396-3615","authenticated-orcid":false,"given":"Catarina","family":"Gomes","sequence":"first","affiliation":[{"name":"LSRE and Centro de Investiga\u00e7\u00e3o de Montanha (CIMO), Instituto Polit\u00e9cnico de Bragan\u00e7a, Campus de Santa Apol\u00f3nia, 5300-253 Bragan\u00e7a, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7369-382X","authenticated-orcid":false,"given":"Rolando C.S.","family":"Dias","sequence":"additional","affiliation":[{"name":"LSRE and Centro de Investiga\u00e7\u00e3o de Montanha (CIMO), Instituto Polit\u00e9cnico de Bragan\u00e7a, Campus de Santa Apol\u00f3nia, 5300-253 Bragan\u00e7a, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7807-4275","authenticated-orcid":false,"given":"M\u00e1rio Rui P.F.N.","family":"Costa","sequence":"additional","affiliation":[{"name":"LSRE-Faculdade de Engenharia da Universidade do Porto, Rua Roberto Frias s\/n, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Penlidis, A. 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