{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T00:30:03Z","timestamp":1768437003830,"version":"3.49.0"},"reference-count":15,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,6,11]],"date-time":"2020-06-11T00:00:00Z","timestamp":1591833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MCTES","award":["POCI-01-0145-FEDER-017820"],"award-info":[{"award-number":["POCI-01-0145-FEDER-017820"]}]},{"name":"FCT\/MCTES","award":["UIBD\/00511\/2020"],"award-info":[{"award-number":["UIBD\/00511\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Titanium dioxide is considered the most efficient white pigment for opacification of thermoplastics. However, its high cost, combined with strong price oscillations due to production bottlenecks, has been driving the industry towards alternatives that might allow reducing the titanium dioxide content, while maintaining the product\u2019s opacity. A strategy commonly used in waterborne paints consists in adding hollow polymer particles to the formulation, therefore achieving opacification due to light refraction at the air\/polymer interface. In the current work, we show preliminary results that indicate that a similar strategy can be followed for thermoplastics opacification, as long as thermoset particles are used, in order to ensure preservation of the hollow geometry during melt-processing. Multi-vesiculated crosslinked styrene\u2013polyester particles, produced by a single-step double emulsion process, are used. Evidence of synergic interaction between the multi-hollow particles and titanium dioxide has been found.<\/jats:p>","DOI":"10.3390\/polym12061331","type":"journal-article","created":{"date-parts":[[2020,6,16]],"date-time":"2020-06-16T00:50:49Z","timestamp":1592268649000},"page":"1331","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Use of Multi-Hollow Polyester Particles as Opacifying Agent for Injection-Molded Polyethylene"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7724-8704","authenticated-orcid":false,"given":"Jo\u00e3o","family":"F. A. Silva","sequence":"first","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9756-5224","authenticated-orcid":false,"given":"T\u00e2nia","family":"M. T. Carvalho","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Margarida","family":"L. Almeida","sequence":"additional","affiliation":[{"name":"DEMAD, Department of Wood Engineering, Polytechnic Institute of Viseu, Campus Polit\u00e9cnico de Repeses, 3504-510 Viseu, Portugal"}]},{"given":"Paula","family":"Pereira","sequence":"additional","affiliation":[{"name":"Isolago, Estrada Nacional 3\u2013km 16, 2050-038 Aveiras de Baixo, Portugal"}]},{"given":"Helena","family":"Sousa","sequence":"additional","affiliation":[{"name":"Isolago, Estrada Nacional 3\u2013km 16, 2050-038 Aveiras de Baixo, Portugal"}]},{"given":"Jorge","family":"Martins","sequence":"additional","affiliation":[{"name":"DEMAD, Department of Wood Engineering, Polytechnic Institute of Viseu, Campus Polit\u00e9cnico de Repeses, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4557-7113","authenticated-orcid":false,"given":"Lu\u00edsa","family":"Carvalho","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"DEMAD, Department of Wood Engineering, Polytechnic Institute of Viseu, Campus Polit\u00e9cnico de Repeses, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4447-4473","authenticated-orcid":false,"given":"Fern\u00e3o","family":"D. Magalh\u00e3es","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,11]]},"reference":[{"key":"ref_1","first-page":"441","article-title":"A Review of the Production Cycle of Titanium Dioxide Pigment","volume":"5","author":"Vaca","year":"2014","journal-title":"Mater. Sci. Appl."},{"key":"ref_2","first-page":"88","article-title":"Keeping on the white track Optimising the efficiency of titanium dioxide in architectural paints","volume":"3","author":"Rommens","year":"2015","journal-title":"Eur. Coatings J."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Koleske, J. (2012). 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Coatings J."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/12\/6\/1331\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:37:50Z","timestamp":1760175470000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/12\/6\/1331"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,6,11]]},"references-count":15,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2020,6]]}},"alternative-id":["polym12061331"],"URL":"https:\/\/doi.org\/10.3390\/polym12061331","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,6,11]]}}}