{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T01:54:15Z","timestamp":1789523655183,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,4,22]],"date-time":"2023-04-22T00:00:00Z","timestamp":1682121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["52273042"],"award-info":[{"award-number":["52273042"]}]},{"name":"National Natural Science Foundation of China","award":["52073229"],"award-info":[{"award-number":["52073229"]}]},{"name":"National Natural Science Foundation of China","award":["20200029053002"],"award-info":[{"award-number":["20200029053002"]}]},{"name":"National Natural Science Foundation of China","award":["2021KW-52"],"award-info":[{"award-number":["2021KW-52"]}]},{"name":"Aeronautical Science Foundation of China","award":["52273042"],"award-info":[{"award-number":["52273042"]}]},{"name":"Aeronautical Science Foundation of China","award":["52073229"],"award-info":[{"award-number":["52073229"]}]},{"name":"Aeronautical Science Foundation of China","award":["20200029053002"],"award-info":[{"award-number":["20200029053002"]}]},{"name":"Aeronautical Science Foundation of China","award":["2021KW-52"],"award-info":[{"award-number":["2021KW-52"]}]},{"name":"Natural Science Foundation of Shaanxi Province","award":["52273042"],"award-info":[{"award-number":["52273042"]}]},{"name":"Natural Science Foundation of Shaanxi Province","award":["52073229"],"award-info":[{"award-number":["52073229"]}]},{"name":"Natural Science Foundation of Shaanxi Province","award":["20200029053002"],"award-info":[{"award-number":["20200029053002"]}]},{"name":"Natural Science Foundation of Shaanxi Province","award":["2021KW-52"],"award-info":[{"award-number":["2021KW-52"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Biodegradable polylactic acid (PLA) foams with open-cell structures are good candidates for oil\u2013water separation. However, the foaming of PLA with high-expansion and uniform cell morphology by the traditional supercritical carbon dioxide microcellular foaming method remains a big challenge due to its low melting strength. Herein, a green facile strategy for the fabrication of open-cell fully biodegradable PLA-based foams is proposed by introducing the unique stereocomplexation mechanism between PLLA and synthesized star-shaped PDLA for the first time. A series of star-shaped PDLA with eight arms (8-s-PDLA) was synthesized with different molecular weights and added into the PLLA as modifiers. PLLA\/8-s-PDLA foams with open-cells structure and high expansion ratios were fabricated by microcellular foaming with green supercritical carbon dioxide. In detail, the influences of induced 8-s-PDLA on the crystallization behavior, rheological properties, cell morphology and consequential oil\u2013water separation performance of PLA-based foam were investigated systemically. The addition of 8-s-PDLA induced the formation of SC-PLA, enhancing crystallization by acting as nucleation sites and improving the melting strength through acting as physical cross-linking points. The further microcellular foaming of PLLA\/8-s-PDLA resulted in open-cell foams of high porosity and high expansion ratios. With an optimized foaming condition, the PLLA\/8-s-PDLA-13K foam exhibited an average cell size of about 61.7 \u03bcm and expansion ratio of 24. Furthermore, due to the high porosity of the interconnected open cells, the high-absorption performance of the carbon tetrachloride was up to 37 g\/g. This work provides a facile green fabrication strategy for the development of environmentally friendly PLA foams with stable open-cell structures and high expansion ratios for oil\u2013water separation.<\/jats:p>","DOI":"10.3390\/polym15091984","type":"journal-article","created":{"date-parts":[[2023,4,24]],"date-time":"2023-04-24T02:06:11Z","timestamp":1682301971000},"page":"1984","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["High-Expansion Open-Cell Polylactide Foams Prepared by Microcellular Foaming Based on Stereocomplexation Mechanism with Outstanding Oil\u2013Water Separation"],"prefix":"10.3390","volume":"15","author":[{"given":"Dongsheng","family":"Li","sequence":"first","affiliation":[{"name":"Key Laboratory of Macromolecular Science & Technology of Shaanxi Province, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuai","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Macromolecular Science & Technology of Shaanxi Province, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zezhong","family":"Zhao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Macromolecular Science & Technology of Shaanxi Province, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhenyun","family":"Miao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Macromolecular Science & Technology of Shaanxi Province, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guangcheng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Macromolecular Science & Technology of Shaanxi Province, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuetao","family":"Shi","sequence":"additional","affiliation":[{"name":"Key Laboratory of Macromolecular Science & Technology of Shaanxi Province, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1151","DOI":"10.1016\/j.cej.2017.07.024","article-title":"Use of stereocomplex crystallites for fully-biobased microcellular low-density poly(lactic acid) foams for green packaging","volume":"327","author":"Wang","year":"2017","journal-title":"Chem. 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