{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T05:03:40Z","timestamp":1789707820125,"version":"4.0.1"},"reference-count":42,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,13]],"date-time":"2026-09-13T00:00:00Z","timestamp":1789257600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012190","name":"Ministry of Science and Higher Education","doi-asserted-by":"publisher","award":["DWD\/7\/0265\/2023"],"award-info":[{"award-number":["DWD\/7\/0265\/2023"]}],"id":[{"id":"10.13039\/501100012190","id-type":"DOI","asserted-by":"publisher"}]},{"award":["DWD\/7\/0265\/2023"],"award-info":[{"award-number":["DWD\/7\/0265\/2023"]}],"id":[{"id":"https:\/\/ror.org\/05dwvd537","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005033","name":"Bialystok University of Technology","doi-asserted-by":"publisher","award":["WZ\/WM-IIM\/5\/2026"],"award-info":[{"award-number":["WZ\/WM-IIM\/5\/2026"]}],"id":[{"id":"10.13039\/501100005033","id-type":"DOI","asserted-by":"publisher"}]},{"award":["WZ\/WM-IIM\/5\/2026"],"award-info":[{"award-number":["WZ\/WM-IIM\/5\/2026"]}],"id":[{"id":"https:\/\/ror.org\/02bzfsy61","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The structural, processing, and mechanical response of a multiphase poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)\/poly(butylene adipate-co-terephthalate) (PBAT)\/thermoplastic starch (TPS) matrix to two distinct glass fillers was investigated. Glass fibers and hollow glass spheres were incorporated by melt compounding and injection molding, while the unfilled blend served as the reference. Differential scanning calorimetry, X-ray diffraction, melt-flow-rate measurements, helium pycnometry, scanning electron microscopy with deep-learning-based segmentation, tensile, and Charpy impact tests were applied. At higher filler contents, the composite-level XRD-based crystallinity index decreased to approximately 47%, whereas the Scherrer-derived PHBV (110) coherent-domain size remained within approximately 21\u201324 nm. Preferred orientation, assessed independently from the PHBV reflection-intensity ratio, varied with filler type and content. Glass fibers progressively reduced melt flow and were associated with an increase in tensile modulus from 2.06 to 3.45 GPa and maximum tensile stress from 23.46 to 27.32 MPa at the highest investigated fiber content. Hollow glass spheres produced a non-monotonic melt-flow response, while the reduction in tensile performance at higher contents coincided with decreasing interparticle spacing and increasing specific external polymer\u2013glass interfacial area. Within the analyzed SEM fields, no pronounced filler-rich clustering was evident. Notched specimens remained brittle, whereas unnotched specimens retained impact strength above 10 kJ \u00d7 m\u22122. Overall, the two filler geometries exhibited distinct relationships among apparent melt flowability, crystalline organization, quantitative microstructural descriptors, and mechanical response.<\/jats:p>","DOI":"10.3390\/polym18182233","type":"journal-article","created":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T08:10:23Z","timestamp":1789373423000},"page":"2233","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Filler-Geometry-Dependent Crystallinity, Melt Flow, and Mechanical Response of Glass-Filled PHBV + PBAT + TPS Composites"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-8471-5579","authenticated-orcid":false,"given":"Magdalena","family":"Panto\u0142","sequence":"first","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"},{"name":"Grupa Azoty S.A., Kwiatkowskiego 8, 33-100 Tarn\u00f3w, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Klaudia","family":"Porzezinska","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3523-9786","authenticated-orcid":false,"given":"Krzysztof","family":"Nowik","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-2376-4078","authenticated-orcid":false,"given":"Ewa","family":"Borucinska-Parfieniuk","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2484-7519","authenticated-orcid":false,"given":"Mehmet","family":"Aladag","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3994-2957","authenticated-orcid":false,"given":"Adrian","family":"Dubicki","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3875-4820","authenticated-orcid":false,"given":"Krzysztof J.","family":"Kurzyd\u0142owski","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4432-9196","authenticated-orcid":false,"given":"Izabela B.","family":"Zg\u0142obicka","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Bialystok University of Technology, Wiejska 45C, 15-351 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"343","DOI":"10.4028\/www.scientific.net\/KEM.798.343","article-title":"The Effect of Poly(Butylene Adipate-co-Terephthalate) on Crystallization Behavior and Morphology of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)","volume":"798","author":"Duangphet","year":"2019","journal-title":"Key Eng. 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