{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T10:11:40Z","timestamp":1789035100094,"version":"build-2803163510"},"reference-count":48,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T00:00:00Z","timestamp":1788912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Carbon-fiber-reinforced epoxy (CFRP) composites are widely used in aerospace structures because of their high specific strength and modulus; however, matrix cracking and interlaminar delamination induced by low-velocity impact compromise their structural safety. To overcome the difficulty of simultaneously improving interfacial strength and impact resistance through uniform nanomodification, a pearl-inspired gradient interfacial architecture incorporating a through-thickness distribution of polyhedral oligomeric silsesquioxane (POSS) was developed and compared with unmodified and uniformly modified CFRP laminates. SEM\/EDS, TEM, double-cantilever-beam testing, low-velocity impact testing, compression-after-impact (CAI) testing, and micro-CT were combined to examine the effects of POSS spatial distribution on interfacial morphology, Mode I interlaminar fracture toughness, and impact-damage evolution. POSS incorporation increased interfacial roughness and produced nanoscale POSS-rich domains within the epoxy matrix. Although uniform addition of 0.5 wt% POSS increased the mean CAI strength to 142 MPa, the Mode I interlaminar fracture toughness decreased to 0.479 kJ\u00b7m\u22122, revealing a trade-off in performance. By contrast, the gradient interface combined a high-POSS region with low-POSS regions that retained greater matrix continuity, thereby integrating material modification with through-thickness structural regulation. The gradient laminate showed more segmented crack paths and damage dispersion while suppressing continuous delamination. In the present tests, the gradient CFRP laminate exhibited a Mode I interlaminar fracture toughness of 1.342 kJ\u00b7m\u22122 (n = 1) and a mean CAI strength of 192 MPa (n = 3), corresponding to descriptive increases of approximately 148% and 113.3%, respectively, relative to the unmodified laminate. These results indicate that the response of the tested laminates depends not only on POSS content but also on its spatial distribution, providing an interfacial-design strategy for high-damage-tolerance CFRP laminates.<\/jats:p>","DOI":"10.3390\/polym18182199","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T14:02:48Z","timestamp":1788962568000},"page":"2199","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Performance of Multi-Gradient Biomimetic POSS-Toughened CFRP Laminates with a Pearl-Inspired Hard-Soft Interfacial Architecture"],"prefix":"10.3390","volume":"18","author":[{"given":"Gefeng","family":"Xiang","sequence":"first","affiliation":[{"name":"Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China"},{"name":"Scientific and Technological Innovation Center, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"given":"Shuwei","family":"Sun","sequence":"additional","affiliation":[{"name":"Scientific and Technological Innovation Center, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Yujie","family":"Wang","sequence":"additional","affiliation":[{"name":"Scientific and Technological Innovation Center, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"given":"Baorui","family":"Jia","sequence":"additional","affiliation":[{"name":"Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Changqing","family":"Li","sequence":"additional","affiliation":[{"name":"Scientific and Technological Innovation Center, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"}]},{"given":"Mingli","family":"Qin","sequence":"additional","affiliation":[{"name":"Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4691","DOI":"10.1038\/s41467-025-59848-2","article-title":"Additive manufacturing of carbon fiber-reinforced thermoset composites via in-situ thermal curing","volume":"16","author":"Dojan","year":"2025","journal-title":"Nat. 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