PolymersPub Date : 2025-09-30DOI: 10.3390/polym17192640
Pengfei Chen, Ying Xiong, Daijun Du, Rui Jiang, Jintao Li
{"title":"Synthesis of Linear Modified Siloxane-Based Thickeners and Study of Their Phase Behavior and Thickening Mechanism in Supercritical Carbon Dioxide.","authors":"Pengfei Chen, Ying Xiong, Daijun Du, Rui Jiang, Jintao Li","doi":"10.3390/polym17192640","DOIUrl":"10.3390/polym17192640","url":null,"abstract":"<p><p>To address critical limitations of ultra-low viscosity supercritical CO<sub>2</sub> fracturing fluids, including excessive fluid loss and inadequate proppant transport capacity, a series of thickeners designed to significantly enhance CO<sub>2</sub> viscosity were synthesized. Initially, FT-IR and <sup>1</sup>H NMR characterization confirmed successful chemical reactions and incorporation of both solvation-enhancing and -thickening functional groups. Subsequently, dissolution and thickening performance were evaluated using a custom-designed high-pressure vessel featuring visual observation capability, in-line viscosity monitoring, and high-temperature operation. All thickener systems exhibited excellent solubility, with 5 wt% loading elevating CO<sub>2</sub> viscosity to 3.68 mPa·s. Ultimately, molecular simulations performed in Materials Studio elucidated the mechanistic basis, electrostatic potential (ESP) mapping, cohesive energy density analysis, intermolecular interaction energy, and radial distribution function comparisons. These computational approaches revealed dissolution and thickening mechanisms of polymeric thickeners in CO<sub>2</sub>.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12527082/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-29DOI: 10.3390/polym17192633
Daniela Predoi, Carmen Steluta Ciobanu, Simona Liliana Iconaru, Roxana Alexandra Petre, Krzysztof Rokosz, Steinar Raaen, Mihai Valentin Predoi
{"title":"Development and Physico-Chemical and Antibacterial Characterization of Chromium-Doped Hydroxyapatite in a Chitosan Matrix Coating.","authors":"Daniela Predoi, Carmen Steluta Ciobanu, Simona Liliana Iconaru, Roxana Alexandra Petre, Krzysztof Rokosz, Steinar Raaen, Mihai Valentin Predoi","doi":"10.3390/polym17192633","DOIUrl":"10.3390/polym17192633","url":null,"abstract":"<p><p>Chromium-doped hydroxyapatite (7CrHAp) and chromium-doped hydroxyapatite in chitosan matrix (7CrHAp-CH) coatings were synthesized in order to address the need for biomaterials with improved physico-chemical and biological properties for biomedical applications. Both chromium-doped hydroxyapatite (7CrHAp) and chromium-doped hydroxyapatite in chitosan matrix (7CrHAp-CH) coatings could represent promising materials for biomedical applications due to their superior properties. This study aims to evaluate the physico-chemical and in vitro biological properties of 7CrHAp and 7CrHAp-CH coatings to determine the impact of chitosan incorporation on the physico-chemical and biological features. The results reported in this study indicate that addition of chitosan improves surface uniformity and biological properties, highlighting their potential for uses in biomedical applications. In this study, coatings of chromium-doped hydroxyapatite (7CrHAp, with x<sub>Cr</sub> = 0.07) and its composite variant embedded in a chitosan matrix (7CrHAp-CH) were systematically analyzed using a suite of characterization techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and metallographic microscopy (MM). The results of the XRD analysis revealed that the average crystal size was 19.63 nm for 7CrHAp and 16.29 nm for 7CrHAp-CH, indicating a decrease in crystallite size upon CH incorporation. The films were synthesized via the dip coating method using stable suspensions, whose stability was assessed through ultrasonic measurements (double-distilled water serving as the reference medium). The values obtained for the stability parameter were 2.59·10<sup>-6</sup> s<sup>-1</sup> for 7CrHAp, 8.64·10<sup>-7</sup> s<sup>-1</sup> for 7CrHAp-CH, and 3.14·10<sup>-7</sup> s<sup>-1</sup> for chitosan (CH). These data underline that all samples are stable: CH is extremely stable, followed by 7CrHAp-CH (very stable) and 7CrHAp (stable). The in vitro biocompatibility of the 7CrHAp and 7CrHAp-CH coatings was evaluated with the aid of the MG63 cell line. The cytotoxic potential of these coatings towards MG63 cells was quantified using the MTT assay after 24 and 48 h of incubation. Our results highlight that both 7CrHAp and 7CrHAp-CH coatings exhibit high biocompatibility with MG63 cells, maintaining cell viability above 90% at both incubation times, thus supporting osteoblast-like cell proliferation. Furthermore, the antimicrobial efficacy of both 7CrHAp and 7CrHAp-CH samples was evaluated in vitro against the <i>Pseudomonas aeruginosa</i> 27853 ATCC (<i>P. aeruginosa</i>) reference strain. The in vitro antibacterial activity of the 7CrHAp and 7CrHAp-CH coatings was further evaluated against <i>Pseudomonas aeruginosa</i> 27853 ATCC (<i>P. aeruginosa</i>), <i>Escherichia coli</i> ATCC 25922 (<i>E. coli</i>)","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12527083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-29DOI: 10.3390/polym17192635
Minghao Zhang, Xudong Hou, Qifa Yao, Hanyu Chen, Zuting Wei, Yue Zhao, Zhishuai Geng, Fanzhi Yang, Min Xia, Yunjun Luo
{"title":"Plasticizer-Enabled Solvent-Free Curing of Self-Healing Binder System for Energetic Materials.","authors":"Minghao Zhang, Xudong Hou, Qifa Yao, Hanyu Chen, Zuting Wei, Yue Zhao, Zhishuai Geng, Fanzhi Yang, Min Xia, Yunjun Luo","doi":"10.3390/polym17192635","DOIUrl":"10.3390/polym17192635","url":null,"abstract":"<p><p>Solvent processing hampers the reliability and energy density of self-healing binders for energetic materials. We report a solvent-free curing route for a Diels-Alder self-healing furanyl-terminated polybutadiene enabled by a functional external plasticizer, dibutyl phthalate (DBP), which acts not only to lower the viscosity of the binder but to disperse the high-melting bismaleimide, thereby driving crosslinked network formation. The 50 wt% DBP-plasticized film healed a pre-cut crack in 5 min at 120 °C and recovered nearly full mechanical properties after 24 h at 60 °C. Based on this binder system, a self-healing solid propellant with 80 wt% solid content was solvent-free cast into a dense and void-free grain that healed surface cracks within 5 min at 120 °C. This solvent-free approach overcomes the limitations of solvent-based processing and offers a viable fabrication route for self-healing energetic materials.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12527010/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-29DOI: 10.3390/polym17192634
Siying Wang, Dengxia Wang, Qi An, Jiakai Li, Kai Chong, Xinbo Wang, Jingjing Liu, Keyong Xie, Xuejun Hou, Jian Hou, Yan Sun
{"title":"Multi-Regional Natural Aging Behaviors and Degradation Mechanisms of Polyurethane-Coated Fabrics Under Coupled Multiple Environmental Factors.","authors":"Siying Wang, Dengxia Wang, Qi An, Jiakai Li, Kai Chong, Xinbo Wang, Jingjing Liu, Keyong Xie, Xuejun Hou, Jian Hou, Yan Sun","doi":"10.3390/polym17192634","DOIUrl":"10.3390/polym17192634","url":null,"abstract":"<p><p>Polyurethane-coated fabrics are widely employed as tarpaulin materials. However, due to the long duration and large space requirements of natural exposure tests, studies on fabric degradation remain scarce. To systematically investigate the natural aging patterns and mechanisms of polyurethane-coated fabrics, this study conducted 24-month natural aging tests in three representative regions: Xishuangbanna (tropical monsoon climate), Xiamen (subtropical maritime monsoon climate), and Jinan (temperate monsoon climate). Changes in appearance, mechanical properties, surface morphology, elemental composition, and microstructure were thoroughly analyzed. The results indicated that gloss decreased by over 60%, the color difference exceeded 5.8, and tear strength was reduced by more than 50%. SEM, ATR-FTIR, and XPS analyses revealed that hydrolysis and oxidation occurred in the coating, leading to coating thinning, fiber exposure, and even damage. In Xishuangbanna, high temperature, high humidity, and strong solar radiation are responsible for the most severe degradation of fabrics. High temperature, humidity, and salt fog synergistically accelerated the aging process. In Jinan, significant thermal strain contributed to deterioration, and fabrics exhibited the mildest degradation. This multi-region natural exposure study realistically simulates in-service aging behavior, providing important validation for accelerated laboratory aging methods, product reliability improvement, and service-life modeling.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12527080/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-29DOI: 10.3390/polym17192632
Junjie Huang, Hongmei Pan, Deliang Le, Zengxin Ouyang, Kemei Pei
{"title":"Synthesis and Properties Study of Liquid Crystalline Epoxy Resin Containing Azomethine-Based Monomeric Mesogens.","authors":"Junjie Huang, Hongmei Pan, Deliang Le, Zengxin Ouyang, Kemei Pei","doi":"10.3390/polym17192632","DOIUrl":"10.3390/polym17192632","url":null,"abstract":"<p><p>The epoxy monomer N,1-bis(4-(2-oxiranemethoxy)phenyl)methylamine (HBAP-EP) was synthesized through the Schiff base reaction and epichlorohydrin method, and the HBAP-EP monomer was cured using p-aminobenzene sulfonamide (SAA). Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and polarizing optical microscopy (POM) demonstrated that the epoxy monomer exhibits reversible liquid crystal properties, and the liquid crystal fraction of the monomer can reach 14.4% after curing at 120 °C. The fracture toughness of the resin cured at 120 °C can reach 0.93 KJ·m<sup>-2</sup>, and its thermal conductivity is 0.3229 W·(m·K)<sup>-1</sup>, both of which are higher than those of ordinary epoxy resin.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12526637/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-28DOI: 10.3390/polym17192622
Ana Paula Duarte, Pedro R da Costa, Manuel Freitas
{"title":"Multi-Layer Laminate of Fibreglass Thermoplastic Composite Reinforced with Fused Filament Fabrication TPU Layers.","authors":"Ana Paula Duarte, Pedro R da Costa, Manuel Freitas","doi":"10.3390/polym17192622","DOIUrl":"10.3390/polym17192622","url":null,"abstract":"<p><p>Thermoset fibre-reinforced composites are widely used in high-end industries, but a growing demand for more sustainable and recyclable alternatives conveyed the research efforts towards thermoplastics. To expand their usage, new approaches to their manufacture and mechanical performance must be tackled and tailored to each engineering challenge. The present study designed, manufactured and tested advanced multi-layer laminated composites of thermoplastic polypropylene prepreg reinforced with continuous woven fibreglass with interlayer toughening through thermoplastic polyurethane elastomer (TPU) layers manufactured by fused filament fabrication. The manufacturing process was iteratively optimized, resulting in successful adhesion between layers. Three composite configurations were produced: baseline glass fibre polypropylene (GFPP) prepreg and two multi-layer composites, with solid and honeycomb structured TPU layers. Thermal and mechanical analyses were conducted with both the polyurethane elastomer and the manufactured laminates. Tensile testing was conducted on additively manufactured polyurethane elastomer specimens, while laminated composites were tested in three-point bending. The results demonstrated the potential of the developed laminates. TPU multi-layer laminates exhibit higher thermal stability compared to the baseline GFPP prepreg-based composites. The addition of elastomeric layers decreases the flexural modulus but increases the ability to sustain plastic deformation. Multi-layer laminate composites presenting honeycomb TPU layers exhibit improved geometric and mechanical consistency, lower delamination and fibre breakage, and a high elastic recoverability after testing.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12526647/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-28DOI: 10.3390/polym17192625
Arkadiusz Kloziński, Paulina Jakubowska, Adam Piasecki, Dorota Czarnecka-Komorowska
{"title":"The Multiple Recycling Process of Polypropylene Composites with Glass Fiber in Terms of Grinding Efficiency and Selected Properties of Recirculated Products.","authors":"Arkadiusz Kloziński, Paulina Jakubowska, Adam Piasecki, Dorota Czarnecka-Komorowska","doi":"10.3390/polym17192625","DOIUrl":"10.3390/polym17192625","url":null,"abstract":"<p><p>This study comprehensively discusses the effect of multiple material recycling (five recycling cycles with the same technological conditions: injection molding → grinding → drying → injection molding → …) of commercial polypropylene-glass fiber composites (PPGF) (PP + 10, 20 and 30 wt.% GF) on the performance of the grinding process and the granulometric characteristics of the obtained regrinds, as well as selected surface, mechanical and thermal properties of the composites. An increase in mass (<i>E<sub>m</sub></i>) and volume (<i>E<sub>v</sub></i>) grinding efficiency was confirmed, along with an increase in GF content in the composite and the number of recycling cycles. Both the GF additive and the number of recycling cycles contributed to the deterioration of the aesthetic qualities of the composites (darkening and reduction in gloss). Slight changes in the surface hardness of the test materials were observed as a function of the number of recycling cycles, from 3 to 4% after five recycling cycles. The adverse effect of multiple recycling on the mechanical and thermal properties of PP and PPGF composites has been confirmed. The occurrence and increase in carbonyl index (<i>CI</i>) values, as a function of multiples recycling, was confirmed for a composite containing 20 wt.% GF (<i>CI</i> in the range from 0.045 to 0.092) and for PPGF containing 30 wt.% GF (<i>CI</i> in the range from 0.193 to 0.272). The effect of multiple material recycling on the glass fiber structure in the tested composites was also investigated using scanning electron microscopy (SEM) and optical microscopy. The issues of grinding and changes in the surface properties of PPGF composites in multiple material recycling processes discussed in this article may constitute a source of practical knowledge that will contribute to increasing the use of this type of secondary composite in industrial plastics processing processes.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12526444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electropolymerized PAA as a Functional Matrix for CeO<sub>2</sub>-NiO Hybrid Electrocatalysts for Efficient Water Oxidation.","authors":"Mrunal Bhosale, Pritam J Morankar, Yeonsu Lee, Hajin Seo, Chan-Wook Jeon","doi":"10.3390/polym17192631","DOIUrl":"10.3390/polym17192631","url":null,"abstract":"<p><p>Electrochemical water splitting has emerged as a pivotal strategy for advancing sustainable and renewable energy technologies. However, its practical deployment is often hampered by sluggish reaction kinetics, large overpotentials, and the high cost of efficient electrocatalysts. To overcome these critical challenges, a novel bifunctional electrocatalyst based on electropolymerized CeO<sub>2</sub>-NiO with polyacrylic acid (Ce-Ni-PAA) has been rationally engineered for overall water splitting. The strategic incorporation of conductive polymer framework enables effective modulation of the local electronic structure, enhances charge transport pathways, and maximizes the density of electrochemically accessible active sites, thereby substantially boosting catalytic performance. When evaluated in a 1 M KOH alkaline medium, the optimized Ce-Ni-PAA<sub>0.5</sub>/NF hybrid demonstrates remarkable catalytic activity with 366.5 mV overpotential at 50 mA cm<sup>-2</sup>, coupled with lower Tafel slope of 93.5 mV dec<sup>-1</sup>. Additionally, the Ce-Ni-PAA<sub>0.5</sub>/NF electrocatalyst exhibits exceptional ECSA of 1092.3 cm<sup>2</sup>, which confirms the presence of a significantly larger number of electrochemically active sites. The electrocatalyst retains its performance even after 5000 continuous cycles of operation. The superior performance is attributed to the synergistic effects arising from the enriched composition, efficient electron transport channels, and abundant catalytic centers. Collectively, this study not only highlights the significance of rational structural and compositional design but also offers valuable insights toward the development of next-generation, cost-effective bifunctional electrocatalysts with strong potential for scalable water splitting and clean energy applications.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12526815/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-28DOI: 10.3390/polym17192629
Lingping Kong, Peiyu Du, Lizhou Pei, Dan Sun
{"title":"The Role of TEMPO/NaBr/NaClO in Hemp Fiber Oxidation: Deciphering the Mechanism and Reaction Kinetics.","authors":"Lingping Kong, Peiyu Du, Lizhou Pei, Dan Sun","doi":"10.3390/polym17192629","DOIUrl":"10.3390/polym17192629","url":null,"abstract":"<p><p>In this study, the oxidation of industrial hemp staple fibers by the TEMPO/NaBr/NaClO system was explored by the real-time monitoring of the changes in reaction rate, selective oxidative conversion, and reaction time under different operating conditions such as TEMPO usage, NaBr usage, NaClO usage, reaction time, and reaction temperature. We propose a variable-speed competition mechanism between NaClO and TEMPO, which provides experimental support for the long-standing hypothesis that hypochlorite delays acid formation through modulation of the HOCl/OCl<sup>-</sup> and HOBr/OBr<sup>-</sup> equilibrium dynamics. The innovative use of combined analysis for several consecutive first-order reactions to investigate the rate-limiting reactions of TEMPO, TEMPO<sup>+</sup>, and TEMPOH over a range of concentrations revealed that the reaction that generates TEMPOH is the key rate-limiting reaction. We characterize the apparent oxidation kinetics of industrial hemp staple fiber in the TEMPO/NaBr/NaClO system using a pseudo-first-order kinetic model, revealing distinct apparent reaction rates across both primary and secondary bast fiber regions. This paper explained the difference in reaction rate between the two aspects of microfibril spatial structure and cellulose crystal structure. The single-factor analysis indicates that reaction time and temperature exert the most significant influence on the conversion rate of selective oxidation within this system.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12526754/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PolymersPub Date : 2025-09-28DOI: 10.3390/polym17192623
Kai Yang, Wenyuan Huang, Mutian Sun, Zhixian Zheng, Hongwei Lin
{"title":"Effect of Fiber Characteristics on Cracking Resistance Properties of Stone Mastic Asphalt (SMA) Mixture.","authors":"Kai Yang, Wenyuan Huang, Mutian Sun, Zhixian Zheng, Hongwei Lin","doi":"10.3390/polym17192623","DOIUrl":"10.3390/polym17192623","url":null,"abstract":"<p><p>Cracking is a critical distress that reduces an asphalt pavement's service life, and fiber reinforcement is an effective strategy to enhance anti-cracking capacity. However, the effects of fiber type, morphology, and length on key cracking modes remain insufficiently understood, limiting rational fiber selection in practice. This study systematically evaluated the influence of four representative fiber types on the anti-cracking performance of Stone Mastic Asphalt (SMA) mixture, combining mechanical testing and microstructural analysis. The fibers included lignin fiber (LF); polyester fiber (PF); chopped basalt fiber (CBF) with lengths of 3 mm, 6 mm, 9 mm; and flocculent basalt fiber (FBF). Key mechanical tests assessed specific cracking behaviors: three-point bending (low-temperature cracking), indirect tensile (tensile cracking), pre-cracked semi-circular bending (crack propagation), overlay (reflective cracking), and four-point bending (fatigue resistance) tests. A scanning electron microscopy (SEM) test characterized fiber morphology and fiber-asphalt interface interactions, revealing microstructural mechanisms underlying performance improvements. The results showed that all fibers improved anti-cracking performance, but their efficacy varied with fiber type, appearance, and length. PF exhibited the best low-temperature cracking resistance, with a 26.8% increase in bending strength and a 16.6% increase in maximum bending strain. For tensile and crack propagation resistance, 6 mm CBF and FBF outperformed the other fibers, with fracture energy increases of up to 53.2% (6 mm CBF) and CT<sub>index</sub> improvements of 72.8% (FBF). FBF optimized reflective cracking resistance, increasing the loading cycles by 48.0%, while 6 mm CBF achieved the most significant fatigue life improvement (36.9%) by balancing rigidity and deformation. Additionally, SEM analysis confirmed that effective fiber dispersion and strong fiber-asphalt bonding were critical for enhancing stress transfer and inhibiting crack initiation/propagation. These findings provide quantitative insights into the relationship between fiber characteristics (type, morphology, length) and anti-cracking performance, offering practical guidance for rational fiber selection to improve pavement durability.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 19","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12526559/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145302815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}