Polymer Testing最新文献

{"title":"Resistance of CNT film toughened composite laminates under high-speed impact: Experimental and numerical study","authors":"L.I. Zhouyi ,&nbsp;L.I. Jiming ,&nbsp;L.I.U. Yan ,&nbsp;J.I.A. Pengcheng ,&nbsp;C.H.A.O. Huan","doi":"10.1016/j.polymertesting.2025.108712","DOIUrl":"10.1016/j.polymertesting.2025.108712","url":null,"abstract":"<div><div>This paper conducted high-speed impact tests for the carbon fiber resin matrix composite laminates toughened by multi-walled carbon nanotubes (MWCNTs) interlayers. Numerical simulations were conducted based on the tests by using the cohesive model with rate sensitivity and CNT toughening mechanism. It shows that the FEM (Finite element method) model can effectively predict the impact behavior of CNTs interlaminar toughened composites under high-speed impact. The influence and mechanism of CNTs on materials under impact were revealed, and it was found that the addition of CNTs can help materials resist delamination during impact and ensure the integrity of the laminate structure.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108712"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Injectable double network hydrogel with adjustable stiffness for modulation of macrophage polarization","authors":"Jinxin Wu ,&nbsp;Bing Han ,&nbsp;Shili Ai ,&nbsp;Aijing Wang ,&nbsp;Yilin Song ,&nbsp;Moran Jin ,&nbsp;Xiaozhong Qu ,&nbsp;Xiaoyan Wang","doi":"10.1016/j.polymertesting.2024.108685","DOIUrl":"10.1016/j.polymertesting.2024.108685","url":null,"abstract":"<div><div>Substrate stiffness can regulate macrophage polarization to support tissue repair in tissue engineering applications. Understanding the mechanisms of stiffness sensing is valuable for applying this knowledge to stiffness-related inflammatory diseases. In this study, we examined IACs-related integrins related to stiffness-sensitive macrophage polarization by constructing an injectable double-network (DN) hydrogel with varying stiffness. Inflammatory cytokine expression decreased as substrate stiffness increased (from 19.9 to 125.7 kPa), with medium stiffness (84.8 kPa) inducing macrophages to an increased level of anti-inflammatory polarization. Improved adhesion and elevated expression levels of ITGA5, ITGA3, and ITGAV in macrophages on the softer hydrogels highlighted the role of integrins in stiffness-regulated macrophage polarization. Inhibition of integrins using ethylenediaminetetraacetic acid (EDTA) abolished differences in macrophage polarization across the three groups, further confirming the central role of integrins. These findings suggest that, in tissue engineering, selecting appropriate substrate stiffness or gradient stiffness hydrogel could align with the optimal mechanical environment required for specific cell growth and function. Additionally, the critical role of integrins in mediating mechanical transduction may provide new therapeutic targets for treating certain stiffness-related inflammatory diseases.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108685"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developing a more representative friction and wear simulator for tire tread compounds","authors":"E.H. Plaschka,&nbsp;K. Akutagawa,&nbsp;E. Di Federico,&nbsp;J.J.C. Busfield","doi":"10.1016/j.polymertesting.2025.108688","DOIUrl":"10.1016/j.polymertesting.2025.108688","url":null,"abstract":"<div><div>This study outlines a novel method to evaluate friction and wear performance in tire tread compounds. This new laboratory method takes into account the realistic contact force of a tread block impacting the road during each revolution of the tire. The dynamic contact between the sample and the abrader is simulated in a manner which more closely replicates a real tire's contact behaviour. The contact period accounts for the correct timing and the contact pressure that is typical for a passenger car driving under low-speed conditions. Two styrene-butadiene rubber (SBR) tyre tread compounds each filled with the same volume fraction of carbon black were vulcanized and abraded under this loading sequence. An analysis of the friction and the evolution of wear morphology are described in detail to provide insight into the governing mechanisms that determine tire tread performance.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108688"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient chemical recycling of poly(L-lactic acid) via either alcoholysis to alkyl lactate or thermal depolymerization to L-lactide promoted by Zn(II) catalysts","authors":"Maria Gentile ,&nbsp;Licia Gaeta ,&nbsp;Stefano Brenna ,&nbsp;Claudio Pellecchia","doi":"10.1016/j.polymertesting.2025.108727","DOIUrl":"10.1016/j.polymertesting.2025.108727","url":null,"abstract":"<div><div>Poly(lactic acid) (PLA), a commercially fully bio-based and biodegradable polymer, stands out as a sustainable alternative to commodity plastics. Its current end-of-life management involves composting, but chemical recycling would be more appropriate for a circular economy model. Here we report two very efficient chemical recycling pathways for commercial high molar mass and highly crystalline PLA samples, both ones promoted by different imidazole[1,5-<em>a</em>]pyrid-3-yl)phenolate Zn(II) catalysts: (i) alcoholysis was easily achieved by simply treating the polymer samples in boiling methanol in the presence of 1 % Zn(II) catalyst, resulting in up to 99 % yield and selectivity in methyl lactate; and (ii) chemical recycling to the monomer was achieved by heating the polymer samples at 180 °C under vacuum or in a nitrogen flow in the presence of 0.1 % Zn(II) catalyst and a highly boiling alcohol, resulting in up to 99 % yield of L-lactide, having high chemical and steric purity, which could be repolymerized without any further purification.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108727"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanically reinforced and flame-retardant epoxy resin nanocomposite based on molecular engineering of POSS","authors":"Cheng Liu ,&nbsp;Dongyang Zhuang ,&nbsp;Yan Zhou ,&nbsp;Jihua Liao ,&nbsp;Shengping Dai ,&nbsp;Changwang Pan ,&nbsp;Yuntong Li ,&nbsp;Lizong Dai ,&nbsp;Wei Wang","doi":"10.1016/j.polymertesting.2025.108719","DOIUrl":"10.1016/j.polymertesting.2025.108719","url":null,"abstract":"<div><div>The existing flame retardants are extensively utilized for epoxy resin (EP) in the field of engineering materials with good flame retardancy. Nevertheless, their introduction often brings a substantial decrease in mechanical properties of EP. To tackle this challenge, a multifunctional nano flame-retardant (PoDOH) that is designed to enhance both the flame-retardant and mechanical properties for EP simultaneously was synthesized in this study. The results demonstrate that for EP-10 %, its hardness increased by 34.8 %, and Young's modulus increased by 25.4 %, respectively, owing to the strong interfacial interaction among EP and PoDOH derived from the ring-opening reaction. Moreover, the synergistic action of the various flame retardant elements present in PoDOH imparts excellent flame retardancy to EP-10 % (V-0 rating, LOI = 32.6 % and PHRR decreased by 48.82 %). These findings indicate that PoDOH holds great potential as a versatile and efficient flame retardant for manufacturing high-performance EP.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108719"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of axial and shear mechanical response of PDMS elastomers and determination of Poisson's ratio using digital image correlation","authors":"Satya Pal,&nbsp;Abir Bhattacharyya","doi":"10.1016/j.polymertesting.2025.108687","DOIUrl":"10.1016/j.polymertesting.2025.108687","url":null,"abstract":"<div><div>Measurement of stress-strain response under different deformation modes is important for developing constitutive models of soft polymers. However, such measurements on soft and compliant polymers are challenging using traditional techniques due to generation of unwanted stress concentrations leading to premature failure during loading. In this study, a non-contact digital image correlation (DIC) technique along with a novel experimental setup were used to accurately measure the strain field on a specimen surface subjected to finite strain. Polydimethylsiloxane (PDMS) elastomers of three different base polymer to hardener ratio were characterized under three different deformation modes— uniaxial compression, uniaxial tension, and simple shear—over strain rates ranging between 10⁻³/s–10⁻¹/s. The resulting strain fields exhibited uniformity across all the deformation modes up to finite strains. While the lower strain rate experiments are minimally affected by strain acceleration and inertia effects, the specimens loaded under higher strain rate (10⁻¹/s) are initially affected by strain acceleration during loading, which precluded reliable determination of Young's moduli and shear moduli from the initial slope of the stress-strain responses. The Poisson's ratio calculated from the ratio between measured axial and lateral strains was close to 0.5 at small strains, and exhibited a close match with that calculated from Young's modulus (<em>E</em>) to shear modulus (<em>G</em>) ratio (<em>E/G),</em> validating linear elasticity theory at small strains. The tangent moduli for all the compositions were found to be practically strain-rate insensitive in the region of steady strain rate.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108687"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of thermoplastic polyurethane (TPU) and printing parameters on the thermal and mechanical performance of polylactic acid (PLA) / thermoplastic polyurethane (TPU) polymer","authors":"Muhammad Nafiz Hamidi,&nbsp;Jamaluddin Abdullah,&nbsp;Abdus Samad Mahmud,&nbsp;Muhammad Hafiz Hassan,&nbsp;Ahmad Yasier Zainoddin","doi":"10.1016/j.polymertesting.2025.108697","DOIUrl":"10.1016/j.polymertesting.2025.108697","url":null,"abstract":"<div><div>Polylactic acid (PLA) is a polymer widely used for 3D printing process owing to its mechanical properties which are high strength and flexural modulus and environmentally friendly. However, PLA is also a brittle polymer with low impact resistance. This weakness can be compensated by combining PLA with other polymer like Thermoplastic polyurethane (TPU) that is widely used to improve mechanical properties of PLA. In polymer 3D printing process, printing parameters affect the thermo-mechanical properties of the printed products. This study investigates the influence of TPU and various printing parameters on thermal and mechanical properties of PLA/TPU polymer blends. It provides more precise understanding on how each printing parameters and different TPU ratio affect the mechanical and thermal properties. It also helps in determining the significant parameters for better PLA/TPU blend print. This exploration of parameter effects adds novel insights, enhancing applicability in practical 3D printing processes. Six different TPU ratio was used which are 10 %–50 % by weight while the parameters being tested are printing speed, raster angle, layer thickness and printing temperature. The differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were conducted to assess the thermal properties while a tensile test was conducted to evaluate the mechanical properties. ANOVA analysis was employed for the data analysis. It was found that TPU altered the thermal properties of PLA by reducing the cold crystallization temperature, T_cc, enthalpy of crystallization, ΔH_c and enthalpy of melting, ΔH_m. The mechanical strength reduced by 64 % but the ductility improved up to 900 %. Based on ANOVA analysis, it can be concluded that influence of printing parameters on the mechanical properties are layer thickness &gt; printing speed &gt; raster angle &gt; printing temperature in descending order.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108697"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding the post-curing behaviors of polymethylacrylimide: Curing kinetics and molecular mobility","authors":"Yuan Chen ,&nbsp;Xiaolian Qiang ,&nbsp;Yaping Zhang ,&nbsp;Ningning Song ,&nbsp;Lixian Guo ,&nbsp;Siyuan Zhang ,&nbsp;Chunrong Tian ,&nbsp;Keping Chen","doi":"10.1016/j.polymertesting.2025.108720","DOIUrl":"10.1016/j.polymertesting.2025.108720","url":null,"abstract":"<div><div>In this study, the post-curing kinetic, molecular mobility and mechanical behavior of polymethylacrylimide (PMI), synthesized from methacrylic acid and methacrylonitrile, were systematically investigated. Differential scanning calorimetry results identified three distinct temperature zones during the post-curing process, which represented different types of curing reactions. Model-free kinetic methods were used to evaluate the post-curing kinetics of PMI materials. Fourier transform infrared spectroscopy demonstrated that the cyclization of anhydride groups predominantly occurred at lower post-curing temperatures, while the decomposition and transformation were observed at higher temperatures. Meanwhile, there was a progressive formation of imide rings with the increase of post-curing temperature. In addition, the molecular segment mobility of PMI materials was investigated via dielectric relaxation spectroscopy, and molecular segment mobility was gradually restricted during the post-curing process, indicated the formation of crosslinked network structure. Those changes of microstructures agreed well with the evolution of compressive properties. This study provides insights into the curing kinetics and structural evolution of PMI during post-curing process, offering guidance for optimizing post-curing conditions to achieve superior mechanical performance.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108720"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical performance of 3D-printed TPU auxetic structures for energy absorption applications","authors":"Sergio Fuentes del Toro ,&nbsp;Jorge Crespo-Sanchez ,&nbsp;Jorge Ayllón ,&nbsp;Alvaro Rodríguez-Prieto ,&nbsp;Ana María Camacho","doi":"10.1016/j.polymertesting.2024.108669","DOIUrl":"10.1016/j.polymertesting.2024.108669","url":null,"abstract":"<div><div>The emergence of metamaterials and layered structures obtained through additive manufacturing (AM) techniques opens a new paradigm of mechanical properties for advanced applications that need to be explored. This study investigates the mechanical behavior of 3D-printed auxetic structures, fabricated from thermoplastic polyurethane (TPU), under tensile and compressive loads. Utilizing fused deposition modeling (MEX), we examined the influence of printing direction on the anisotropic mechanical properties of TPU, with a particular focus on energy absorption, stress–strain responses, and damping capabilities. The research employs the Ogden model for hyperelastic characterization, demonstrating excellent correlation with experimental data. Thus, the novelty of this work relies on an approach that – with a focus in the precision and accuracy of the mechanical performance assessment – through a robust novel methodology combining the Ogden’s analytical model with numerical simulation provided by Ansys® and experimental tests of tensile and compression allows to comprehensively understand the mechanical performance of novel auxetic structures intended to energy absorption and impact resistance applications. Our findings reveal significant variations in mechanical performance based on printing orientation, with the 0°direction offering superior ductility and strength. These results suggest that optimizing the printing direction is crucial for enhancing the performance of TPU auxetic structures, particularly in applications requiring high impact resistance, energy absorption, and damping. This study contributes to the advancement of 3D printing technology for the development of next-generation materials with potential applications in protective gear, medical devices or damping devices, among others.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108669"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Facile grafting method achieves Unprecedented dispersion stability of carbon black in PP fiber","authors":"Yaoming Wang ,&nbsp;Guihao Liu ,&nbsp;Yuqing Liu ,&nbsp;Yiqing Zhang ,&nbsp;Guangtao Chang ,&nbsp;Ruoxin Li","doi":"10.1016/j.polymertesting.2025.108698","DOIUrl":"10.1016/j.polymertesting.2025.108698","url":null,"abstract":"<div><div>Carbon black (CB) offers valuable properties, but its tendency to agglomerate hinders its full potential in polymer applications. This study presents a novel and straightforward graft modification method to overcome this limitation. By covalently bonding organic functional groups to the CB surface, the surface energy of carbon black was significantly reduced and enhanced its compatibility with organic PP polymers. Characterization techniques (FTIR, XPS, Raman, TGA, etc.) confirm successful grafting and demonstrate excellent dispersion stability of modified CB in organic media. The modified CB exhibits uniform dispersion and reduced particle size within polypropylene (PP) fibers, leading to tensile strength increased dramatically from 103 MPa (unmodified) to 517 MPa (modified). Moreover, the strain reached 1086 %, exceeding both unmodified CB or commercial CB concentrate modified polypropylene (PP) fibers by 31 % and 11 %, respectively. This method represents a significant advancement over existing techniques by providing a straightforward and efficient approach to developing high-strength polypropylene fibers with exceptional tensile and strain characteristics for coloring synthetic fiber applications.</div></div>","PeriodicalId":20628,"journal":{"name":"Polymer Testing","volume":"143 ","pages":"Article 108698"},"PeriodicalIF":5.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}