This study is concerned with the stability analysis for various vibrational motions of tow-steered variable angle fibres based composite rotating beam with time varying speed. The formulation combines a higher order theory introducing sine function along with finite element methodology. It satisfies the plane stress condition in width direction of beam. The displacement kinematics are generic in the sense it includes various possible vibrational motions like chord and flap wise motions, torsional and axial vibration behaviours. The equilibrium equations for the proposed problem evolved adopting virtual dynamic work are then transformed into the equations of Mathieu-Hill type considering time varying harmonic rotational speed. Using Bolotin’s procedure coupled with C1 continuity-based beam element, the parametric resonance zones along with boundary limits are numerically evaluated. The eigenvalue type of solution methodology applied for the detailed study is validated for accuracy and computational efficiency against the time domain dynamic response analysis. Based on in-depth analysis, dynamic instability characteristics in terms of resonance range and origin of instability of composite beam subjected to the chord and flap wise, torsional and axial motions are studied considering curvilinear fibre path angles, beam cross section, hub radius, thickness ratio and mean rotary speed.
{"title":"Variable angle tow-steered fibres based rotating composite beam with rotary oscillations – Parametric excitation/instability analysis","authors":"Mohamed Haboussi, Girolamo Di Cara, Sudarshan Naik, Olivier Polit, Ganapathi Manickam","doi":"10.1177/07316844241272952","DOIUrl":"https://doi.org/10.1177/07316844241272952","url":null,"abstract":"This study is concerned with the stability analysis for various vibrational motions of tow-steered variable angle fibres based composite rotating beam with time varying speed. The formulation combines a higher order theory introducing sine function along with finite element methodology. It satisfies the plane stress condition in width direction of beam. The displacement kinematics are generic in the sense it includes various possible vibrational motions like chord and flap wise motions, torsional and axial vibration behaviours. The equilibrium equations for the proposed problem evolved adopting virtual dynamic work are then transformed into the equations of Mathieu-Hill type considering time varying harmonic rotational speed. Using Bolotin’s procedure coupled with C<jats:sup>1</jats:sup> continuity-based beam element, the parametric resonance zones along with boundary limits are numerically evaluated. The eigenvalue type of solution methodology applied for the detailed study is validated for accuracy and computational efficiency against the time domain dynamic response analysis. Based on in-depth analysis, dynamic instability characteristics in terms of resonance range and origin of instability of composite beam subjected to the chord and flap wise, torsional and axial motions are studied considering curvilinear fibre path angles, beam cross section, hub radius, thickness ratio and mean rotary speed.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"22 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the field of aerospace, the application of carbon fiber composite parts is increasing year by year. As an important factor in the manufacturing of composite parts, tools play a crucial role in the manufacturing accuracy of composite parts, and composite tools have higher accuracy to better meet the manufacturing requirements. In this study, the properties of the novel thermoplastic composite mandrel of the new polymethyl methacrylate matrix are further investigated and a model is proposed to simulate the curing and spring back process of the composite part with the proposed composite mandrel. In detail, the glass transition temperature test and dynamic frequency test were carried out for the thermoplastic composite mandrel. The material constitutive equation of the thermoplastic composite mandrel was constructed based on the experimental data, and the accuracy of the constitutive equation of thermoplastic matrix material was verified by tensile experiments of matrix materials under constant strain conditions. Finally, the simulation result is compared with the fabricated part, and the effectiveness of the proposed method has been verified. This proved that the developed constitutive model of thermoplastic composite mandrel can effectively predict the curing deformation of composite parts with complex structures.
{"title":"Experimental and numerical analysis of new thermoplastic composite mandrels","authors":"Siyu Chen, Longfei Cai, Xin Zhang, Xishuang Jing, Chengyang Zhang","doi":"10.1177/07316844241278529","DOIUrl":"https://doi.org/10.1177/07316844241278529","url":null,"abstract":"In the field of aerospace, the application of carbon fiber composite parts is increasing year by year. As an important factor in the manufacturing of composite parts, tools play a crucial role in the manufacturing accuracy of composite parts, and composite tools have higher accuracy to better meet the manufacturing requirements. In this study, the properties of the novel thermoplastic composite mandrel of the new polymethyl methacrylate matrix are further investigated and a model is proposed to simulate the curing and spring back process of the composite part with the proposed composite mandrel. In detail, the glass transition temperature test and dynamic frequency test were carried out for the thermoplastic composite mandrel. The material constitutive equation of the thermoplastic composite mandrel was constructed based on the experimental data, and the accuracy of the constitutive equation of thermoplastic matrix material was verified by tensile experiments of matrix materials under constant strain conditions. Finally, the simulation result is compared with the fabricated part, and the effectiveness of the proposed method has been verified. This proved that the developed constitutive model of thermoplastic composite mandrel can effectively predict the curing deformation of composite parts with complex structures.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"19 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Traditional prosthetic sockets often consist of thermoplastic and wood-based materials. However, these sockets are known to be uncomfortable, heavy, and economically challenging. Natural fibers are quickly adapting and becoming more popular because of their biodegradable, long-lasting, and biocompatible nature. They are replacing synthetic fibers in the design and development of structural parts. This research looked into a new hybrid composite made of natural and synthetic fibers (basalt, jute, and carbon) that are reinforced in a polyester thermoset based matrix. The performance of this hybrid composite was then compared to that of pristine or single fiber-reinforced composites manufactured using woven jute, basalt, and carbon. The samples were manufactured using the vacuum-assisted resin transfer molding technique and cured at room temperature. The samples were then subjected to flexure and impact tests. The hybrid composite had an impact strength of 46.71 kJ/m2, higher than all other single fiber combinations. The flexural strength of the hybrid composite was determined to be 66.25 MPa, matching that of basalt fiber and surpassing that of other conventional single fiber composite laminates. Fractographic analysis has revealed that the main cause of failure in flexure is mostly attributed to delamination and fiber micro-buckling. Although hybrid reinforced composites had superior performance in terms of both impact and flexure strength, basalt fibers demonstrated comparable strength, specifically in flexure. Overall, the hybrid composite possesses exceptional promise for use in prosthetic construction.
{"title":"Comparison of single- and hybrid-fiber composite laminates for use in prosthetic sockets","authors":"Ayesha Naseem, Syeda Husna Nazakat, Mohsin Saleem, Suhail Hyder Vattathurvalappil, Abrar H Baluch","doi":"10.1177/07316844241279700","DOIUrl":"https://doi.org/10.1177/07316844241279700","url":null,"abstract":"Traditional prosthetic sockets often consist of thermoplastic and wood-based materials. However, these sockets are known to be uncomfortable, heavy, and economically challenging. Natural fibers are quickly adapting and becoming more popular because of their biodegradable, long-lasting, and biocompatible nature. They are replacing synthetic fibers in the design and development of structural parts. This research looked into a new hybrid composite made of natural and synthetic fibers (basalt, jute, and carbon) that are reinforced in a polyester thermoset based matrix. The performance of this hybrid composite was then compared to that of pristine or single fiber-reinforced composites manufactured using woven jute, basalt, and carbon. The samples were manufactured using the vacuum-assisted resin transfer molding technique and cured at room temperature. The samples were then subjected to flexure and impact tests. The hybrid composite had an impact strength of 46.71 kJ/m<jats:sup>2</jats:sup>, higher than all other single fiber combinations. The flexural strength of the hybrid composite was determined to be 66.25 MPa, matching that of basalt fiber and surpassing that of other conventional single fiber composite laminates. Fractographic analysis has revealed that the main cause of failure in flexure is mostly attributed to delamination and fiber micro-buckling. Although hybrid reinforced composites had superior performance in terms of both impact and flexure strength, basalt fibers demonstrated comparable strength, specifically in flexure. Overall, the hybrid composite possesses exceptional promise for use in prosthetic construction.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"75 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-07DOI: 10.1177/07316844241278045
Francis T Omigbodun, Bankole I Oladapo, Norman Osa-uwagboe
This review research investigates the potential of Polylactic Acid (PLA)/Hydroxyapatite (HA) composites in bone regeneration, focusing on the composites’ synthesis methods, mechanical properties, and biocompatibility. Through an extensive examination of various preparation techniques, such as solvent evaporation, phase separation, electrospinning, and lyophilisation, the study assesses how these methods influence the physical and biological properties of PLA/HA composites. Significant findings from the review highlight that PLA/HA composites enhance osteoblast activity and proliferation, demonstrating an increase in cell adhesion by up to 25% compared to PLA alone. These composites substantially improve mechanical properties, increasing compressive strength and fracture toughness by approximately 30% and 50%, respectively. These enhancements are pivotal for applications requiring robust, load-bearing materials supporting bone tissue integration and regeneration. In conclusion, due to their optimised mechanical strength, biodegradability, and bioactivity, PLA/HA composites are promising biomaterials for orthopaedic and dental applications. The review suggests future research directions focused on long-term clinical outcomes and further material refinement to maximise clinical efficacy and patient compatibility.
{"title":"Exploring the frontier of Polylactic Acid/Hydroxyapatite composites in bone regeneration and their revolutionary biomedical applications – A review","authors":"Francis T Omigbodun, Bankole I Oladapo, Norman Osa-uwagboe","doi":"10.1177/07316844241278045","DOIUrl":"https://doi.org/10.1177/07316844241278045","url":null,"abstract":"This review research investigates the potential of Polylactic Acid (PLA)/Hydroxyapatite (HA) composites in bone regeneration, focusing on the composites’ synthesis methods, mechanical properties, and biocompatibility. Through an extensive examination of various preparation techniques, such as solvent evaporation, phase separation, electrospinning, and lyophilisation, the study assesses how these methods influence the physical and biological properties of PLA/HA composites. Significant findings from the review highlight that PLA/HA composites enhance osteoblast activity and proliferation, demonstrating an increase in cell adhesion by up to 25% compared to PLA alone. These composites substantially improve mechanical properties, increasing compressive strength and fracture toughness by approximately 30% and 50%, respectively. These enhancements are pivotal for applications requiring robust, load-bearing materials supporting bone tissue integration and regeneration. In conclusion, due to their optimised mechanical strength, biodegradability, and bioactivity, PLA/HA composites are promising biomaterials for orthopaedic and dental applications. The review suggests future research directions focused on long-term clinical outcomes and further material refinement to maximise clinical efficacy and patient compatibility.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"40 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-05DOI: 10.1177/07316844241279685
Esmail Sharifzadeh, Fiona Ader, Golshan Moradi
In this study, the polymer/particle interphase region, formed around dispersed and clustered nanoparticles, was represented and evaluated using a novel multi-layer structural model. The physical/mechanical characteristics of each layer were determined by a developed form of De Gennes’s scaling theory. The time-dependent creep behavior of the interphase region was studied by incorporating Burger viscoelastic model into a specifically designed equivalent box model (EBM) with a layered structure. The content and size of clusters were estimated using a specifically developed mechanical model, based on the concept of micro-scale excluded volumes. The overall creep behavior of the polymer nanocomposites was then predicted considering the interaction of the polymer matrix, interphase region, dispersed and aggregated/agglomerated nanoparticle domains (prediction error <5%). The theoretical results were benchmarked against the actual data, obtained from creep and tensile tests, in order to verify the accuracy of the model as well as the applied primary concepts.
在本研究中,使用一种新型多层结构模型表示和评估了分散和聚集纳米粒子周围形成的聚合物/粒子相间区域。各层的物理/机械特性由 De Gennes 缩放理论的发展形式确定。通过将汉堡粘弹性模型纳入专门设计的具有分层结构的等效盒模型(EBM),研究了相间区域随时间变化的蠕变行为。根据微尺度排除体积的概念,使用专门开发的力学模型估算了团聚体的含量和大小。然后,考虑到聚合物基体、相间区域、分散纳米粒子域和聚集/团聚纳米粒子域之间的相互作用,对聚合物纳米复合材料的整体蠕变行为进行了预测(预测误差为 5%)。理论结果与从蠕变和拉伸试验中获得的实际数据进行了比对,以验证模型的准确性和应用的基本概念。
{"title":"Multi-layer structural representation of polymer/particle interphase region based on De Gennes’s scaling theory","authors":"Esmail Sharifzadeh, Fiona Ader, Golshan Moradi","doi":"10.1177/07316844241279685","DOIUrl":"https://doi.org/10.1177/07316844241279685","url":null,"abstract":"In this study, the polymer/particle interphase region, formed around dispersed and clustered nanoparticles, was represented and evaluated using a novel multi-layer structural model. The physical/mechanical characteristics of each layer were determined by a developed form of De Gennes’s scaling theory. The time-dependent creep behavior of the interphase region was studied by incorporating Burger viscoelastic model into a specifically designed equivalent box model (EBM) with a layered structure. The content and size of clusters were estimated using a specifically developed mechanical model, based on the concept of micro-scale excluded volumes. The overall creep behavior of the polymer nanocomposites was then predicted considering the interaction of the polymer matrix, interphase region, dispersed and aggregated/agglomerated nanoparticle domains (prediction error <5%). The theoretical results were benchmarked against the actual data, obtained from creep and tensile tests, in order to verify the accuracy of the model as well as the applied primary concepts.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"12 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-05DOI: 10.1177/07316844241281658
Guilherme F Gonçalves, Guillaume dos Reis, Luís FMF Rodrigues, Paulo RF Rocha, Sofia C. Martins, Tiago M Diogo, Marcelo FSF de Moura, Mário AP Vaz, Raul D Ferreira Moreira
In recent years, the development of adhesive repair in composites has been considered as crucial, as it not only prolongs the service life and fortifies structural resilience but also addresses environmental concerns by restoring and reinforcing composite components across diverse sectors, such as the aeronautic and automotive industries. This study presents a numerical analysis with cohesive zone modelling of adhesively bonded repairs of carbon fibre reinforced polymers with overplies using an epoxy adhesive and provides insights into optimising repairs for such components. The study focuses on two repair geometries: Scarf and Two-Stepped, considering variables such as overlap and reinforcement lengths, and its position when subjected to tensile and three-point bending loading. The results show that the introduction of external reinforcements (overplies) significantly increases the mechanical strength of the repaired joints, resulting in substantial improvements in the failure load for both geometries and both loading conditions. Under tension conditions, the Stepped repair generally obtained better strength than the Scarf geometry. On the other hand, when subject to bending, Scarf repair strength increases considerably in comparison to the Stepped geometry. The failure analysis provides further insights into the failure paths of Scarf and Step repairs.
{"title":"Improving the performance of Scarf and Step adhesive repairs with external reinforcements in composite structures","authors":"Guilherme F Gonçalves, Guillaume dos Reis, Luís FMF Rodrigues, Paulo RF Rocha, Sofia C. Martins, Tiago M Diogo, Marcelo FSF de Moura, Mário AP Vaz, Raul D Ferreira Moreira","doi":"10.1177/07316844241281658","DOIUrl":"https://doi.org/10.1177/07316844241281658","url":null,"abstract":"In recent years, the development of adhesive repair in composites has been considered as crucial, as it not only prolongs the service life and fortifies structural resilience but also addresses environmental concerns by restoring and reinforcing composite components across diverse sectors, such as the aeronautic and automotive industries. This study presents a numerical analysis with cohesive zone modelling of adhesively bonded repairs of carbon fibre reinforced polymers with overplies using an epoxy adhesive and provides insights into optimising repairs for such components. The study focuses on two repair geometries: Scarf and Two-Stepped, considering variables such as overlap and reinforcement lengths, and its position when subjected to tensile and three-point bending loading. The results show that the introduction of external reinforcements (overplies) significantly increases the mechanical strength of the repaired joints, resulting in substantial improvements in the failure load for both geometries and both loading conditions. Under tension conditions, the Stepped repair generally obtained better strength than the Scarf geometry. On the other hand, when subject to bending, Scarf repair strength increases considerably in comparison to the Stepped geometry. The failure analysis provides further insights into the failure paths of Scarf and Step repairs.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"23 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1177/07316844241279699
Rodrigo Ramírez-Aguilar, Cecilia Zárate-Pérez, E. A. Franco-Urquiza
The aerospace sector uses butyl rubber to manufacture carbon fiber components through an autoclave or infusion. Both manufacturing techniques require a high vacuum to achieve adequate impregnation of the carbon fiber fabrics with epoxy resin, and butyl rubber is used as the sealant. The aerospace sector discontinues materials with shelf life expired, and butyl rubber is one of the materials most discontinued for not being used within the designated time. This work presents the development of composites using polypropylene and discontinued butyl tape. Composites with 30, 50, and 70 wt% of butyl rubber content were prepared using a twin-screw extruder. The structural analysis showed that the composites with 50 wt% and 70 wt% are similar to butyl rubber, while the compound with 30 wt% of butyl is similar to polypropylene. The degree of crystallinity of the compound with 50 wt% of butyl content was 18% higher than the PP, and the melting temperature decreased by 30% with the higher butyl content. SSA revealed that the highest enthalpic contribution occurred in the crystalline fraction of higher perfection, except for the compound with 50 wt% of butyl content, whose less perfect crystalline populations grew at the expense of the most perfect crystals. The reduction of the crystalline fraction implies that butyl interferes with the formation of crystals, developing populations with lower lamellar thickness that favors the overall crystallinity of the compound. Young’s modulus, yield strength, and nominal strain decreased with butyl rubber content. The composites showed rough failure surfaces with solid butyl rubber particles and poor adhesion to polypropylene. Butyl particles with diverse sizes and geometries lead to sudden failure of the composites and high dispersion in strain values.
{"title":"Successive self-nucleation and Annealing technique applied to polypropylene/butyl rubber composites: Recycling alternatives for vacuum bagging materials","authors":"Rodrigo Ramírez-Aguilar, Cecilia Zárate-Pérez, E. A. Franco-Urquiza","doi":"10.1177/07316844241279699","DOIUrl":"https://doi.org/10.1177/07316844241279699","url":null,"abstract":"The aerospace sector uses butyl rubber to manufacture carbon fiber components through an autoclave or infusion. Both manufacturing techniques require a high vacuum to achieve adequate impregnation of the carbon fiber fabrics with epoxy resin, and butyl rubber is used as the sealant. The aerospace sector discontinues materials with shelf life expired, and butyl rubber is one of the materials most discontinued for not being used within the designated time. This work presents the development of composites using polypropylene and discontinued butyl tape. Composites with 30, 50, and 70 wt% of butyl rubber content were prepared using a twin-screw extruder. The structural analysis showed that the composites with 50 wt% and 70 wt% are similar to butyl rubber, while the compound with 30 wt% of butyl is similar to polypropylene. The degree of crystallinity of the compound with 50 wt% of butyl content was 18% higher than the PP, and the melting temperature decreased by 30% with the higher butyl content. SSA revealed that the highest enthalpic contribution occurred in the crystalline fraction of higher perfection, except for the compound with 50 wt% of butyl content, whose less perfect crystalline populations grew at the expense of the most perfect crystals. The reduction of the crystalline fraction implies that butyl interferes with the formation of crystals, developing populations with lower lamellar thickness that favors the overall crystallinity of the compound. Young’s modulus, yield strength, and nominal strain decreased with butyl rubber content. The composites showed rough failure surfaces with solid butyl rubber particles and poor adhesion to polypropylene. Butyl particles with diverse sizes and geometries lead to sudden failure of the composites and high dispersion in strain values.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"63 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-30DOI: 10.1177/07316844241278136
Zihan Zhao, Lingyu Meng, Xiangrui Li, Chunfeng Li, Lei Le, Mingli Liu
In the present work, corn straw/polypropylene/modified ammonium polyphosphate composites (CS/PP/KAPP) were prepared by employing melt blending and hot-pressing methods. Due to the high production cost of KAPP and the fact that a large amount of KAPP can reduce the mechanical properties of wood plastic composite (WPC), natural minerals were used to replace some of KAPP to improve the flame retardancy. The results showed that, for all the studied groups, when the amount of ultrafine montmorillonite was 8.6 wt%, the flame retardancy of the co-effective flame retardant was better than that of the pure KAPP group. Meanwhile, the obtained oxygen index of the composite was 30.2%, with a vertical combustion class of V-0. In the other groups, the ultimate oxygen indices of the composites were lower than that of the pure KAPP group due to the reduced content of KAPP. The results showed that the three co-effective flame retardants formed a dense carbon layer during combustion. This enhanced the rate of formation of carbon and reduced the release of smoke and carbon monoxide. In addition, the three natural minerals were found to play a good filling role, enhancing the mechanical properties of the composites, improving their thermal stability, and reducing their rates of absorption of water.
{"title":"Performance study of modified ammonium polyphosphate/natural mineral synergistic flame retardant corn straw/polypropylene composites","authors":"Zihan Zhao, Lingyu Meng, Xiangrui Li, Chunfeng Li, Lei Le, Mingli Liu","doi":"10.1177/07316844241278136","DOIUrl":"https://doi.org/10.1177/07316844241278136","url":null,"abstract":"In the present work, corn straw/polypropylene/modified ammonium polyphosphate composites (CS/PP/KAPP) were prepared by employing melt blending and hot-pressing methods. Due to the high production cost of KAPP and the fact that a large amount of KAPP can reduce the mechanical properties of wood plastic composite (WPC), natural minerals were used to replace some of KAPP to improve the flame retardancy. The results showed that, for all the studied groups, when the amount of ultrafine montmorillonite was 8.6 wt%, the flame retardancy of the co-effective flame retardant was better than that of the pure KAPP group. Meanwhile, the obtained oxygen index of the composite was 30.2%, with a vertical combustion class of V-0. In the other groups, the ultimate oxygen indices of the composites were lower than that of the pure KAPP group due to the reduced content of KAPP. The results showed that the three co-effective flame retardants formed a dense carbon layer during combustion. This enhanced the rate of formation of carbon and reduced the release of smoke and carbon monoxide. In addition, the three natural minerals were found to play a good filling role, enhancing the mechanical properties of the composites, improving their thermal stability, and reducing their rates of absorption of water.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"122 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.1177/07316844241279013
Umang Dubey, Panneerselvam K
Firms choose to maximize the use of natural resources when producing new generations of polymer composites. The incorporation of carbon-based nanoparticles into the polymer matrix resulted in substantial enhancements in strength qualities. In this work, a set of bio-nanocomposites was fabricated using reduced graphene oxide (rGO) at several weight %s (0, 0.25, 0.5, 0.75, and 1 wt.%) in a bio-blended epoxy thermoset matrix generated from adding cashew nut shell liquid (CNSL) as an additive in a commercial grade bisphenol-A-based unmodified liquid epoxy resin. Thermal and mechanical properties, morphology analysis, XRD analysis, flammability, and limiting oxygen index (LOI) were used for characterization. The mechanical properties of the bio-nanocomposite containing 0.75 wt.% of rGO were investigated, resulting in the observation of enhanced flexural strength by 43.97%, compression strength by 58.08%, tensile strength by 39.84%, impact energy by 47.05%, and shore-D hardness by 21.26% compared to neat epoxy. The thermal stability of a bio-nanocomposite containing 0.75 wt.% of rGO is not compromised while demonstrating a 44.71 % residual mass at 550°C compared to neat epoxy. The cured bio-blended epoxy has a 23.38% lower combustion rate than epoxy resin and shows slow burning rate.
{"title":"Low-combustible, high-strength, and thermally stable bio-blended epoxy-based bio-nanocomposite using reduced graphene oxide as a strengthening agent","authors":"Umang Dubey, Panneerselvam K","doi":"10.1177/07316844241279013","DOIUrl":"https://doi.org/10.1177/07316844241279013","url":null,"abstract":"Firms choose to maximize the use of natural resources when producing new generations of polymer composites. The incorporation of carbon-based nanoparticles into the polymer matrix resulted in substantial enhancements in strength qualities. In this work, a set of bio-nanocomposites was fabricated using reduced graphene oxide (rGO) at several weight %s (0, 0.25, 0.5, 0.75, and 1 wt.%) in a bio-blended epoxy thermoset matrix generated from adding cashew nut shell liquid (CNSL) as an additive in a commercial grade bisphenol-A-based unmodified liquid epoxy resin. Thermal and mechanical properties, morphology analysis, XRD analysis, flammability, and limiting oxygen index (LOI) were used for characterization. The mechanical properties of the bio-nanocomposite containing 0.75 wt.% of rGO were investigated, resulting in the observation of enhanced flexural strength by 43.97%, compression strength by 58.08%, tensile strength by 39.84%, impact energy by 47.05%, and shore-D hardness by 21.26% compared to neat epoxy. The thermal stability of a bio-nanocomposite containing 0.75 wt.% of rGO is not compromised while demonstrating a 44.71 % residual mass at 550°C compared to neat epoxy. The cured bio-blended epoxy has a 23.38% lower combustion rate than epoxy resin and shows slow burning rate.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"26 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The NOL ring is employed as a specimen to examine the properties of filament-wound composites, with its winding tension playing a pivotal role in determining the performance of the resultant wound products. Traditional methods used for modeling the winding process have several disadvantages, including inaccuracies in setting the tension and difficulties in controlling the thickness of the wound layers. To address these limitations, utilizing the response mechanism of the tracking element method, a precise three-dimensional (3D) winding finite element model of the NOL ring is constructed. Adopting a wireless film pressure testing system to dynamically measure interlayer pressures, improved the precision of our experimental results by decoupling factors affecting tension relaxation and focusing on the structural relaxation characteristics of winding tension in composite materials. Experimental results demonstrate that, using this model, the prediction error for the radial stress on the mandrel surface is only 6.03%, which is substantially lower than that of the conventional models (16.72%). In addition, the model is used to investigate the stress transfer mechanisms in the radial/circumferential directions of the winding layers on a macroscopic scale. Finally, it is demonstrated through examples that this model can also achieve equal residual tension through optimization, which is expected to improve the structural efficiency of wound products.
{"title":"Tension relaxation during the NOL ring winding process based on a novel tracking element method","authors":"Xin Xie, Ximing Xie, Hongyin Li, Liangliang Shen, Jun Zhu, Haitao Yu, Jianbo Tang, Jian Xu","doi":"10.1177/07316844241278554","DOIUrl":"https://doi.org/10.1177/07316844241278554","url":null,"abstract":"The NOL ring is employed as a specimen to examine the properties of filament-wound composites, with its winding tension playing a pivotal role in determining the performance of the resultant wound products. Traditional methods used for modeling the winding process have several disadvantages, including inaccuracies in setting the tension and difficulties in controlling the thickness of the wound layers. To address these limitations, utilizing the response mechanism of the tracking element method, a precise three-dimensional (3D) winding finite element model of the NOL ring is constructed. Adopting a wireless film pressure testing system to dynamically measure interlayer pressures, improved the precision of our experimental results by decoupling factors affecting tension relaxation and focusing on the structural relaxation characteristics of winding tension in composite materials. Experimental results demonstrate that, using this model, the prediction error for the radial stress on the mandrel surface is only 6.03%, which is substantially lower than that of the conventional models (16.72%). In addition, the model is used to investigate the stress transfer mechanisms in the radial/circumferential directions of the winding layers on a macroscopic scale. Finally, it is demonstrated through examples that this model can also achieve equal residual tension through optimization, which is expected to improve the structural efficiency of wound products.","PeriodicalId":16943,"journal":{"name":"Journal of Reinforced Plastics and Composites","volume":"59 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}