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Srinivasan DV, Vassilopoulos AP. Fatigue dataset of hybrid non-toughened and toughened epoxy adhesives. Data Brief 2024; 52:109862. [PMID: 38146307 PMCID: PMC10749227 DOI: 10.1016/j.dib.2023.109862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/10/2023] [Accepted: 11/22/2023] [Indexed: 12/27/2023] Open
Abstract
In this article, four different structural epoxy adhesives such as SPABOND™ 820HTA (non-toughened), SPABOND™ 840HTA (toughened) adhesives, and their two hybrid combinations are fabricated using a manual mixing method. Quasi-static tensile experiments are conducted at standardized and high strain rates using ASTM D638-22 Type II specimens to investigate the strain rate effects on the tensile properties. Tensile-tensile fatigue experiments are performed using ASTM D638-22 Type I and Type II specimens to evaluate the impact of specimen geometry and toughening on fatigue life. The digital image correlation technique is utilized to obtain full-field strain data in these experiments. Technical data analysis, plotting, smoothing, filtering, and averaging are carried out using Origin ProⓇ and MATLAB R2021bⓇ. The obtained S-N curve data can be used to develop fatigue failure criteria and predict the behavior of wind turbine blade adhesive joints through finite element modeling.
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Affiliation(s)
- Dharun Vadugappatty Srinivasan
- Composite Construction Laboratory (CCLab), Station 16, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
| | - Anastasios P. Vassilopoulos
- Composite Construction Laboratory (CCLab), Station 16, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
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Xie T, Lv X, Tian S, Zhang X, Lv Z, Sun S. Tailored chitosan-based entrapped catalyst for dyes removal by highly active, stable, and recyclable nanoparticles toughened hydrogel. Int J Biol Macromol 2023:125634. [PMID: 37399876 DOI: 10.1016/j.ijbiomac.2023.125634] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/22/2023] [Accepted: 06/28/2023] [Indexed: 07/05/2023]
Abstract
Functional catalytic hydrogels were a promising catalyst carrier with the advantages of low cost, high efficiency and environmental friendliness. However, conventional hydrogels suffered from mechanical defects and brittleness. Acrylamide (AM) and lauryl methacrylate (LMA) were used as raw materials, SiO2-NH2 spheres as toughening agents, and chitosan (CS) as stabilizers to form hydrophobic binding networks. p(AM/LMA)/SiO2-NH2/CS hydrogels exhibited superior stretchability and withstood strains up to 14,000 %. In addition, these hydrogels exhibited exceptional mechanical properties, including a tensile strength of 213 kPa and a toughness of 13.1 MJ/m3. Surprisingly, the introduction of chitosan into hydrogels showed excellent antibacterial activity against S. aureus and E. coli. At the same time, the hydrogel served as a template for the formation of Au nanoparticles. This resulted in high catalytic activity for methylene blue (MB) and Congo red (CR) on p(AM/LMA)/SiO2-NH2/CS-8 %-Au hydrogels with Kapp of 1.038 and 0.76 min-1, respectively. The catalyst was also found to be reusable for 10 cycles while maintaining an efficiency of over 90 %. Therefore, innovative design strategies can be used to develop durable and scalable hydrogel materials for catalysis in the wastewater treatment industry.
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Affiliation(s)
- Ting Xie
- School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China; Engineering Research Center of Synthetic Resin and Special Fiber, Ministry of Education, Changchun University of Technology, Changchun 130012, China
| | - Xue Lv
- School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China; Engineering Research Center of Synthetic Resin and Special Fiber, Ministry of Education, Changchun University of Technology, Changchun 130012, China.
| | - Song Tian
- School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China; Engineering Research Center of Synthetic Resin and Special Fiber, Ministry of Education, Changchun University of Technology, Changchun 130012, China
| | - Xikun Zhang
- School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China; Engineering Research Center of Synthetic Resin and Special Fiber, Ministry of Education, Changchun University of Technology, Changchun 130012, China
| | - Ziwei Lv
- School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China; Engineering Research Center of Synthetic Resin and Special Fiber, Ministry of Education, Changchun University of Technology, Changchun 130012, China
| | - Shulin Sun
- School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China; Engineering Research Center of Synthetic Resin and Special Fiber, Ministry of Education, Changchun University of Technology, Changchun 130012, China
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Liu H, Zhao Y, Zheng Y, Chen J, Wang J, Gao G, Bai D. Toward ultra-tough and heat-resistant biodegradable polylactide/core-shell rubber blends by regulating the distribution of rubber particles with stereocomplex crystallites. Int J Biol Macromol 2023; 232:123422. [PMID: 36708887 DOI: 10.1016/j.ijbiomac.2023.123422] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/17/2023] [Accepted: 01/21/2023] [Indexed: 01/26/2023]
Abstract
Ultra-tough and heat-resistant poly(l-lactide)/core-shell rubber (PLLA/CSR) blends were fabricated by utilizing stereocomplex (SC) crystallites to effectively regulate the CSR distribution in PLLA matrix. Linear and 3-11 armed poly(d-lactide)s (PDLAs) were synthesized and then melt-mixed with PLLA/CSR blend. Interestingly, the incorporated PDLA chains could collaborate with PLLA chains to form dense SC crystallites network in PLLA/PDLA/CSR blends, thus inducing the CSR particles to transform from uniform distribution structure to network-like structure. With increasing the PDLA arm numbers, the size of CSR clusters in the network-like structure first increased and then decreased, and the continuity of the network-like structure first remained at a high level and then decreased obviously. The formation of CSR network-like structure could remarkably improve the impact strength of PLLA/PDLA/CSR blends without deteriorating their strength and modulus (compared with PLLA/CSR blend), and the CSR network-like structure with larger-sized CSR clusters and higher continuity could help obtain higher impact strength (78.3 kJ/m2). Moreover, the heat resistance of PLLA/PDLA/CSR blends could also be significantly improved (the highest Vicat softening temperature was 131 °C) by the SC crystallites network and CSR network-like structure. This work provides an effective strategy for controlling the rubber network-like morphology and thereby preparing high-performance PLLA materials.
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Affiliation(s)
- Huili Liu
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Yaling Zhao
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Yushan Zheng
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Jianyang Chen
- Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China
| | - Jianchuan Wang
- School of Chemistry & Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Guangyong Gao
- SWS Hemodialysis Care Co., Ltd, Chongqing, Chongqing 401120, China
| | - Dongyu Bai
- Chongqing Key Laboratory of Materials Surface & Interface Science, School of Materials Science and Engineering, Chongqing University of Arts and Sciences, Chongqing 402160, China.
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Srinivasan DV, Vassilopoulos AP. Dataset for the hybrid non-toughened and toughened epoxy adhesive properties. Data Brief 2023; 47:108912. [PMID: 36747976 PMCID: PMC9898622 DOI: 10.1016/j.dib.2023.108912] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/09/2023] [Accepted: 01/11/2023] [Indexed: 01/19/2023] Open
Abstract
In this article, the manufacturing and toughening effects on the material properties of epoxy adhesives used in wind turbine rotor blades are presented. Different adhesive materials are developed by combining SPABOND™ 820HTA (non-toughened) and SPABOND™ 840HTA (toughened) adhesives with the machine and manual mixing methods. Firstly, the manufacturing quality are compared between the two methods, in terms of void percentage and void volume using micro-computed tomography. Dynamical Mechanical analysis, uniaxial tensile testing, V-notch shear testing and single-edge-notch beam testing are carried out to evaluate the manufacturing and toughening effects. In these experiments, the digital image correlation technique is exploited to obtain the displacement and strain data. Origin ProⓇ and MATLAB R2021bⓇ are utilized for technical data analysis, plotting, smoothing, filtering, and averaging. The obtained data could be used to select the adhesive material based on the strength and stiffness requirements, develop failure criteria, and predict the thick adhesive joint behavior by finite element modeling.
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Xiao Y, Mu X, Chen S, Jiang G, Xu Z, Ma C, Song L, Hu Y. Biomass-derived polyphosphazene toward simultaneously enhancing the flame retardancy and mechanical properties of epoxy resins. Chemosphere 2023; 311:137058. [PMID: 36419266 DOI: 10.1016/j.chemosphere.2022.137058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/23/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
As one of the most widely used polymers, the intrinsic brittleness and high flammability bring about a stringent requirement for the practical application of epoxy resins (EPs). It is difficult to toughen EP without compromising its mechanical and thermal properties for many conventional toughening agents. Here, a novel furan-derived bio-based polyphosphazene (PFMP) with a flexible backbone and rigid side groups was prepared by the nucleophilic substitution reaction between polydichlorophosphazene (PDCP) and furfuralcohol. The resultant PFMP was incorporated into EP to realize exceptional toughening, strengthening, and flame retardant function. By adding 15% of PFMP, the limit oxygen index value is from 25% (EP) to 33% (EP/PFMP-15) and reaches the UL-94 V-0 rating. According to the cone calorimeter results, EP/PFMP-15 exhibits exceedingly reduced peak heat release rate (pHRR) (50.2%) and total heat release (THR) (49.6%). The significantly increased fire performance index (FPI) and decreased fire growth rate index (FIGRA) of EP/PFMP-15 demonstrate an improvement in its flame retardancy. The catalytic carbonization effect (condensed phase) and radical quenching effect (gas phase) of PFMP account for the greatly improved flame retardancy. Moreover, the impact and tensile tests indicate that PFMP can ameliorate the mechanical performance of EP with a maximum increase of impact strength (111.8%) and elongation at break (35.2%) for EP/PFMP-5. With 15% PFMP added, the tensile strength of EP/PFMP-15 increases by 40.4%. This work demonstrates that PFMP is expected to overcome shortcomings (flammability, toughness, and strength) of EP and spread its applied fields.
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Affiliation(s)
- Yuling Xiao
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China
| | - Xiaowei Mu
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China
| | - Siqi Chen
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China
| | - Guangyong Jiang
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China
| | - Zhoumei Xu
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China
| | - Chao Ma
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China.
| | - Lei Song
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China.
| | - Yuan Hu
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, PR China
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Oshri A, Cui Z, Carvalho C, Liu S. Is perceived stress linked to enhanced cognitive functioning and reduced risk for psychopathology? Testing the hormesis hypothesis. Psychiatry Res 2022; 314:114644. [PMID: 35772214 DOI: 10.1016/j.psychres.2022.114644] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 03/09/2022] [Accepted: 05/17/2022] [Indexed: 12/25/2022]
Abstract
Extensive research documents the impact of psychosocial stress on risk for the development of psychiatric symptoms across one's lifespan. Further, evidence exists that cognitive functioning mediates this link. However, a growing body of research suggests that limited stress can result in cognitive benefits that may contribute to resilience. The hypothesis that low-to-moderate levels of stress are linked to more adaptive outcomes has been referred to as hormesis. Using a sample of young adults from the Human Connectome Project (N = 1,206, 54.4% female, Mage = 28.84), the present study aims to test the hormetic effect between low-to-moderate perceived stress and psychopathological symptoms (internalizing and externalizing symptoms), as well as to cross-sectionally explore the intermediate role of cognitive functioning in this effect. Results showed cognitive functioning as a potential intermediating mechanism underlying the curvilinear associations between perceived stress and externalizing, but not internalizing, behaviors. This study provides preliminary support for the benefits of limited stress to the process of human resilience.
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Liang X, Li X, Tang Y, Zhang X, Wei W, Liu X. Hyperbranched epoxy resin-grafted graphene oxide for efficient and all-purpose epoxy resin modification. J Colloid Interface Sci 2021; 611:105-117. [PMID: 34933189 DOI: 10.1016/j.jcis.2021.12.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 12/01/2021] [Accepted: 12/11/2021] [Indexed: 12/26/2022]
Abstract
Despite great efforts have been made on epoxy resins modification, development of additives that can be used to efficiently and universally modify epoxy composites remains a challenging task. Herein, graphene oxide (GO) sheets were covalently linked with hyperbranched epoxy resin (HBPEE-epoxy) to form HBPEE-epoxy functionalized GO (HPE-GO), which was then incorporated into epoxy resin (EP) matrix to achieve efficient and all-purpose enhancement of the properties of EPs. Compared with unmodified GO sheets, the functionalized HPE-GO sheets were better dispersed and exhibited better interfacial compatibility with the epoxy matrix, and consequently, the mechanical and thermal properties of HPE-GO/EP composites improved significantly compared to unmodified GO/EP composites. The tensile strength, flexural strength, impact strength, and fracture toughness (KIC) of EP composites containing 0.5 wt% HPE-GO increased by 65.0%, 36.2%, 259.1%, and 178.9%, respectively, compared with those for the neat EP. The storage modulus (E'), glass transition temperature (Tg), and thermal stability (T5%) also showed modest improvements. Furthermore, the HPE-GO/EP composites exhibited optimal thermal conductivities and thermal expansion properties, while maintaining higher volume resistivities compared with GO/EP composites. The results of this study support that HPE-GO is a promising, all-purpose modifier for EPs.
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Affiliation(s)
- Xue Liang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, No 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, PR China
| | - Xiaojie Li
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, No 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, PR China.
| | - Yong Tang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, No 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, PR China
| | - Xiyu Zhang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, No 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, PR China
| | - Wei Wei
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, No 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, PR China
| | - Xiaoya Liu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, No 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, PR China.
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Ding Y, Chen X, Huang D, Fan B, Pan L, Zhang K, Li Y. Post-chemical grafting poly(methyl methacrylate) to commercially renewable elastomer as effective modifiers for polylactide blends. Int J Biol Macromol 2021; 181:718-733. [PMID: 33811931 DOI: 10.1016/j.ijbiomac.2021.03.139] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 03/20/2021] [Accepted: 03/23/2021] [Indexed: 11/30/2022]
Abstract
A novel poly(epichlorohydrin-co-ethylene oxide)-g-poly(methyl methacrylate) copolymer (ECO-g-PMMA) was successfully synthesized from a commercially renewable elastomer via the ATRP method. The graft copolymer was investigated as a toughening agent and compatibilizer for polylactide (PLA) and PLA/ECO blends, respectively. Binary blending PLA with the copolymers (5-15 wt%) significantly improved the strain at break of PLA above 200% without a great strength loss. More importantly, the ternary PLA/ECO/ECO-g-PMMA copolymer blends exhibited a remarkably high impact strength of 96.9 kJ/m2 with non-broken behaviors. An interesting phase structure transformation from a typical sea-island structure to a unique quasi-continuous network structure was observed with varying the content of ECO-g-PMMA from 0 to 15 wt% in the ternary blends. The native toughening mechanism analysis indicated the synergistic toughening effect of the good interfacial adhesion and unique quasi-continuous morphology endowed the ternary blends with excellent mechanical performance.
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Affiliation(s)
- Yingli Ding
- School of Chemical Engineering and Technology, Tianjin University, Peiyang Park Campus: No.135 Yaguan Road, Haihe Education Park, Tianjin 300350, China
| | - Xiangjian Chen
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Peiyang Park Campus: No.135 Yaguan Road, Haihe Education Park, Tianjin 300350, China
| | - Dong Huang
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Peiyang Park Campus: No.135 Yaguan Road, Haihe Education Park, Tianjin 300350, China
| | - Baomin Fan
- Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing Technology and Business University, Beijing 100048, China
| | - Li Pan
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Peiyang Park Campus: No.135 Yaguan Road, Haihe Education Park, Tianjin 300350, China.
| | - Kunyu Zhang
- School of Chemical Engineering and Technology, Tianjin University, Peiyang Park Campus: No.135 Yaguan Road, Haihe Education Park, Tianjin 300350, China.
| | - Yuesheng Li
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Peiyang Park Campus: No.135 Yaguan Road, Haihe Education Park, Tianjin 300350, China
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Li Y, Zhang M, Weng Y, Wang L, Song J. Effects of microencapsulated abamectin on the mechanical, cross-linking, and release properties of PBS. Colloids Surf B Biointerfaces 2020; 196:111290. [PMID: 32829100 DOI: 10.1016/j.colsurfb.2020.111290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 06/24/2020] [Accepted: 07/27/2020] [Indexed: 11/20/2022]
Abstract
Herein, nanocomposite microencapsulated abamectin (A-G-G) have been prepared by composite coacervation method with gelatin and gum arabic as the wall materials and abamectin (A-W) as core material. The formation mechanism of A-G-G was determined by fourier-transform infrared spectroscopy, scanning electron microscopy, and other characterization methods. Then, polybutylene succinate (PBS)/A-G-G composite films with different contents of A-G-G microcapsules were prepared. The effects of adding A-G-G microcapsules on the mechanical and sustained-release properties of the composite films were studied. Results show that there is a strong interaction between the CO groups in PBS and free OH of the A-G-G microcapsules. With an increase in the A-G-G microcapsule content, the elongation at the break of composite films increases significantly. When the A-G-G content is 15 %, the elongation at break of the composite films reaches 178.6 ± 6.26 %. The maximum water absorption is 329 ± 5.84 %. Overall, the PBS/A-G-G composite films exhibit good slow-release performance.
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Mousavi A, Aliha MRM, Imani DM. Effects of biocompatible Nanofillers on mixed-mode I and II fracture toughness of PMMA base dentures. J Mech Behav Biomed Mater 2020; 103:103566. [PMID: 32090956 DOI: 10.1016/j.jmbbm.2019.103566] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/27/2019] [Accepted: 11/28/2019] [Indexed: 10/25/2022]
Abstract
A modified single edge cracked bend beam specimen called "inclined edge crack asymmetric bend" (IE-CAB) specimen was designed and proposed for investigating mixed mode I/II fracture toughness behavior of brittle materials. Using a large number of finite element analyses performed for different geometry and loading conditions, it was demonstrated that unlike the conventional single edge notch beam specimen, the IE-CAB configuration can provide full combinations of mode mixities from pure mode I to pure mode II. Then the IE-CAB specimen was employed for mixed mode I/II fracture toughness testing of two PMMA based denture materials (i.e. neat PMMA and toughened PMMA with Nano-hydroxyapatite (HAP)and Nano-alumina (Al2O3) particles). The obtained experimental results showed that adding bio-compatible (HAP and Al2O3) Nano-particles can increase both modes I and II fracture resistance (KIc and KIIc) values of base PMMA denture. However, the influence of such particles was more pronounced on enhancing mode I fracture toughness (KIc) value. Pure mode II fracture toughness value was obtained less than the pure mode I fracture toughness in the tested specimen showing the higher crack growth risk of such PMMA base dentures against dominantly shear loads. The well-known maximum tangential stress theory was also used for estimating the obtained experimental data both for mixed mode fracture toughness and fracture initiation direction in the tested PMMA base denture materials.
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Affiliation(s)
- A Mousavi
- Welding and Joining Research Center, School of Industrial Engineering, Iran University of Science and Technology (IUST), Narmak, 16486-13114, Tehran, Iran
| | - M R M Aliha
- Welding and Joining Research Center, School of Industrial Engineering, Iran University of Science and Technology (IUST), Narmak, 16486-13114, Tehran, Iran.
| | - D M Imani
- Welding and Joining Research Center, School of Industrial Engineering, Iran University of Science and Technology (IUST), Narmak, 16486-13114, Tehran, Iran
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11
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Liu Z, Zhang Z, Ritchie RO. Interfacial toughening effect of suture structures. Acta Biomater 2020; 102:75-82. [PMID: 31756553 DOI: 10.1016/j.actbio.2019.11.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/02/2019] [Accepted: 11/15/2019] [Indexed: 10/25/2022]
Abstract
Suture interfaces are one of the most common architectural designs in natural material-systems and are critical for ensuring multiple functionalities by providing flexibility while maintaining connectivity. Despite intensive studies on the mechanical role of suture structures, there is still a lack of understanding on the fracture mechanics of suture interfaces in terms of their interactions with impinging cracks. Here we reveal an interfacial toughening effect of suture structures by means of "excluding" cracks away from interfaces based on a dimensionless micro-mechanical model for single-leveled and hierarchical suture interfaces with triangular-shaped suture teeth. The effective stress-intensity driving forces for crack deflection along, versus penetration through, an interface at first impingement and on subsequent kinking are formulated and compared with the corresponding resistances. Quantitative criteria are established for discerning the cracking modes and fracture resistance of suture interfaces with their dependences on sutural tooth sharpness and interfacial toughness clarified. Additionally, the effects of structural hierarchy are elucidated through a consideration of hierarchical suture interfaces with fractal-like geometries. This study may offer guidance for designing bioinspired suture structures, especially for toughening materials where interfaces are a key weakness. STATEMENT OF SIGNIFICANCE: Suture interfaces are one of the most common architectural material designs in biological systems, and are found in a wide range of species including armadillo osteoderms, boxfish armor, pangolin scales and insect cuticles. They are designed to provide flexibility while maintaining connectivity. Despite many studies on the mechanical role of suture structures, there is still little understanding of their role in terms of interactions with impinging cracks. Here we reveal an interfacial toughening effect of suture structures by means of "excluding" cracks away from interfaces based on a dimensionless micro-mechanical model for single-leveled and hierarchical suture interfaces with triangular-shaped suture teeth. Quantitative criteria are established for discerning the cracking mode and fracture resistance of the interfaces with their dependences on sutural tooth sharpness and interfacial toughness clarified.
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12
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Sun J, Zhao J, Huang Z, Yan K, Shen X, Xing J, Gao Y, Jian Y, Yang H, Li B. A Review on Binderless Tungsten Carbide: Development and Application. Nanomicro Lett 2019; 12:13. [PMID: 34138087 PMCID: PMC7770855 DOI: 10.1007/s40820-019-0346-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 11/20/2019] [Indexed: 05/16/2023]
Abstract
WC-Co alloys have enjoyed great practical significance owing to their excellent properties during the past decades. Despite the advantages, however, recently there have been concerns about the challenges associated with the use of Co, i.e. price instability, toxicity and properties degeneration, which necessitates the fabrication of binderless tungsten carbide (BTC). On the other hand, BTC or BTC composites, none of them, to date has been commercialized and produced on an industrial scale, but only used to a limited extent for specialized applications, such as mechanical seals undergoing high burthen as well as high temperature electrical contacts. There are two challenges in developing BTC: fully densifying the sintered body together with achieving a high toughness. Thus, this review applies towards comprehensively summarize the current knowledge of sintering behavior, microstructure, and mechanical properties of BTC, highlighting the densification improving strategies as well as toughening methods, so as to provide reference for those who would like to enhance the performance of BTC with better reliability advancing them to further wide applications and prepare the material in a way that is environment friendly, harmless to human health and low in production cost. This paper shows that the fabrication of highly dense and high-performance BTC is economically and technically feasible. The properties of BTC can be tailored by judiciously selecting the chemical composition coupled with taking into careful account the effects of processing techniques and parameters.
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Affiliation(s)
- Jialin Sun
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
| | - Jun Zhao
- Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE, School of Mechanical Engineering, Shandong University, Jinan, 250061, People's Republic of China
| | - Zhifu Huang
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
| | - Ke Yan
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
| | - Xuehui Shen
- School of Mechanical and Automotive Engineering, Qilu University of Technology, Jinan, 250353, People's Republic of China
| | - Jiandong Xing
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Yimin Gao
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Yongxin Jian
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Hejie Yang
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Bo Li
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
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Koh JJ, Zhang X, He C. Fully biodegradable Poly(lactic acid)/Starch blends: A review of toughening strategies. Int J Biol Macromol 2017; 109:99-113. [PMID: 29248552 DOI: 10.1016/j.ijbiomac.2017.12.048] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 11/27/2017] [Accepted: 12/07/2017] [Indexed: 01/24/2023]
Abstract
Polylactic acid (PLA) and Starch are both bio-based biodegradable polymers that have properties that are complementary to each other. PLA/starch blend exploits the good mechanical property of PLA and the low cost of Starch. However, PLA/Starch blend is intrinsically brittle. This paper reviews the current state of arts in toughening of PLA/Starch blend, which are categorized as: Additive Plasticization, Mixture Softening, Elastomer Toughening and Interphase Compatibilization. These strategies are not mutually exclusive and can be applied jointly in a single blend, opening up a wide range of toughening techniques that can be employed in PLA/Starch blend. Even though significant progress has been made in this area, there is still much room for research, in order to achieve easy to process, fully bio-based and completely biodegradable PLA/Starch blends that have mechanical properties suitable for a wide range of applications.
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Affiliation(s)
- J Justin Koh
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, 117576, Singapore; Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A*STAR), 73 Nanyang Drive, 637662, Singapore
| | - Xiwen Zhang
- Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A*STAR), 73 Nanyang Drive, 637662, Singapore
| | - Chaobin He
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, 117576, Singapore; Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, 138634, Singapore.
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14
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Zubrowska A, Piorkowska E, Kowalewska A, Cichorek M. Novel blends of polylactide with ethylene glycol derivatives of POSS. Colloid Polym Sci 2014; 293:23-33. [PMID: 25598571 PMCID: PMC4287653 DOI: 10.1007/s00396-014-3344-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 06/12/2014] [Accepted: 07/15/2014] [Indexed: 10/24/2022]
Abstract
Polylactide (PLA), a main biodegradable and biobased candidate for the replacement of petrochemical polymers, is stiff and brittle at room conditions. It is therefore of high interest to formulate new PLA-based materials suitable for applications demanding flexibility and toughness. In this work, novel blends of PLA with polyhedral oligomeric silsesquioxanes (POSS) grafted with longer (P1) and shorter (P2) arms of ethylene glycol derivatives were prepared and studied. It was hypothesized that, owing to their architecture with the central POSS cage grafted with arms, miscibility and stability of the blends could be improved. Indeed, PLA/P1 blends were homogeneous despite P1 relatively high Mw of 9,500 g mol-1. The blend with 20 wt% of P1, having Tg at 16 °C, was transparent and flexible, elastomer-like material with excellent drawability. The blend remained homogeneous and retained its good drawability as well as flexibility during 6 months of aging at room temperature: a 2 % secant modulus of elasticity well below 100 MPa, a low yield stress below 2 MPa, and and a large strain at break of 8 (800 %). Contary to that, PLA/P2 blends were only partially miscible. Nevertheless, owing to the liquid state of the dispersed phase, the blend with 15 wt% of P2 was transparent and ductile, with Tg at 49 °C, a relatively high yield strength of 29 MPa, and a large strain at break of 2.3 (230 %). The toughening mechanism involved the initiation of crazes and facilitation of their propagation by the liquid inclusions via the local plasticization effect.
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Affiliation(s)
- Anna Zubrowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Ewa Piorkowska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Anna Kowalewska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
| | - Michal Cichorek
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland
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