IRANIAN POLYMER JOURNAL
·
2024
·Vol. 33
·期 5
·607-618
·
IF 2.4
Wang Guoqiang,Wu Yifan
Polylactic acid (PLA) is a biodegradable plastic with good tensile strength and can be produced from biomass. But there are some defects, such as poor ductility, low barrier properties and poor-UV resistance, which may limit the application and development of PLA. To increase the ductility of PLA, bio-based poly(butylene succinate-butylene furandicarboxylate) (PBSF) was combined with PLA to obtain the blends with different PBSF contents. The blend’s compatibility, crystallinity, thermal, mechanical and rheological properties were determined. The addition of PBSF inhibited the cold crystallization of PLA. Wide-angle X-ray diffractometry (WAXD) showed that the tensile sample of PBSF was semi-crystalline, and the tensile samples of PLA and the blends were almost amorphous. A substantial shift in the stretching vibration of C=O was observed in the FTIR spectra, indicating that the oxygen atom in the furan ring improves the intermolecular interaction between PLA and PBSF. The fracture surfaces of the blends varied from typical brittle morphology to ductile morphology as a result of the addition of PBSF. At 180 °C, the complex viscosity decreased as the PBSF concentration increased. Tensile strength was 31.5 MPa and elongation-at-break was 390% when the amount of PBSF in the blend reached 30% (by weight). The findings demonstrate that PBSF can improve the ductility and processability of PLA. Graphical Abstract
研究领域:
材料科学
·
生物质工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Yijian Wu,Hui Zhang,Baoqing Shentu,Zhixue Weng
Organo-montmorillonite (OMMT) was introduced into SEBS-g-MA toughened poly(phenylene oxide)/polyamide-6 (PPO/PA6) blends simply by melt extrusion. The effects of OMMT on morphology, rheology, and mechanical behaviors of toughened PPO/PA6 nanocomposites were studied by scanning electron microscope, transmission electron microscope, capillary rheometer and mechanical tests. The addition of OMMT could decrease the size of dispersed PPO domains in PA6 matrix and melt viscosity of the toughened PPO/PA6 nanocomposites. Besides, exfoliated OMMT also brought significant improvement of tensile properties and heat deflection temperature (HDT), simultaneously. For nanocomposites with exfoliated OMMT, OMMT induced more core–shell toughening particles with the optimized size, and thus, elastomer-OMMT synergistic toughening was achieved in the PPO/PA6 nanocomposites. Consequently, PPO/PA6 nanocomposites with high tensile strength, excellent impact performance, improved HDT, and good processability were obtained.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Polymers
·
2019
·Vol. 11
·期 9
·1522
·
IF 3.164
Ming Zhang,Mingqing Chen,Zhongbin Ni
We synthesized PPG-terminated tetra-carbamates as a new toughening additive for epoxy thermosets through facile addition reaction of hexamethylene diisocyanate (HDI) with poly(tetra-methylene glycols) (PTMG) and poly(propylene glycols) (PPG). The effects of prepared tetra-carbamates on the rheological behavior of neat epoxy resin were studied along with the various cured properties of their modified epoxy systems. Four carbamate groups (–NHCOO–) endow the prepared additives not only with good intramolecular interactions, but also with optimal intermolecular interactions with epoxy polymers. This results in the suitable miscibility of the additives with the epoxy matrix for the formation of the typical biphasic structure of microparticles dispersed in the epoxy matrix via polymerization-induced microphase separation. The impact strength and critical stress concentration factor (KIC) of cured modified epoxy systems with the additives are significantly higher than those of unmodified epoxy systems, without sacrificing the processability (Tg) and flexural strength. The toughening mechanism is understood as a synergism combination among the phase separation mechanism, the in situ homogeneous toughening mechanism, and the particle cavitation mechanism.Keywords:tetra-carbamates;epoxy polymer;toughening;microphase separation;particle
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2020
·
IF 0
Rong Yang,Hongwei Cao,Pengliang Zhang,Li Chen,Guoxiang Zou,Xin Zhang,Jinchun Li
Poly(lactic acid) (PLA) is a well-known sustainable plastic but with an inherent brittleness, slow crystallization rate, and poor heat resistance, which significantly limits its application. In this work, toughened PLA with a balanced tensile strength, fast crystallization rate, and great heat resistance was obtained by dynamic vulcanization with an unsaturated liquid crystalline polyester (PBDPSM) in the presence of a free radical initiator of dicumyl peroxide (DCP). PBDPSM is efficient in enhancing the tensile toughness of PLA in that the elongation at break of PLA significantly increased from 15 to 179% while adding only 1 wt % PBDPSM. When adding 8 wt % PBDPSM, the PLA/PBDPSM8 blend has an elongation at break of 265%, tensile toughness of 107.2 MJ/m3, and notched Izod impact strength of 22.5 kJ/m2. Moreover, it keeps a high tensile strength of 62.6 MPa. In addition, the crystallization rate of PLA has dramatically accelerated due to the apparent nucleation effect induced by DCP and PBDPSM. PLA/PBDPSM3 shows the highest crystallinity with 44.4%. Furthermore, it shows a high Vicat softening temperature of 152.2 °C, which is 92.2 °C higher than that of neat PLA. Finally, highly toughened PLA materials with balanced tensile strength and good heat-resistant properties were realized.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
Journal of Industrial Textiles
·
2018
·
IF 1.283
Feichao Zhu,Juanjuan Su,Mingjun Wang,Munir Hussain,Bin Yu,Jian Han
With increasing demands on the high-performance and environmental-friendly melt-blown nonwovens (MBs) for separation and filtration, herein, we reported a poly(lactic acid)/polyamide 11 (PLA/PA11) 100% bio-based MBs in situ compatibilized by dual-monomer glycidyl methacrylate–styrene melt-grafted poly(lactic acid) (PLA-g-(St-co-GMA)). The morphology, crystallization, thermal and rheological behaviors of reactive extruded PLA/PA11/PLA-g-(St-co-GMA) melt blends were investigated, and the structure and filtration performance of corresponding MBs were fully characterized. The results indicated that the interface between PLA and PA11 were effectively improved due to the compatibilizer of PLA-g-(St-co-GMA). PA11 promoted the cold crystallization and enhanced the thermal stability of PLA matrix. The reactive blends displayed a higher viscosity with unchanged rheological behaviors compared with PLA. In comparison with PLA MBs, the average fiber diameter and pore size of PLA/PA11/PLA-g-(St-co-GMA) MBs were slightly increased, whereas the strength and toughness were significantly improved. All the PLA/PA11/PLA-g-(St-co-GMA) MBs presented high air permeability and low filtration resistance. High filtration efficiency (>99.8%) could also be obtained especially for the target particles with diameters larger than 2.5 µm.
研究领域:
材料科学
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环境科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Coatings
·
2023
·Vol. 13
·期 2
·475
·
IF 3.4
Shuai Guo,Fusheng Zhu,Zhimeng Xiu,Mu Zhang,Xudong Sun
In this study, a type of micro-nano Si3N4matrix ceramic cutting tool material was successfully prepared by controlling the addition amount of TiC0.7N0.3and the hot-pressing sintering temperature. The effects of different volume fractions of TiC0.7N0.3on the microstructure, mechanical properties, particle size distribution, and relative density of Si3N4ceramic tools at the same temperature were investigated. The results show that the addition of TiC0.7N0.3makes the β-Si3N4grains with different diameters and aspect ratios interlaced and tightly bonded, thus achieving the strengthening and toughening effects. In addition, the effects of different hot-press sintering temperatures on the properties of Si3N4ceramic tool materials were studied. It was concluded that the density of the material increased with the increase of the hot-pressing temperature. The relative density, flexural strength, and fracture toughness of the samples with 1 vol% TiC0.7N0.3added at 1750 °C and 30 MPa pressure reached 99.22%, 993 MPa, and 9.81 MPa·m1/2, respectively.Keywords:Si3N4;ceramic cutting tool;hot-pressing sintering;TiC0.7N0.3;self-toughening
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2022
·Vol. 9
·期 6
·065307
·
IF 2.025
Wenpeng Chu,Song Yan,Ziqing Cai,Shiwen Yang,Xinghui Hu,Xianze Yin
The inherent brittleness of poly(lactic acid) (PLA) usually limits its application in the high ductile requirements sector. To address the above issue, n-ethyl-p-toluenesulfonamide (N-PTSA) as the toughening agent, was utilized to optimize the rheological and mechanical performance of the PLA matrix. The microstructure, thermal stability, rheological behavior, and mechanical properties of PLA/N-PTSA were systematically investigated. A rheological test showed that N-PTSA can reduce the melt processing viscosity of PLA matrix and the decreasing of processing viscosity strongly depended on the N-PTSA content rather than shear rate. Mechanical properties results confirmed that the 14.7% N-PTSA can improve the toughness of PLA/N-PTSA without deteriorating the tensile strength and Yong's modulus. This reason was ascribed to the reduction of hydrogen bonds of PLA matrix caused by N-PTSA to accelerate the movement of PLA molecular chain meanwhile forming new hydrogen bond between PLA and N-PTSA. By adding N-PTSA, the thermal stability of PLA was decreased. With the synergistic effect of plasticizing and toughening N-PTSA, the rheology and mechanical properties of PLA had been effectively improved.
研究领域:
材料科学
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高分子化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhaoyan Zhang,Shaoping Qian,Xinyu Li,Changfa Zhu,Zhijie Li
Polylactic acid (PLA) is one of the most promising biodegradable materials, but poor toughness severely limits its application. Ionic liquids (ILs) have excellent plasticizing effects on PLA, but strength reduction and plasticizer precipitation remain worrisome. Herein, nanofibrillated cellulose (NFC), with excellent morphology, high modulus and strength, was prepared to reinforce PLA plasticization systems. Moreover, its numerous surface hydroxyl groups were tailored to bond with ILs, reducing plasticizer precipitation. The different sulfonation degrees of NFCs (low LSNFC, medium MSNFC, high HSNFC) and the influence of NFC amounts (0–7 wt%) on the mechanical, thermal and plasticizer precipitation properties of PLA composites were investigated. The results indicate that network-like C2/C3-sulfonated NFCs were successfully prepared through simple processing steps. Noteworthy, the tensile elongations of PLA composites increased with the addition of IL-XSNFC (all three degrees), with no significant reduction in tensile strength and modulus. The addition of 7 wt% IL-HSNFC resulted in an elongation of 25.01 % for PLA composites, which is 3.6 times that of pure PLA. Adding 3 wt% IL-MSNFC achieved ultra-high impact toughness of 3.19 kJ/m 2 , nearly double that of pure PLA. Interestingly, with increasing sulfonation degree, the amount of ILs precipitation in PLA composites significantly decreased. The precipitation rate of the PLA composite with IL-HSNFC is only 24 % of the counterparts with IL-NFC. This work presents an innovative method to improve interface compatibility, providing a new strategy to reduce plasticizer precipitation and broaden the application scope of PLA.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
Yu Zhang,Gang Wang,Yuxuan Xu,Jiajun Sun,Xiaohong Zhang,Ting Zheng,Lili Zhang
The high brittleness of epoxy resin at cryogenic temperature restricts their wide application in cryogenic engineering. In this study, polyhedral oligomeric silsesquioxane (POSS) with -Si-O-Si- molecular chains were synthesized, and the mechanical properties of diglycidyl ether of bisphenol A (E51 epoxy resin) were significantly enhanced at room temperature (RT) by incorporating a 4% POSS and curing agent 4,4′-diamino-diphenylmethane (DDM) as the E51/POSS/DDM resin system. Subsequently, by adding different contents of epoxidation hydroxyl-terminated polybutadiene (EHTPB) into the E51/POSS/DDM resin system, the EHTPB-E51/POSS/DDM resin system was prepared. The investigation into the impact of EHTPB content on the mechanical properties of EHTPB-E51/POSS/DDM resin system at room temperature (RT) revealed that EHTPB-E51/POSS/DDM resin system with 10% EHTPB exhibited the most favorable results. Specifically, the elongation at break, flexural strength , and critical stress intensity factor (K IC ) were measured to be 6.82%, 143.75 MPa, and 1.83 MPa m 1/2 , respectively. These values demonstrated a notable improvement of 53.3%, 26.9%, and 86.7% compared to those for the E51/DDM resin system. Concurrently, at 77 K, the elongation at break and critical stress intensity factor (K IC ) increased by 37.8% and 73.5%, respectively. The toughening mechanism of the prepared EHTPB-E51/POSS/DDM resin system was further explored through resin-curing cross-linking simulation networks and SEM images of the fracture surface of resin samples. The study of EHTPB and POSS synergistically toughened epoxy resin provided a new efficient method to prepare epoxy resins with high toughness at low temperatures.
研究领域:
材料科学
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工程学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Lechen Yang,Yong Li,Dajun Huan,Hewen Zhang,Chunling Zhu
Epoxy resin (EP) is usually brittle because of highly cross-linked chemical structure , so it is necessary to carry out research on toughening of epoxy resin. Here, a modified epoxy resin with enhanced mechanical toughness and strength was prepared using a novel modifier (PEA-BA), synthesized from polyetheramine D-400 (PEA) and benzoic acid (BA). Polyether chains that represent flexible structures, and aromatic rings representing rigid structures, were integrated together into the modifier to achieve simultaneous enhancement of the toughness and strength of the resulting epoxy resin. Moreover, the aromatic rings in PEA-BA formed π-π interactions with the aromatic rings in the EP network, further increasing the ductility of the modified epoxy resin. Research results demonstrated that the modified epoxy resin exhibited significantly improved elongation at break (increasing from 6.7 % to 39.2 %), as well as higher tensile strength (from 61.9 MPa to 69.3 MPa) and impact strength (from 25.3 kJ·m −2 to 62.9 kJ·m −2 ). Importantly, the glass transition temperature and thermal stability of the modified epoxy resin were not markedly reduced. The above properties indicated that PEA-BA achieved a favorable combination of high strength and ductility of epoxy resin, providing a new idea for toughening epoxy resin.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Reaction Chemistry & Engineering
·
2025
·
IF 3.1
Jiawei Liu,Tongjia Zhang,Shoutian Qiu,Lixin Song,Guangyuan Zhou,Honghua Wang
The introduction of reactive groups capable of participating in epoxy cross-linking into the molecular chains of conventional thermoplastic toughening agents effectively enhances the interfacial compatibility between thermoplastic and thermosetting resins, resulting in a significant improvement in system impact toughness. Building on this approach, this study innovatively incorporates polar nitrile groups into the molecular chains of thermoplastic polyaryletherketone agents containing terminal reactive groups, thereby exploring the synergistic mechanism between reactive and nitrile groups. A systematic investigation is conducted to examine how variations in the nitrile group content and the addition level of the toughening agent influence the toughening effect of epoxy resin. Additionally, the influence of different epoxy system phase structures on mechanical properties is assessed. Experimental results reveal that when the toughening agent PEKCN-OH is added at less than 10 parts per hundred resin (phr), the epoxy system exhibits a sea-island morphology, with the impact strength decreasing with increasing nitrile group content. When no nitrile groups are present (using PEKC-OH resin), the impact strength reaches 23.5 kJ m−2, representing a 97% increase compared to the control without the toughening agent. For addition levels exceeding 10 phr, the system transitions to a bicontinuous structure. In this regime, the impact strength initially increases before decreasing as the nitrile group content increases. At a nitrile group content of 50% (using PEKCN-OH-2 resin), the impact strength reaches 25.8 kJ m−2, representing a 117% increase. Importantly, the addition of these toughening agents not only prevents a reduction in the service temperature of the epoxy resin but also enhances its thermal stability. In conclusion, the PEKCN-OH developed in this study serves as a highly efficient, easily prepared reactive thermoplastic toughening agent suitable for industrial production. It holds great promise for use in demanding industrial applications, including aerospace, electronics and electrical appliances, and automotive manufacturing. The findings are expected to make significant contributions to material innovation and product performance optimization in these sectors.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2025
·
IF 3.2
Yini Cui,Jiyong Zhao,Minjie Qu,Zhipeng Wang
The toughened polyphenylene sulfide (PPS) was prepared using copolymer poly(aryl ether sulfone ketone) as the toughening agent, which was synthesized through copolycondensation of 2-phenyl-3,3-bis(4-hydroxyphenyl)phthalimide, 1,4-bis(4-fluorophenyl)butane-1,4-diketone (BFB), and bis(4-fluorophenyl)sulfone (DFS) as monomers. The properties of the copolymers were regulated by controlling the ratio of BFB and DFS. The glass transition temperature ( T g ) exceeds 210°C, and the thermal decomposition temperature ( T d 5% ) surpasses 430°C, demonstrating the copolymer's excellent thermal stability. When the mole ratio of sulfone to ketone was 8:2, the impact strength exhibited an increase of approximately 178% compared to that of neat PPS. The influences of the toughening agent and blending method on the thermal properties, rheological properties, and mechanical properties of the blends were examined. Highlights Copolymer was synthesized as a toughening agent for polyphenylene sulfide (PPS). Copolymer demonstrates good thermal stability properties. Adding copolymer and EGMA significantly improved the toughness of PPS.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子