POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Qingkun Liu,Peng Wei,Chuanbo Cong,Xiaoyu Meng,Qiong Zhou
A novel antioxidant denoted as HVA-2@MB was synthesized through the reaction of N,N'-1,3-phenylene bismaleimide (HVA-2) and 2-mercaptobenzimidazole (MB) catalyzed by triethylamine. This antioxidant had high molecular weight as well as crosslinking and antioxidation functions. Then, the effect of HVA-2@MB on the crosslinking and antioxidation behaviors of ethylene-propylene-diene rubber (EPDM) was investigated. HVA-2@MB greatly reduced the inhibitory effect of antioxidants on rubber vulcanization and improved the crosslinking density of rubber. In addition, due to the reactivity of HVA-2@MB, the antioxidant groups were chemically bonded to the rubber network, which significantly reduced the migration of antioxidants in the thermo-oxidative environment, thereby improving the thermo-oxidative stability of the rubber. Therefore, compared with MB/EPDM composites, HVA-2@MB/EPDM composites exhibited better mechanical properties and thermo-oxidative stability during thermo-oxidative aging.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELASTOMERS AND PLASTICS
·
2017
·
IF 0.787
Quan Zhou,Lu Yan,Xuejun Lai,Hongqiang Li,Xingrong Zeng
A new kind of polypropylene/ethylene–propylene–diene monomer (PP/EPDM) thermoplastic elastomer (TPE) with good mechanical properties and flame retardancy was prepared via in situ peroxide-induced dynamic vulcanization using lanthanum trimethacrylate (LaTMA) as a reinforcing agent. The morphology, structure, and mechanical properties and reinforcement mechanism of PP/EPDM/LaTMA TPE were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, rubber process analyzer, cross-link density test, and so on. The flame retardancy was investigated by limiting oxygen index (LOI) test. The results showed that when the amount of lanthanum oxide was 4.96 phr and methyl methacrylate was 7.85 phr, the compatibility between EPDM and PP was greatly improved. Besides, the tensile strength, tear strength, elongation at break, and hardness (shore A) of PP/EPDM/LaTMA TPE were increased from 6.2 MPa, 41.7 kN m−1, 148%, and 81 up to 11.1 MPa, 77.3 kN m−1, 365%, and 89, respectively. And the LOI of PP/EPDM/LaTMA TPE was increased to 19.0%. The SEM images, the higher G′, and the ionic cross-link suggested that a strong filler–filler network was formed by the polymerization and the grafted of LaTMA in the PP and EPDM phase which enhanced the compatibility between PP and EPDM. The DSC and FTIR results further proved that during the processing.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2024
·Vol. 31
·期 8
·1-13
·
IF 2.6
Wang Y. B.,Deng X. L.,Cao B. Y.,Feng H. P.,Chen J.,Li P. D.,Ren L.,Zhang M. Y.
In this article, a strategy is proposed to prepare highly toughened composites from polypropylene (PP), rice husk charcoal (RHC) and glycidyl methacrylate (GMA)-modified EPDM using melt blending and hot pressing. The structure of GMA-modified EPDM is confirmed by Fourier transform infrared spectroscopy (FTIR). The influences of the amounts of EPDM and GMA-modified EPDM on PP composites are investigated by virtue of mechanical properties testing, dimensional stability analysis, thermogravimetric analysis (TGA), X ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that the incorporation of GMA-modified EPDM significantly improves the toughness of PP composites and compared to PRHC the impact strength of PRKEG10 is up to the value of 537 J/m and increases by 555%, concurrently the tensile strength and modulus exhibit less decrease with the value of 8.22 MPa and 353 MPa, respectively. Shrinkage measurements show the dimensional change rates of length, width, and height decrease from 3.2%, 2.9%, and 3.3% to 1.73%, 1.46%, and 1.93%, respectively, improving the dimensional stability of PP composites. SEM reveals that shear yield and cavitation during the loading process lead to the excellent toughness of PP composites. This strategy provides a novel route to fabricate high ductility rice husk charcoal-based PP composites and expand certain industrial application.
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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 5
·49767
·
IF 2.52
Chengtian Xiong,Xiaoqing Li,Hezhi He,Bin Xue,Yi Wang,Jiqian Li,Zhiwen Zhu
Due to the disadvantages of lower tensile strength and fracture toughness, the widely application of Ethylene-propylene-diene-monomer rubber (EPDM) has been limited. In this study, a thermally reversible healing EPDM based elastomer with H-bonding and Zn-based-bonding dynamic cross-link network was prepared. The influence of mole ratio of ATA/MAH on tensile strength and fracture energy of mEPDM 0 -xATA was investigated. The results showed that increasing the content of ATA brings about a gradual improvement in tensile strength of the mEPDM 0 -xATA. Especially when the mole ratio of ATA/MAH is 1, the fracture energy of mEPDM 0 -ATA is dramatically enhanced to 33.9 MJ/m 3 , which is best among the ratios studied in our research. After curing, the effect of ZnCl 2 content on tensile strength and fracture energy of mEPDM-ATA-nZn was also studied. Meanwhile, the uniaxial cyclic loading-unloading tensile test was used to study the viscous damping properties of mEPDM-ATA-0.4Zn, which showed reversible repair properties after heat treatment. The results of dynamic rheological measurement showed that the damping properties were improved.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 14
·13321-13329
·
IF 2.195
Chi Qingguo,Yang Meng,Zhang Tiandong,Zhang Changhai
Ethylene propylene diene monomer (EPDM) is widely used as the reinforced insulation material for high voltage direct current (HVDC) cable accessories due to its excellent insulation properties, but its field-dependent conductivity is weak. In this paper, the silver particles (Ag) was prepared and filled into EPDM. The nonlinear conductivity characteristics and breakdown characteristics of the Ag/EPDM composites have been investigated. As the filled Ag content increases, the nonlinear conductivity becomes more obvious, with the maximum nonlinear coefficient reaching 2.45, however, the breakdown field strength is degraded seriously, when the Ag content of the composites reaches 0.5 wt%, the characteristic breakdown strength of the Ag/EPDM composites is reduced to 70.5 kV/mm (neat EPDM is 137.1/kV/mm). In order to relieve the severe degradation of breakdown field strength of Ag/EPDM composites, hexagonal boron nitride (BN), with perfect insulation and thermal properties, is introduced into Ag/EPDM composites. The results show that when 10 wt% of BN and 0.5 wt% of Ag are co-doped into EPDM, the characteristic breakdown field strength is 109.7 kV/mm, which increases by 55.6% compared to that of 0.5 wt% Ag/EPDM (70.5 kV/mm). In addition, the mechanical properties of BN/EPDM composites and Ag/BN/EPDM are improved significantly compared with neat EPDM.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2021
·Vol. 306
·期 5
·2000813
·
IF 4.367
Canchen Sun,Yuanyuan Wang,Bin Wang,Yanxia Cao,Jianfeng Wang,Yanyu Yang,Wanjie Wang
Here, zinc-neutralized ethylene propylene diene monomer (EPDM) ionomers with different neutralization levels are prepared through melt blending, and are then incorporated with polyamide 1012 (PA1012) to fabricate PA1012/EPDM ionomer blends. Interestingly, complex crosslinking networks are formed in the blends due to the construction of sacrificial bonds (Zn 2+ -carboxyl, Zn 2+ -amide). The as-formed network structure and sacrificial bond endow the PA/EPDM blends with largely enhanced toughness (16 times higher than that of neat PA), as well as balanced strength and stiffness. Meanwhile, the rheological behaviors of PA1012/EPDM ionomer blends indicate their relative low melting viscosity, which can avoid the processing shortcomings of plastics toughened with rubber. Moreover, PA1012/EPDM ionomer blends show obvious gelation behavior, and a maximum notched Izod impact strength exhibited at the gel point, in which unique double network structure can be observed obviously, indicating that there is a corresponding correlation between the rheological and mechanical parameters. Furthermore, the supper-toughening mechanism of PA1012/EPDM ionomer blends at gel point is explored, which origins from the large deformation and cavitation of rubber particles and the destruction of special double network morphologies. This study provides a novel and effective strategy to fabricate PA materials with outstanding toughness and excellent strength simultaneously.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
POLYMER
·
2020
·
IF 4.231
Ze Ding,Wenbin Yang,Fangfang He,Zhuoni Jiang,Ren He,Jinghui Fan,Kai Zhang
A novel elastic shape-stabilized phase change materials (SSPCMs) were obtained by reducing and vulcanizing a graphene oxide (GO) modified phase change latex (PCL), which is composed of ethylene propylene diene monomer (EPDM) and paraffin. GO as Pickering emulsifier assisted in fabricating EPDM/paraffin PCL. The zeta potential showed that the PCL was stable. Meanwhile, optical microscope and particle size test indicated that the average particle size was 3–5 μm. Scanning electron microscopy (SEM) showed that the SSPCMs were composed of reduced GO (RGO)-coated phase change composite microspheres (PCCMs). The intact RGO coating was beneficial to prevent the leakage of paraffin. According to the leakage rate test, the leakage rate of SSPCMs were decreased. When the GO content was 0.5%, the leakage rate of SSPCMs was 0.3%. The mechanical properties test showed that the tensile strength and elongation at break were up to 2.26 MPa and 1663.53%, respectively. The comprehensive properties of the prepared SSPCM make it have great potential in the field of building temperature control.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 24
·52346
·
IF 3.057
Yuhan Xu,Chenyu Zhao,Zhiyuan Guo,Wenjie Dong,Xiucai Liu,Weihong Guo
Polyamide is an engineering plastic, which has been widely used in industry and life. Polyamide 56, as a green and environmentally friendly bio-based product, is gradually replacing traditional petroleum-based products. However, in terms of auto parts, communication equipment, and mechanical products, a single polyamide monomer is difficult to meet the end-use standard. EPDM-g-MAH (ethylene propylene diene monomer grafted with maleic anhydride) is melt blended with bio-based polyamide 56 (PA56) in a twin-screw extruder to obtain polyamide elastomers with different formulations. Subsequently, its morphology and structure, thermodynamic properties, crystallinity, and mechanical properties were analyzed. The test results show that the composites containing 10% EPDM-g-MAH have better impact resistance and thermal properties in the range of adding 0‑20 wt% EPDM-g-MAH. In the fracture morphology analysis, it is found that the interface between the rubber phase and the polyamide phase fused well, and the elastomer showed the ductile fracture.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Yuqi Wang,Wei Zhao,Mingpu Li,Qing Zhuo,Yuanyuan Li,Linli Tan,Yingru Li,Hangyu Dong,Qiong Long
Utilizing foam-structured composite materials for electromagnetic shielding offers several advantages, including lightweight properties, low filler load, and a high absorption coefficient. However, their application in electromagnetic shielding is often limited by relatively lower mechanical performance. This study employed melt blending and chemical foaming processes to fabricate a lightweight EPDM/POE/KB composite foam with favorable mechanical characteristics, heat resistance, and electromagnetic absorbing performance. Significantly, the foam, with a density of 0.195 g/cm³, demonstrates an absorption-dominated shielding mechanism (absorption coefficient of 0.71) and good electromagnetic shielding performance of 20.57 dB in the X-band. The honeycomb structure formed within the material contributes to the multiple reflections of electromagnetic waves. Additionally, the composite foam exhibits excellent flexibility, with a fracture elongation greater than 150 %, alongside tensile and compressive strengths of 1.46 MPa and 0.92 MPa, respectively, demonstrating satisfactory mechanical performance. Furthermore, the composite foam also possesses good thermal stability. The study provides a low-cost and effective method for preparing lightweight, high-absorption coefficient, and excellent mechanical performance electromagnetic shielding foam.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Mingchao Wang,Yuan Wang,Xin Chen,Li Liu,Yetao Zhang,Chen Liu
Compared to the traditional open mixing process used for the production of the rubber composites, wet mixing process is a lower shear force mixing method. This article revealed the influence of the open mixing process and the wet mixing process on the microstructure, density, mechanical properties, and ablation performance of ethylene propylene diene monomer (EPDM) rubber/fiber/hollow glass microsphere composite system. The results showed that the wet mixing process increased the fiber length by more than 300% compared to the open mixing process, while the fragmentation rate of the hollow glass beads was reduced by 94.4%, these effectively maintained the structural integrity of the fibers and the hollow glass microsphere filler. By using the wet mixing process, the density of EPDM composite materials can be reduced by about 20%, and the tensile strength and ablation resistance of these composites were also significantly improved. Compared to polyimide fiber and aramid fiber short fibers, the wet mixing process of solution-based rubber had a more significant effect on improving the length and ablation resistance of phenolic fiber and carbon fiber fibers which having poor shear strength.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2021
·Vol. 306
·期 8
·2100184
·
IF 4.367
Chengjie Li,Zun Yuan,Lin Ye
In view of the facile reaction between carboxyl groups and zinc oxide (ZnO), Zn 2+ -carboxyl salt-bonding is constructed in ethylene propylene diene monomer (EPDM) rubber system by grafting reaction of glutamic acid (Glu), serving as sacrificial unit endowed EPDM-g-Glu/ZnO sample with excellent reprocessing and recycling ability. Through reaction of ZnO/methacrylic acid (MAA), EPDM-g-Glu/zinc dimethacrylate (ZDMA) composite is further prepared by in situ formation of ZDMA, and ZDMA is rapidly polymerized to form poly-ZDMA (PZDMA) containing massive Zn 2+ -carboxyl ion pairs once vulcanized, which exhibits fuzzy interface with the matrix. Relative to EPDM/ZDMA, the higher polymerization degree of ZDMA is achieved with the reduction of the size of PZDMA clusters, demonstrating the improvement of interfacial bonding, which results in the formation of a developed crosslinking network structure for EPDM-g-Glu/ZDMA. The mechanical strength, fracture toughness, and hysteresis loss of EPDM-g-Glu/ZDMA-40% show a significant increase in comparison with EPDM/CB-40% and EPDM/ZDMA-40%, meanwhile the relatively lower compression set and slower contact stress relaxation are achieved by energy dissipation mechanism of preferential rupture of Zn 2+ -carboxyl salt-bonding before breakage of covalent bonds during compression aging process, revealing the effective enhancement of durable sealing resilience performance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2019
·
IF 6.282
Rui Cui,Jianping Ding,Yukun Chen
The effect of magnesium acrylate (MgMA) on the interfacial compatibility and shape memory behavior of ethylene propylene diene monomer (EPDM)/polypropylene (PP) thermoplastic vulcanizates (TPVs) prepared through peroxide-induced dynamic vulcanization was investigated in this paper. MgMA could react with both PP and EPDM at their phase interface , which improved the EPDM/PP interfacial compatibilization . The PP continuous phase fixed the temporary shape and the crosslinked EPDM particles provided driving force for shape recovery. The improved phase interface played a significant role in the stress transmission between PP and EPDM phases. It is found that the shape fixity ratio (R f ) and the shape recovery ratio (R r ) of TPVs exceeded ∼90% and ∼92.5%, respectively. With the increase of MgMA content, the R f of TPVs increased firstly and then decreased, while the R r and recovery rate enhanced in the whole process. Furthermore, the mechanical properties of TPVs were also improved with the increasing MgMA content.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）