MOLECULES
·
2024
·Vol. 29
·期 23
·5522
·
IF 4.2
Gen Liu,Faxin Du,Zhangjun Yao,Guangzhao Li,Wen Kuang,Chongyu Zhu,Yi Liu,Honglin Chen,Fumei Wang,Ce Zhou,Xueli Wei,Wenyan Wang,Rui Han
Integrating rubber with superior low-temperature capabilities, such as ethylene propylene diene monomer (EPDM), is a strategic approach to bolster the low-temperature performance of fluoroelastomer (FKM). However, FKM and EPDM are thermodynamically incompatible. This work synthetized three EPDM-based polar macromolecular compatibilizers, epoxidized EPDM (EPDM-EP), 2,2-trifluoroethylamine-grafted epoxidized EPDM (EPDM-TF), and 2,4-difluorobenzylamine-grafted epoxidized EPDM (EPDM-DF), to enhance the compatibility between FKM and EPDM. These compatibilizers were subsequently incorporated into FKM/EPDM rubber blends. The results revealed that the glass transition temperature (Tg) of FKM/EPDM decreased by 1.3 °C, 2.68 °C, and 2.78 °C, respectively, upon the addition of 10 phr of EPDM-EP, EPDM-TF, or EPDM-DF. Moreover, the Tgof the two phases converged. The tensile strength, elongation at break, and tear strength of the FKM/EPDM rubber blends were also enhanced by the inclusion of these compatibilizers. Notably, EPDM-TF and EPDM-DF exhibited remarkable compatibilization effects due to an increase in polarity. This research not only sheds light on the potential for developing new compatibilizers but also paves the way for innovative applications of FKM and its derivatives.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Wenjie Tan,Yili Wei,Yiwen Zhang,Ping Shen,Hua Tu,Yurou Chen,Jun Li,Shun Wang,Yadong Wu,Huile Jin
To improve the interfacial interaction between natural sepiolite (SEP) and fluororubber (FKM), an acid-activated sepiolite (GSEP) was prepared by modifying the natural SEP in inorganic acid solution. The GSEP appear fine needle-like nanostructures and has relatively higher specific surface area (181 %), maximum N 2 adsorption capacity (218 %), and purity compared to SEP. The silanol groups on GSEP formed Si-C bonds with FKM, which increased the cross-linking density of the composites, thus enhancing the mechanical and thermal conductivity of the FKM. Compared to FKM, the tensile strength, modulus at 100 % strain, hardness and initial decomposition temperature of the FKM/GSEP-15 were increased by 259 %, 150 %, 11.7 % and 14.5 °C, respectively. This work provides a new strategy for preparation of high performance FKM with high heat dissipation and high mechanical properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·
IF 12.1
Jiahao Yu,Yong Kou,Hongbing Lei,Qiangqiang Lu,Lei Xiao,Hongyu Yang,Xuran Xu,Junqing Yang,Wei Jiang,Gazi Hao
Ammonium perchlorate (AP) plays an important role in solid propellants because of its high specific impulse, high energy density and low cost. However, the excellent performance cannot conceal the many shortcomings of AP, and the problems of non-concentrated exothermic, high sensitivity and hygroscopicity still seriously impede its application in solid propellants. In this study, the solvent evaporation method is used to directionally modify the order of the cupric oxide (CuO) and fluororubber (F 2603 ) shell layers so as to obtain AP-based composites with different core-shell structures. The interlayer binding energies of the composites with different structures are explored by theoretical calculations, and it is demonstrated that AP-based composites have excellent stability. In addition, CuO with valence-band holes not only reduces the peak temperature of the high temperature decomposition of AP (440.4 to 354.5 °C), but also enhances its combustion properties by undergoing thermite reaction with Al. Furthermore, the excellent hydrophobicity and barrier properties of F 2603 greatly strengthened the hydrophobicity and mechanical properties of the AP-based composites and reduced their sensitivity. In summary, the core-shelled structures AP-based composites prepared by this strategy possessed 5-in-1 excellent properties, which provided a new idea for targeted modulation of the properties of energetic materials.
研究领域:
材料科学
·
推进剂技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Ranran Qi,Ziwen Gan,Qi Wang,Xiaojie Zhang,Mingyi Liao
In this study, microwave (MW)-assisted oxidative degradation of poly(vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene) (P(VDF-TFE-HFP)) was applied to synthesize carboxy-terminated liquid fluororubber, referred to as LTCFs-246. The resulting product has a carboxyl content of 3.01%, a number-average molecular weight (Mn) of 2100 g/mol, and a polydispersity index (PDI) of 1.61. The product's structure was characterized and analyzed in detail using techniques such as 19 F NMR, UV–Vis, and FTIR spectroscopy. Results indicate that the selective dehydrofluorination reaction (K HF reaction) primarily occurs on four sequence structures: HFP-VDF-HFP, HFP-VDF-TFE, TFE-VDF-HFP, and TFE-VDF-TFE, with similar degrees of reactivity across these structures. Two types of C=C bonds were formed in the LTCFs-246 backbone, primarily through Hofmann elimination and, to a lesser extent, Zaitsev elimination. The oxidative reaction (K C-C reaction) was temperature-dependent. At lower temperatures, H 2 O 2 decomposed slowly, limiting the K C-C reaction; as the temperature increased, H 2 O 2 rapidly decomposed, actively engaging in the K C-C reaction and extensively consuming C=C bonds. Once H 2 O 2 was fully consumed, the K C-C reaction ceased, while the K HF reaction continued uninterrupted. In conclusion, this study provides strong evidence to advance the understanding of the oxidative degradation mechanism of MW-assisted P(VDF-TFE-HFP).
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2025
·
IF 6.2
Yang Chen,Junfei Ou,Tianyu Yang,Baozhong Zhu,Yunlan Sun
The restricted energy release efficiency has been a significant hindrance to the utilization of boron (B) powder as a fuel in solid propellants because of the presence of oxidation film on the B surface. To address this issue, poly (vinylidene fluoride-co-hexafluoropropylene) (Viton A) and glycidyl azide polymer (GAP) were used for the collaborative modification of micron-sized boron (µB) powder. The thermal oxidation, ignition, and combustion performance of µB before and after modification were investigated by thermogravimetric-differential thermal analysis (TG-DTG), differential scanning calorimetry (DSC), and carbon dioxide laser ignition testing. The dual-layer coating interface structure of B@Viton A@GAP is more conducive to reducing the ignition delay time, accelerating the flame expansion rate, enhancing the combustion intensity, improving the combustion efficiency, and reducing agglomeration of combustion products of B powder. The study offers an effective method to promote the combustion of B through its modification with Viton A and GAP.
研究领域:
材料科学
·
燃烧与推进
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2024
·
IF 8.1
Zhukang Bai,Yadong Wu,Jun Li,Shun Wang,Xuqiang Peng,Huile Jin
To attain the high dispersion and strong interfacial bonding of TiO 2 in fluororubber (FKM), a novel “core–shell” structured SiO 2 @TiO 2 nanofillers was designed and synthesized by in-situ polymerization and grafting modification method. For the “core–shell” structured SiO 2 @TiO 2 nanospheres , the rough and irregular silica shell can improve the surface area of the SiO 2 @TiO 2 filler and realize the mechanical riveting with the FKM, which shows a significant mechanical properties enhancement function. Compared with the pristine FKM, the tear strength , tensile strength , hardness, modulus at 100% strain, modulus at 300% strain, and storage modulus at −100 °C of FKM/SiO 2 @TiO 2 enhanced by 42.4%, 196.9%, 10%, 24.4%, 66.7%, and 15.5%, respectively. The sample’s electrical, thermal, and color properties were also improved and showed the highest haze and lowest light transmissions. Such a simple and effective method of preparing “core–shell” structured SiO 2 @TiO 2 nanofillers provides great potential in industrial applications.
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
POLYMER COMPOSITES
·
2024
·
IF 4.8
Zhihao Wu,Hang Shen,Yi Wang,Limin Jiao,Yizhi Chen,Xinglong Gong,Mingzhang Lin
Fluorine rubber (FKM) stands as a pivotal sealing material extensively employed in aerospace and nuclear industries. However, its efficacy will be seriously affected by ionizing radiation. Enhancing its radiation resistance becomes imperative to uphold the stability and safety of associated equipment. This study introduced hexagonal boron nitride ( h -BN) into the FKM as radioprotective fillers through mechanical blending. The interfacial interaction between matrix and h -BN, the mechanical performances, thermal properties, and radiation stability of composites were systematically examined. Noteworthy findings highlight the presence of robust interaction forces between h -BN and the matrix, leading to increased crosslink density and improved mechanical properties. The tensile strength of composite with 10 phr fillers (BN/FKM-10) increased by 30% compared to that of pure FKM. Simultaneously, the introduction of h -BN greatly enhanced thermal conductivity and radiation stability. The absorbed dose required to achieve a 50% reduction in elongation at break of BN/FKM-10 surpassed that of FKM by 1.69 times. These results underscore the potential of incorporating h -BN to simultaneously enhance the mechanical performance, thermal property, and radiation resistance of fluorine rubber. Highlights The chemical interaction force between h -BN and FKM was confirmed. FKM composites tensile strength was enhanced by h -BN as an additive crosslinker. The incorporation of h -BN improves FKM composites thermal conductivity. The radiation resistance of FKM composites has been improved with h -BN.
研究领域:
材料科学
·
航空航天工程
·
核工业技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 51
·期 12
·6975-6985
·
IF 2.047
Ma Chaofan,Shen Jun,Tan Liming,Deng Jinzhao,Zeng Chengzong
Ga-based liquid metal (LM) with high thermal conductivity is considered to be a promising thermal interface material (TIM) for electronic thermal devices; however, its pump-out and easy oxidation hinder its popularization. Herein, fluororubber (FKM) was selected as the sealing material to prevent the pump-out of eutectic Ga-In-Sn (EGaInSn) and reduce its oxidation during long-term extreme service conditions. After being placed in an oil bath at 125°C for 4 weeks, the FKM soaked in EGaInSn could still hinder the penetration of EGaInSn and maintain good elasticity and plasticity. When EGaInSn was applied to a radiator cap as TIM, the maximum radiator temperature at full load was 47% lower than that without TIM, and 14% lower than that with commercial thermal grease. Moreover, after experiments including 1000 h of high-temperature aging, 1000 h of constant temperature and humidity, and 1000 thermal shocks, there was no pump-out or apparent oxidation in the sealing structure with FKM.
研究领域:
材料科学
·
电子工程
·
热管理技术
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Jingyan Wang,Yaning Li,Zhiwei Han,Saichao Song,Jian Li
Oxidants, such as oxygen, cannot easily approach the core Al due to the presence of dense alumina on the surface of aluminum particles, thereby resulting in high ignition temperature and long ignition duration. To overcome this challenge, we employed the solvent/non-solvent method using Viton A (a copolymer of 1,1-difluoroethylene and hexafluoropropylene) as a coating material to prepare the core-shell Al/Viton A composite particles . An orthogonal experiment was designed to identify the optimal preparation parameters by evaluating the peak pressure in a closed vessel. The sample with the largest peak pressure was compared with raw Al and Al/Viton A (prepared by the physical mixing method) using the combustion pressure and open combustion tests to evaluate the solvent/non-solvent method. The results from the orthogonal experiment revealed that the water bath temperature exhibited the greatest influence on the coating effects. The composite prepared under a water bath temperature of 55 °C and a stirring rate of 250 rpm, using 20 mL of acetone and a 5 mL/min dripping rate of the Viton A acetone solution, were uniformly coated by Viton A, and exhibited excellent combustion characteristics. In addition, the sample generated using the optimal preparation parameters burnt more vigorously and rapidly than raw Al and Al/Viton A. Finally, the reaction molecular dynamics simulation was employed to gain insight into the effect of Viton A on the combustion of Aluminum particles at the molecular level.
研究领域:
材料科学
·
燃烧化学
✓ 已验证
DOI
高影响因子
ADVANCED ENGINEERING MATERIALS
·
2021
·Vol. 23
·期 5
·2001252
·
IF 3.862
Dawei Zheng,Tianwei Huang,Bing Xu,Xu Zhou,Yaofeng Mao,Lin Zhong,Bing Gao,Dunju Wang
The development of 3D printing technology provides a new idea for the application of energy-containing materials as functional reactive materials, which helps Al–F high-energy materials to achieve customized performance and structure, so that energy transmit can be targeted. A high fuel-load ink (up to 90 wt%) based on Al-polytetrafluoroethylene (PTFE) is designed and fabricated using fluororubber (FR) as a binder. The content of FR is directly related to the mechanical properties of ink, and the customized structure from the uniform and stable deposition can be obtained by adjusting the content of FR (10–20 wt%). Under the display of high-speed photography, the ink shows a strong stability in combustion performance, which is conducive to realize the performance customization of the ink in the application. To better understand the combustion mechanism, the thermal properties and combustion process are analyzed in brief through thermal analysis and the combustion snapshots.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FLUORINE CHEMISTRY
·
2017
·
IF 2.101
Donghan Li,Mingyi Liao
This study evaluates the dehydrofluorination mechanism, structure and thermal stability of pure fluoroelastomer which was dissolved by organic solvent and reacted with different concentrations of KOH at 20 ∼ 60 °C. The sequence types and contents of double bonds and other oxygen-containing groups of samples were analyzed and investigated by Attenuated total reflectance/Fourier transform infrared (ATR-FTIR), 1 H nuclear magnetic resonance (NMR), 19 F-NMR spectroscopy and chemical titration method; thermal decomposition temperatures of samples were analyzed by thermogravimetric analysis (TGA). The results revealed that dehydrofluorination of fluoroelastomer would accompain with oxidation reaction whereby some double bonds conforming to Hofmann’s rule had been converted to hydroxyl groups, wherein the temperature and alkali concentration were the important factors. The double bonds generated in seven positions of molecular chains, sequence types were mainly conformed to Hofmann’s rule and Zaitsev’s rule supplemented. With the increase of reaction temperature and concentration of KOH, the thermal stability of fluoroelastomer decreased obviously since hydroxyl groups had a greater effect on it. Finally, the mechanism of reaction was also deduced.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Defence Technology
·
2025
·
IF 5.9
Liu Yang,Liu Yuezhou,Gao Fulei,Liu Yingzhe,Wang Yinglei
Boron has attracted increasing attention in the field of high-energy explosives and propellants due to its high volume calorific value and mass calorific value. However, the complicated combustion process and low combustion efficiency hinder its wide application. To tackle this challenge, bioinspired polydopamine (PDA) interface reinforced boron-Viton composites, with high structure stability and excellent energy releasing efficiency, are designed and prepared, combining the interface regulation of PDA biomimetic materials and combustion promotion of fluoropolymers. Firstly, the stronger adsorption energy of PDA with boron compared to Viton was demonstrated by molecular dynamics simulations. Next, B@PDA@Viton is prepared by the combination of in-situ dopamine polymerization and solvent-non-solvent methods, and the double-layer core-shell structure is confirmed by XPS, FTIR, and TEM characterizations. TG-DSC analysis shows that B@PDA@Viton possesses superior thermal properties, with a 55.48% increase in oxidation heat compared to raw B. Furthermore, ignition and combustion performance tests indicate that B@PDA@Viton reduces ignition delay by 57.56% and increases heat of combustion by 68.63% relative to raw B. These findings elucidate the ignition and combustion mechanisms of B@PDA@Viton. This work not only developed high-performance boron-based composite fuels but also provides insights into the development of boron-based fuels.
研究领域:
材料科学
·
化学工程
·
能源材料
·
燃烧技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）