JOURNAL OF NON-CRYSTALLINE SOLIDS
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2025
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IF 3.5
Han Zeng,Maoqiang Bi,Zhonghe Tong,Yingtai Du,Xi Chen,Tianyan Jiang
In this study, the enhancement mechanism of SiO 2 modified by different silane coupling agents (SCA) on the moisture resistance, thermal properties and electrical insulation properties of epoxy resin (EP) composites is discussed. Through the combination of experimental tests and molecular dynamics (MD) simulations, the performance differences of five systems (EP, SiO 2 -EP, KH550 / SiO 2 -EP, KH560 / SiO 2 -EP, KH570 / SiO 2 -EP) in water absorption, glass transition temperature ( T g ) and volume resistivity are analyzed. The changes of free volume fraction (FFV), interaction energy, number of hydrogen bonds and diffusion behavior of water molecules are revealed from the microscopic point of view. The experimental results show that the introduction of modified SiO 2 significantly improves the moisture resistance, thermal properties and electrical properties of EP. Among them, KH550 modified SiO 2 has the best effect, T g increases by 12.3 %, volume resistivity increases by 22.1 %, and water absorption rate decreases by 21.9 % at 60 °C. MD simulations further confirm that the nano-SiO 2 modified by SCA can effectively limit the diffusion of water molecules and reduce the effect of temperature on the mean square displacement (MSD) of the system. The KH550 / SiO 2 -EP system has the smallest free volume and the highest number of hydrogen bonds, which effectively inhibits the diffusion of water molecules and the movement of molecular chains. This study provides a theoretical basis and material design strategy for the application of epoxy composites in hygrothermal environments.
研究领域:
高分子材料科学
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复合材料工程
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电气绝缘技术
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材料化学
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纳米功能材料
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2023
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IF 5.9
Hang Shen,Zhihao Wu,Ruiyang Dou,Limin Jiao,Geng Chen,Mingzhang Lin,Wei Huang,Qiang Liu,Hongbing Chen
The developing nuclear technology has increased the need for radiation-resistant and shielding materials. It is crucial to study the radiation resistance of polymers in order to prevent safety incidents brought on by the degradation of polymer performance in a nuclear environment. In this work, γ-aminopropyltriethoxy silane (KH550) was successfully grafted onto carbon-doped boron (BCN) to obtain modified BCN (BCN-KH550), then BCN-KH550 was added in silicone rubber and refined and vulcanized. The elongation at break of silicone rubber composite doped with 0.3 phr BCN-KH550 can retain (54 ± 2)% of the initial value. The addition of BCN and BCN-KH550 both increases the initial decomposition temperature of the irradiated SR. The radiation caused changes in crystallinity and glass transition temperature (T g ) were measured using differential scanning calorimetry. The difference T g of BCN-KH550/SR0.3 before and after irradiation is 0.9 °C higher than that of SR. It is supposed that BCN protects the side group of SR during irradiation through differential thermogravimetric analysis curve and gas phase infrared spectra of the irradiation-induced gas products. BCN and BCN-KH550 can lower the hydrocarbon, CO 2 and CO production by side chain breakdown in both air and nitrogen atmospheres. The presence of BCN and BCN-KH550 decrease the radiation crosslinking of SR. The outcomes demonstrate that BCN-KH550 can reduce the effects of γ-radiation crosslinking on SR by declining side chain decomposition.
研究领域:
材料科学
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核工程
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高分子科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Lei Zhang,Jie Zhang,Chao Lv,Li Gao,Shupin Luo,Yiping Ren,Liang Chang,Xueqi Chen,Qiheng Tang,Wenjing Guo
The primary purpose of this work is to study the fabrication of a flexible natural cellulosic fiber composite. In this respect, natural cellulosic fiber was obtained by modified poplar wood fiber through sodium hydroxide (NaOH) and γ-Aminopropyl Triethoxysilan. Then, the composites were fabricated by hot-pressing the modified wood fibers and polyurethane following characterization. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) observation results confirmed that some of the hemicellulose and lignin were removed from wood fibers after NaOH modification and successfully grafted with alkoxy structures after KH550 modification. NaOH&KH550 modification improved the interfacial compatibility between poplar wood fibers and polyurethane. The flexibility of the composites was improved (the slenderness value was reduced by 113 %), allowing flexible deformations such as bending, twisting, and knotting. In addition, thermal stability , tensile strength (increased by 105 %), elongation at the break (increased by 125 %), and water resistance were increased. This flexible natural cellulosic fiber composite is expected to be applied in the veneering of curved materials and special-shaped structure furniture, providing a theoretical basis for improving the added value of wood-based composites.
研究领域:
材料科学
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木材科学与技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
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2023
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IF 2.2
Tuo Liang,Jirui Hou,Jiaxin Xi
Recently, much attention has been directed toward nanofluids’ applications for enhanced oil recovery (EOR). Here, amphiphilic molybdenum disulfide (KH550-MoS2) nanosheets are synthesized using a hydrothermal approach. The physicochemical properties and EOR potential of ultralow concentration KH550-MoS2 nanofluids are systematically investigated at Changqing Oilfield (China) reservoir conditions (temperature∼55 °C and salinity∼7.8 × 104 mg/L). Interfacial tension (IFT), wettability alteration and emulsion stability are characterized to evaluate the physicochemical properties of KH550-MoS2 nanofluids. The results show that ultralow concentration KH550-MoS2 nanofluid (50 mg/L) can decrease IFT to 2.6 mN/m, change contact angle (CTA) from 131.2° to 51.7° and significantly enhance emulsion stability. Core flooding experiments are conducted to determine the dynamic adsorption loss law and oil displacement efficiency of KH550-MoS2 nanofluid. Results indicate that the cumulative produced KH550-MoS2 nanosheets ratio to total injected KH550-MoS2 nanosheets (CNR) reaches 91.5% during flooding in a low permeability reservoir. Moreover, ultralow concentration KH550-MoS2 nanofluid can increase oil displacement efficiency by 14% after water driven. This work offers a new amphiphilic nanofluid with high efficiency for EOR.
研究领域:
石油工程
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
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2021
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IF 3.512
Minhui Pang,Qiang Zuo,Bing Cao,Hongyan Li,Lina Liang,Lixia Li
Bio-based polyurethane (PU)-coated controlled release fertilizers are attracting a lot of attention; however, generally they have poor properties, so it is difficult for them to meet the agricultural needs. Herein, γ-aminopropyl triethoxy silane (KH550) was first used with nanosilica (NS) to prepare bio-based PU nanocomposite-coated urea (KSPCU). The coating microstructures and nutrient controlled release behaviors of KSPCU were investigated and compared with those of unmodified NS containing PU nanocomposite-coated urea (SPCU) and bio-based PU-coated urea (PCU). The KSPCU with KH550 exhibited an excellent controlled release performance. Its nutrient release longevity exceeded 105 d, which was nearly 6 times greater than that of PCU and 2 times more than that of SPCU, and it was much longer than that of PCU reported in previous research at a coating rate of 3 wt %. A series of characterization methods combined with water resistance capacity and porosity measurements confirmed that a hydrogen bond was formed by the reaction between the nanoparticle and PM200, the nanoparticle was bonded on the macromolecular chain, and KH550 in the coating increased the cross-linking degree, which were beneficial to slowing down the nutrient release of the KSPCU. The innovative application of KH550 on bio-based PU-coated fertilizers will provide a new coating technology for improving their controlled release property.
研究领域:
农业科学
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材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
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2016
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IF 3.85
Chen Pan,Kaichang Kou,Qian Jia,Yu Zhang,Guanglei Wu,Tiezheng Ji
To achieve polymer-based composites for electronic packaging with low dielectric constant, low dielectric loss tangent and high thermal conductivity , silane coupling agent KH550 modified hexagonal boron nitride (hBN) platelets were introduced into PTFE matrix via a cold pressing and sintering method. The effect of surface treatment on the morphology, thermal conductivity and dielectric properties of the composites was investigated. The results revealed that after surface treatment, the interfacial adhension between hBN platelets and PTFE matrix was improved and the in-plane orientation degree of hBN platelets in PTFE matrix decreased, which effectively improvd the thermal conductivity of the composites. The thermal conductivity of hBN-KH550/PTFE composite with 30 vol% filler content is 0.722 W/mK, which is 2.7 folds of pure PTFE. Moreover, the enhanced interfacial adhension and reduced surface hydrophilicity of hBN platelets significantly decreased the interfacial polarization , resulting in not only lower dielectric constant and dielectric loss tangent but also weaker frequency-dependence.
研究领域:
材料科学
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复合材料
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电子封装
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热管理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）