IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
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2025
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IF 3.1
Zuhao Wang,Xiao Peng,Ioannis Chronis,Yingrui Wu,Constantinos S. Psomopoulos,Chao Tang
As the global power industry evolves, transformer insulation systems face increasing challenges. The aging of cellulose insulation paper (cellulose-IP) at elevated temperatures significantly impacts its insulation properties and overall lifespan. To enhance the thermal aging resistance and industrial usability of cellulose-IP, this study employs nano-boron nitride (h-BN) along with three silane coupling agents—3-ammonopropyltriethoxysilane (KH550), 3-glycidyloxypropyltrimethoxysilane (KH560), and 3-methacryloyloxypropyltrimethoxysilane (KH570)—to modified cellulose-IP. Upon evaluating the properties and simulation results of the modified cellulose-IP, KH550-hBN demonstrated superior properties and was selected for an accelerated thermal aging test lasting 60 days. The results indicated that KH550-hBN effectively mitigates the degradation of cellulose-IP. In the late aging stage, the mechanical properties of the modified cellulose-IP deteriorated more slowly than those of pure cellulose-IP. Additionally, thermal conductivity improved by 26.9%, while breakdown field strength increased by 12.1%. The introduction of KH550-hBN promotes the formation of a complete thermal conductivity network within the cellulose matrix, increases the number of intermolecular hydrogen bonds and introduces nano-barrier regions.These improvements enhance the interactions between the cellulose systems and effectively inhibit the generation and migration of polar derivatives during the aging process, resulting in a significant improvement in the longevity and stability of transformer internal insulation systems.
研究领域:
材料科学
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电气工程
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DOI
高影响因子
CELLULOSE
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2019
·Vol. 26
·期 12
·7451-7468
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IF 3.917
Mo Yang,Yang Lijun,Hou Wei,Zou Tiantian,Huang Youyu,Zheng Xiaoling,Liao Ruijin
Abstract This study aims to decrease the dielectric constant of cellulose insulating paper by octa(aminophenyl)silsesquioxane (OAPS) grafting. OAPS was grafted onto the primary hydroxyl group of cellulose molecules via amino groups and epichlorohydrin. The dielectric constant and dielectric loss of insulating paper before and after modification were investigated. Relative to the unmodified paper, the dielectric constant of 15 wt% OAPS-grafted paper decreased from 5.27 to 4.28, and the dielectric loss decreased by 37.5% at 50 Hz. The movement and orientation polarization of the cellulose chains could be restricted due to the porous macromolecular structure and nano quantum interface effect produced by OAPS, thereby resulting in the reduction of cellulose polarizability. Moreover, the OAPS grafting modification does not degrade the other properties of cellulose insulation, i.e., its thermal stability, mechanical performance, fire-resistant properties, and electrical strength. OAPS grafting has promising potential application for preparing low dielectric constant insulating paper. Graphic abstract
研究领域:
材料科学
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电气工程
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2025
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IF 7.4
Meng Huang,Zilu Wang,Yuanxin Yao,Jian Gao,Bo Qi
The service life of oil-immersed transformers is closely linked to the durability of insulation pressboard, which is often compromised by thermal aging during prolonged high-temperature operation. To enhance the thermal stability of cellulose insulation pressboard, this study proposes a modification technique based on aminosilane treatment. The modified pressboard is characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and mercury intrusion porosimetry (MIP). The combined results confirm that aminosilane grafts amino groups onto the cellulose fibers and forms a cross-linked network among them. Compared to the unmodified insulation pressboard, the aminosilane-modified insulation pressboard exhibits a 7.42 % decrease in dielectric constant and a 7.42 % increase in elongation at break. The contact angle increases from 75.7° to 99.4°, indicating enhanced hydrophobicity. Aminosilane modification enhances the thermal stability of the insulation pressboard. Throughout the aging process, the modified pressboard consistently demonstrates superior performance in key metrics such as degree of polymerization (DP), dielectric properties, and mechanical strength. After 30 days of thermal exposure, the modified pressboard exhibits a 44.14 % increase in DP, a 7.76 % decrease in dielectric constant, and a 2.3 % improvement in elongation at break relative to the reference sample.
研究领域:
电气工程
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材料科学
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高分子科学
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化学工程
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DOI
高影响因子
IEEE Access
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2019
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IF 4.098
Yang Mo,Lijun Yang,Tiantian Zou,Wei Hou,Ruijin Liao
Kevlar pulp treated with low-temperature plasma and nano cellulose fibrils (NCFs) have been introduced as reinforcements in the preparation for composite insulating paper with low relative permittivity, dielectric loss, good mechanical properties, and thermal stability. More polar groups of Kevlar fibers could be exposed after plasma treatment. Results showed that the relative permittivity of the composite paper containing 20% Kevlar pulp, 10% NCF, and 70% softwood pulp is decreased by 29.6% and the dielectric loss is decreased by 43.2% at 50 Hz, 25°, compared with the conventional paper formed by pure softwood pulp. The change was due to the introduction of Kevlar pulp with intrinsic low dielectric constant and loss, which decreases the whole polarizability of the paper. The mechanical properties of the composite paper became worse after introducing 20% Kevlar pulp. About 10% NCF can work as a mechanical reinforcement to compensate for the tensile and Yang's modulus loss. Scanning electron microscopy results showed that NCF could fill the void defects and improve the interface bonding of the fibers to enhance the paper mechanical properties. The composite paper also had better insulating and thermal properties than the conventional paper. It has been concluded that the Kevlar pulp/NCF/softwood pulp composite paper has the potential to replace the pure softwood paper for the application of high-voltage ac transformer insulation.
研究领域:
材料科学
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电气工程
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复合材料
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绝缘技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）