MOLECULES
·
2020
·Vol. 25
·期 17
·3794
·
IF 3.267
Yu-Wei Fu,Yong-Qi Zhang,Wei-Feng Sun,Xuan Wang
In order to inhibit the outward-migrations of photo-initiator molecules in the ultraviolet-initiated crosslinking process and simultaneously improve the crosslinking degree and dielectric properties of crosslinked polyethylene (XLPE) materials, we have specifically developed surface-modified-SiO2/XLPE nanocomposites with the silica nanofillers that have been functionalized through chemical surface modifications. With the sulfur-containing silanes and 3-mercaptopropyl trimethoxy silane (MPTMS), the functional monomers of auxiliary crosslinker triallyl isocyanurate (TAIC) have been successfully grafted on the silica surface through thiol–ene click chemistry reactions. The grafted functional groups are verified by molecular characterizations of Fourier transform infrared spectra and nuclear magnetic resonance hydrogen spectra. Scanning electronic microscopy (SEM) indicates that the functionalized silica nanoparticles have been filled into polyethylene matrix with remarkably increased dispersivity compared with the neat silica nanoparticles. Under ultraviolet (UV) irradiation, the high efficient crosslinking reactions of polyethylene molecules are facilitated by the auxiliary crosslinkers that have been grafted onto the surfaces of silica nanofillers in polyethylene matrix. With the UV-initiated crosslinking technique, the crosslinking degree, insulation performance, and space charge characteristics of SiO2/XLPE nanocomposites are investigated in comparison with the XLPE material. Due to the combined effects of the high dispersion of nanofillers and the polar-groups of TAIC grafted on the surfaces of SiO2nanofillers, the functionlized-SiO2/XLPE nanocomposite with an appropriate filling content represents the most preferable crosslinking degree with multiple improvements in the space charge characteristics and direct current dielectric breakdown strength. Simultaneously employing nanodielectric technology and functional-group surface modification, this study promises a modification strategy for developing XLPE nanocomposites with high mechanical and dielectric performances.
研究领域:
材料科学
·
电气工程
·
高分子化学
✓ 已验证
DOI
高影响因子
POLYMER BULLETIN
·
2024
·Vol. 81
·期 12
·10645-10657
·
IF 3.1
Sun Wu-Ji,Liu Xiong-Jun,Yuan Li-Juan,Xiao Han,Lu Jian-Mei
High voltage AC/DC cables require thicker insulation to ensure excellent insulation performance. Selecting the appropriate crosslinker to design the crosslink and crystalline structure of XLPE is key to the insulating properties. Although the crystallinity of XLPE has been extensively studied by using X-ray diffraction and differential scanning calorimeters, few researchers have designed in situ experiments to observe its structure. In this paper, we have created an in situ observational experiment to monitor the structural changes of XLPE insulation. XLPE formed by DTAP crosslinker produces lower gas byproducts, which can effectively reduce the degassing time and energy consumption. The test results and COMSOL simulations indicate that the XLPE formed by straight-chain alkane crosslinkers has better mechanical, thermal and electrical insulating properties than cyclic alkane crosslinkers. Our work is of great significance for selecting suitable crosslinker to control the structure of XLPE and determining the production conditions for high-voltage cables.
研究领域:
材料科学
·
高分子科学
·
电气工程
✓ 已验证
DOI
高影响因子
WEAR
·
2025
·
IF 6.1
Jiajia Cen,Kai Chen,Qin Chen,Xinyue Zhang,Cunao Feng,Xiaowei Li,Dekun Zhang,Shirong Ge
The tribological performance of hip joint materials in the synovial fluid is substantially influenced by environmental factors. In this study, the tribological properties of polyether-ether-ketone (PEEK)-highly crosslinked polyethylene (XLPE) hip joint materials were investigated in composite synovial fluids with varying pH conditions, revealing the coupling mechanism between pH and composite synovial fluid components. The lubrication efficacy of the composite synovial fluid under physiological conditions was validated through a 2 million-cycle hip joint simulation test. Results indicated that the coefficient of friction (COF) decreased with the increasing pH, while the wear factor remained stable at pH = 7.5 and pH = 8.0 but decreased progressively at pH = 8.5. Notably, the Fluid C demonstrated significant pH sensitivity, reducing the wear factor by 89.12 % when pH increased from 8.0 to 8.5. Moreover, the results of the hip joint simulation tests were consistent with the sliding tribology tests. The component concentration regulated the lubrication efficiency, with amplified effects during long-term service. Hence, this study elucidated wear mechanisms in “soft-soft” hip joint materials under simulated physiological conditions and provided critical insights for predicting the lifespan of polymer-based artificial joints.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2025
·
IF 4.5
Bo Zhu,Xu Sun,Yu Feng,Ji Liu,Xinyu Tao,Bo Yang
A microcapsule/XLPE composite material based on reversible Diels-Alder(DA) reaction was designed to solve the problem of electro-hydro hybrid tree aging in cross-linked polyethylene (XLPE) cables during long-term operation. Light-water dual-responsive microcapsules were prepared by in-situ polymerization using hyperbranched polysiloxane containing furan functional groups and linear polysiloxane containing furan and maleimide functional groups introduced by C C covalent bond as core materials and urea-formaldehyde resin as wall materials. A series of composites was prepared by regulating the doping concentration of microcapsules, and their insulation properties were tested. The effect of the doping content of microcapsules on the properties of materials was analyzed, and the multiple self-healing mechanism of microcapsule/XLPE composite was revealed. The results show that when the microcapsule doping concentration is 1 wt%, the composite material can self-heal while maintaining the intrinsic insulation performance of XLPE. Under the condition of thermal triggering, the dynamic reconstruction of the reversible bond enables the material to achieve dual repair of water tree and electrical tree damage, and maintains more than 80 % of the insulation performance after three times of damage-repair, which provides a new strategy for the intelligent design and life extension of high voltage cable insulation materials.
研究领域:
高分子材料科学
·
电气绝缘工程
·
功能复合材料
·
智能材料
·
电力电缆技术
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2022
·
IF 9.879
Xiaoli Wu,Yijun Liao,Lin Yao,Yunfeng Zha,Renjie Li,Yong Wang,Dewei Zhao,Site Mo,Wanxia Huang
To develop effective and convenient de/anti-icing methods for electric transmission-lines has remained to be a challenging task. Electrothermal material has emerged as a promising approach, but the investigation of electrothermal material with high breakdown voltage remains sluggish. Herein, a high electrothermal property and voltage resistant graphene/crosslinked polyethylene (XLPE) composite was prepared as a de/anti-icing material via an unconventional non-percolative structure. The isolated rGO sheets contribute to a record-high breakdown voltage of 1050–2600 V. The field emission at high voltage, resulted from the appropriate gap width between rGO sheets in non-percolated structure, enables these composites to generate electric currents and obvious temperature increases of 2–59.7 °C owing to Joule's effect. More importantly, the combined ideal heating performance and breakdown voltage enable the rGO-filled composites to achieve a high de-icing efficiency of 18 min and an effective anti-icing performance at −20 °C at 1100 V. These results pave the way to apply graphene/XLPE composites in transmission-lines de/anti-icing and other fields requiring joule heating at high voltage.
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
COMPOSITE STRUCTURES
·
2023
·
IF 6.3
Xiaoli Wu,Yunyi Li,Ting Yin,Yijun Liao,Site Mo,Wanxia Huang
The aligned CNT-based composite in transverse direction to the alignment is considered as completely insulating and unsuitable for utilization in de-icing system. Here, we have found that the aligned CNT-based composite in transverse direction to the alignment exhibited excellent electrothermal performance at high voltage, for the first time. Furthermore, we compared and investigated the electrical and electrothermal performance of the aligned and random non-percolative CNT/crosslinked polyethylene (XLPE) composites at high voltage. A temperature increase of 7.5–72.7 ℃ at a record high voltage of 900–3100 V is reached for the aligned CNT/XLPE composites. The filed emission at high voltage enables the electron to transfer along the CNTs radial direction , resulting in joule heating for the aligned CNT/XLPE composites in transverse direction to the alignment. Besides, the non-percolative structure contributes a temperature increase of 8.2–40.1 ℃ at a applied voltage of 900–2800 V to random CNT/XLPE composites. The high applied voltages is significantly higher than rGO-based composites. More importantly, effective de-icing and anti-icing performance at high voltage of 900–2800 V are achieved for the random non-percolative and aligned CNT-based composites at −20 ℃. These results demonstrate the potential of applying the CNT/XLPE composites in de/anti-icing system of transmission-lines and other fields requiring joule heating at high voltage.
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
危险品化学品经营许可证（带存储）