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Unlocking the elasticity in ferroelectrics by slight crosslinking
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作者 Fangzhou Li Liang Gao +1 位作者 Linping Wang Ben-Lin Hu 《Chinese Journal of Structural Chemistry》 2025年第3期15-17,共3页
Elastic electronics are increasingly prevalent in information storage,smart sensing and health monitoring due to their softness,stretchability and portability.Wearable electronic devices should possess elasticity and ... Elastic electronics are increasingly prevalent in information storage,smart sensing and health monitoring due to their softness,stretchability and portability.Wearable electronic devices should possess elasticity and stretchability that align with biological tissues.Specifically,their materials should be capable of elastic strain up to 50–80%,while the devices themselves must maintain electric stability under strains that accommodate body movements[1]. 展开更多
关键词 biological tissuesspecificallytheir maintain electric stability FERROELECTRICS health monitoring ELASTICITY information storagesmart sensing elastic electronics crosslinking
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Facile Crosslinking of Hardwood Kraft Lignin for Sustainable Bio-Based Wood Adhesives
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作者 Ega Cyntia Watumlawar Byung-Dae Park +1 位作者 Long Yang Guanben Du 《Journal of Renewable Materials》 2025年第5期829-848,共20页
As the most abundant aromatic bio-based polymer,lignin has great potential as a sustainable feedstock for building crosslinked thermoset polymers as bio-based adhesives.However,the potential of hardwood kraft lignin(H... As the most abundant aromatic bio-based polymer,lignin has great potential as a sustainable feedstock for building crosslinked thermoset polymers as bio-based adhesives.However,the potential of hardwood kraft lignin(HKL)is limited due to its poor crosslinking reactivity.Hence,for the first time,the present study reports the facile oxidation of HKL involving a redox reaction with silver-ammonia complexes([(AgNH3)2]+),primarily focusing on oxidation to produce reactive quinones and promote C-C linkages during reaction.This study aims to increases reactivity of oxidized HKL for effective crosslinking with monoethanolamine(MEA)for the development of bio-based wood adhesives.The characterization,including 13C-nuclear magnetic resonance(NMR)and Fourier transform infrared(FT-IR)spectroscopy,confirms the oxidation reaction,such as the formation of quinones(C=O)and subsequent crosslinking between the oxidized HKL molecules and MEA.Additionally,gel permeation chromatography(GPC)confirms the C-C and C-O linkages with increased molecular weight after oxidation,and is supported by differential scanning calorimetry(DSC)which shows the exothermic reaction due to the crosslinking of the oxidized HKL molecules via condensation to form C-C and C-O linkages.The crosslinked HKL/MEA-based adhesives underwent mild reaction and achieved a maximum dry shear strength of 0.77 MPa,which exceeds the standard requirement of 0.6 MPa.These findings demonstrate not only a one-pot oxidation for improving the reactivity of HKL using silver complexes,but also its facile crosslinking with MEA for sustainable bio-based wood adhesives. 展开更多
关键词 Kraft lignin OXIDATION silver complex crosslinking wood adhesives
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Development of site-selective photo crosslinking between tyrosine and sulfonium in methyllysine readers
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作者 Yingxiao Gao Feng Feng +2 位作者 Ting Luo Yusong Han Mingxuan Wu 《Chinese Chemical Letters》 2025年第10期366-371,共6页
Reader proteins that bind specific methyllysine are important to biological functions of lysine methylation,but readers of many methyllysine sites are still unknown.Therefore,development of covalent probes is importan... Reader proteins that bind specific methyllysine are important to biological functions of lysine methylation,but readers of many methyllysine sites are still unknown.Therefore,development of covalent probes is important to identify readers from cell samples so as to understand biological roles of lysine methylation.Generally,readers bind methyllysine via aromatic cages that contain tryptophan,tyrosine and phenylalanine,that offer a unique motif for selective crosslinking.We recently reported a site-selective tryptophan crosslinking strategy based on dimethylsulfonium that mimics dimethyllysine to crosslink tryptophan in aromatic cages of readers.Since tyrosine is a key residue for binding affinity to methyllysine,especially some readers that do not contain tryptophan residues in the binding pocket.Here we developed strategies of site-selective crosslinking to tyrosine.Ultraviolet(UV)source was applied to excite tyrosine at neutral pH or phenoxide at basic p H,and subsequent single-electron transfer(SET)from Tyr*to sulfonium inside the binding pocket enables selective crosslinking.In consequence,methyllysine readers with tyrosine-containing aromatic cages could be selectively crosslinked by site-specific sulfonium peptide probes.In addition,we expanded substrates from aromatic cages to tyrosine residues of proximate contact with sulfonium probes.The pair of LgBiT and SmBiT exhibited orthogonal crosslinking in complicated cell samples.As a result,we may expand sulfonium tools to target local tyrosine in future investigations. 展开更多
关键词 Lysine methylation Methyllysine readers Dimethylsulfonium TYROSINE Site-selective crosslinking
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Self-crosslinking strategy enabling high-performance inverted inorganic perovskite solar cells with fill factor exceeding 85%
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作者 Zhongyu Liu Xiu Huang +6 位作者 Yuchen Zhao Jianwei Wang Jiaying Liu Chenyu Zhou Hongwei Wang Tian Cui Xiaohui Liu 《Journal of Energy Chemistry》 2025年第9期381-389,I0011,共10页
Inorganic CsPbI_(3)perovskite with superior thermal stability and photoelectric properties has developed into a promising candidate for photovoltaic applications.Nevertheless,the power conversion efficiency(PCE)of CsP... Inorganic CsPbI_(3)perovskite with superior thermal stability and photoelectric properties has developed into a promising candidate for photovoltaic applications.Nevertheless,the power conversion efficiency(PCE)of CsPbI_(3)perovskite solar cells(PSCs)still lags far behind that of both organic-inorganic hybrid counterparts and the theoretical PCE limit,primarily restricted by severe fill factor(FF)and opencircuit voltage(VOC)deficits.Herein,an in-situ self-crosslinking strategy is proposed to construct high-performance inverted inorganic PSCs by incorporating acrylate monomers as additives into CsPbI_(3)perovskite precursors.During the thermal annealing process of perovskite films,acrylate monomers can form network structures by breaking the C=C groups through an in-situ polymerization reaction,mainly anchored at the grain boundaries(GBs)and on the surfaces of perovskite.Meanwhile,the C=O groups of acrylate polymers can favorably coordinate with uncoordinated Pb^(2+),thereby decreasing defect density and stabilizing the perovskite phase.Particularly,with multiple crosslinking and passivation sites,the incorporation of dipentaerythritol pentaacrylate(DPHA)can effectively improve the perovskite film quality,suppress nonradiative recombination,and block moisture erosion.Consequently,the DPHAbased PSC achieves a champion PCE of 20.05%with a record-high FF of 85.05%,both of which rank among the top in the performance of inverted CsPbI_(3)PSCs.Moreover,the unencapsulated DPHA-based device exhibits negligible hysteresis,remarkably improved long-term storage,and operational stability.This work offers a facile and useful strategy to simultaneously promote the efficiency and device stability of inverted inorganic PSCs. 展开更多
关键词 Inverted inorganic perovskite solar cells CsPbI_(3) Additive crosslinking Defect passivation Stability
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A self-adaptive inorganic in-situ separator by particle crosslinking for nonflammable lithium-ion batteries
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作者 Jiarui Yang Jiuzhou Liu +12 位作者 Wenrui Cai Ziyu Zhao Shan Wang Lu He Shanshan Lv Zhiwei Zhu Zhongfeng Ji Guojiang Wen Hua Li Yuanming Zhai Xuewei Fu Wei Yang Yu Wang 《Journal of Energy Chemistry》 2025年第1期469-480,共12页
All-safe liquid-state lithium-ion batteries(ASLS-LIBs) is of great interest as they can potentially combine the safety of all-solid-state batteries with the high performance and low manufacturing cost of traditional l... All-safe liquid-state lithium-ion batteries(ASLS-LIBs) is of great interest as they can potentially combine the safety of all-solid-state batteries with the high performance and low manufacturing cost of traditional liquid-state LIBs. However, the practical success of ASLS-LIBs is bottlenecked by the lack of advanced separator technology that can simultaneously realize high performances in puncturing-tolerability,fire-resistance, and importantly, wetting-capability with non-flammable liquid-electrolytes. Here, we propose a concept of inorganic in-situ separator(IISS) by hybrid-sol physical crosslinking directly onto the electrode surface to address the above challenges. Particularly, the hybrid-sol is designed with silica nanoparticles as the building block and poly(vinylidene difluoride) nanoparticles as the crosslinking agent. The critical factors for controlling the IISS microstructures and properties have been systematically investigated. The advantages of the IISS have been confirmed by its fast wetting with various fireresistant liquid-electrolytes, customizable thickness and porous structures, robust interface with planar or three-dimensional(3D)-structured electrodes, and importantly, unexpected self-adaptability against puncturing. Enabled by the above merits, a fire-resistant ASLS-LIB is successfully assembled and demonstrated with stable electrochemical performance. This sol-crosslinked IISS may open an avenue for the studies on the next-generation separator technology, cell assembling, solid electrolyte processing as well as non-flammable secondary batteries. 展开更多
关键词 Safe liquid-state lithium-ion batteries In-situ separator technology Hybrid-sol physical crosslinking Electrode coating Inorganic nonflammable separator
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Visual outcomes and corneal biomechanical evaluation between LASIK and LASIK combined with accelerated corneal crosslinking
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作者 Li Zhang Yue-Hua Zhou +6 位作者 Xiao-Rui Wang Yan Zheng Cai-Yun Fu Xiu-Mei Song Ya-Bin Hu Yue Wang Chang-Bin Zhai 《International Journal of Ophthalmology(English edition)》 2025年第3期496-503,共8页
AIM:To assess the visual outcomes and corneal biomechanical properties of myopia patients between laser in situ keratomileusis(LASIK)and LASIK combined with accelerated corneal crosslinking(LASIK Xtra).METHODS:This pr... AIM:To assess the visual outcomes and corneal biomechanical properties of myopia patients between laser in situ keratomileusis(LASIK)and LASIK combined with accelerated corneal crosslinking(LASIK Xtra).METHODS:This prospective study analyzed 52 consecutive myopia patients treated with LASIK Xtra and 45 consecutive myopia patients treated with LASIK.Only the right eyes in the two groups were analyzed.The uncorrected distance visual acuity(UDVA),keratometry values,postoperative central corneal thickness(CCT),corneal demarcation line depth,the corneal compensated intraocular pressure(IOPcc),Goldmann-correlated IOP(IOPg),corneal resistance factor(CRF)and corneal hysteresis(CH)from Ocular Response Analyzer(ORA)were analyzed.Further,the correlation between the demarcation line depth and ORA-related biomechanical parameters were analyzed.RESULTS:No significant differences in UDVA,postoperative CCT,or mean K values were found between the 2 groups at 1 to 12mo postoperative follow-up(all P>0.05).The changes of CRF was significantly lower in the LASIK Xtra group compared to the LASIK group(all P<0.05)at all the postoperative visits.The changes of CH were significantly higher in the LASIK Xtra group(all P<0.05).No significant differences were discovered regarding the changes of IOPcc and IOPg posperatively(all P>0.05).Out of 52 cases in the LASIK Xtra group,the demarcation line was present in 40 eyes(77%).The average depth of the demarcation was 220.73±42.70μm(136 to 288μm).No significant correlation was observed between the depth of the demarcation line and any of the ORA-related biomechanical parameters such as IOPcc,IOPg,CRF and CH at 12mo(all P>0.05).CONCLUSION:Both procedures demonstrate comparable outcomes in terms of visual acuity,refraction and ablation predictability.This study confirms that corneal biomechanical properties of the included patients weakened after both procedures,but the cornea after LASIK Xtra are stiffer than conventional LASIK. 展开更多
关键词 MYOPIA femto-laser in situ keratomileusis laser in situ keratomileusis combined with accelerated corneal crosslinking corneal biomechanics
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Highly Hydrolysis-Resistant Polyimide Fibers Prepared by Thermal Crosslinking with Inherent Carboxyl Groups
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作者 Can-Can Zhang Jun-Long Yang +1 位作者 Ya-Jiang Huang Guang-Xian Li 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第2期247-255,I0010,共10页
Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chain... Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments. 展开更多
关键词 POLYIMIDE Carboxyl group crosslinking Hydrolysis-resistance
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Stromal lenticule addition keratoplasty with corneal crosslinking for corneal ectasia secondary to FS-LASIK:a case series
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作者 Li-Xiang Wang Ying-Ping Deng +5 位作者 Meng-Zhen Xie Ke Ma Hong-Bo Yin Qiong Wang Rui Gong Jing Tang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期596-602,共7页
●AIM:To explore the clinical efficacy and safety of stromal lenticule addition keratoplasty(SLAK)with corneal crosslinking(CXL)on patients with corneal ectasia secondary to femtosecond laser-assisted in situ keratomi... ●AIM:To explore the clinical efficacy and safety of stromal lenticule addition keratoplasty(SLAK)with corneal crosslinking(CXL)on patients with corneal ectasia secondary to femtosecond laser-assisted in situ keratomileusis(FS-LASIK).●METHODS:A series of 5 patients undertaking SLAK with CXL for the treatment of corneal ectasia secondary to FS-LASIK were followed for 4-9mo.The lenticules were collected from patients undertaking small incision lenticule extraction(SMILE)for the correction of myopia.Adding a stromal lenticule was aimed at improving the corneal thickness for the safe application of crosslinking and compensating for the thin cornea to improve its mechanical strength.●RESULTS:All surgeries were conducted successfully with no significant complications.Their best corrected visual acuity(BCVA)ranged from 0.05 to 0.8-2 before surgery.The pre-operational total corneal thickness ranged from 345-404μm and maximum keratometry(Kmax)ranged from 50.8 to 86.3.After the combination surgery,both the corneal keratometry(range 55.9 to 92.8)and total corneal thickness(range 413-482μm)significantly increased.Four out of 5 patients had improvement of corneal biomechanical parameters(reflected by stiffness parameter A1 in Corvis ST).However,3 patients showed decreased BCVA after surgery due to the development of irregular astigmatism and transient haze.Despite the onset of corneal edema right after SLAK,the corneal topography and thickness generally stabilized after 3mo.●CONCLUSION:SLAK with CXL is a potentially beneficial and safe therapy for advanced corneal ectasia.Future work needs to address the poor predictability of corneal refractometry and compare the outcomes of different surgical modes. 展开更多
关键词 corneal ectasia femtosecond laserassisted in situ keratomileusis stromal lenticule addition keratoplasty corneal crosslinking corneal thickness corneal biomechanics
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Detecting early changes in choroidal vascularity and thickness using optical coherence tomography in patients with corneal crosslinking for keratoconus
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作者 Selim Doganay Mehmet Omer Kiristioglu +1 位作者 Derya Doganay Elif Kacmaz 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1267-1272,共6页
AIM:To investigate changes in choroidal thickness and vascularity in keratoconus patients treated with corneal crosslinking.METHODS:This study evaluated 28 eyes of 22 patients with keratoconus who underwent corneal cr... AIM:To investigate changes in choroidal thickness and vascularity in keratoconus patients treated with corneal crosslinking.METHODS:This study evaluated 28 eyes of 22 patients with keratoconus who underwent corneal crosslinking.The choroidal thicknesses were evaluated on enhanced depth imaging optical coherence tomography at the preoperative and postoperative 3d,1,and 3mo.Choroidal thickness in the four cardinal quadrants and the fovea were evaluated.The choroidal vascularity index was also calculated.RESULTS:There was no significant difference in central choroidal thickness between the preoperative and postoperative 3d,1mo(P>0.05).There was a significant increase in the 3mo(P=0.034)and a significant decrease in the horizontal choroidal vascularity index on the postoperative 3d(P=0.014),there was no statistically significant change in vertical axes and other visits in horizontal sections(P>0.05).CONCLUSION:This study sheds light on choroidal changes in postoperative corneal crosslinking for keratoconus.While it suggests the procedure’s relative safety for submacular choroid,more extensive research is necessary to confirm these findings and their clinical significance. 展开更多
关键词 KERATOCONUS corneal crosslinking choroidal vascularity index enhanced depth imaging optical coherence tomography
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Immobilization of Thermomyces lanuginosus lipase in a novel polysaccharide-based hydrogel by a two-step crosslinking method and its use in the lauroylation ofα-arbutin
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作者 Ming Chen Weina She +4 位作者 Xin Zhao Cheng Chen Benwei Zhu Yun Sun Zhong Yao 《Bioresources and Bioprocessing》 2024年第1期83-96,共14页
The Thermomyces lanuginosus lipase(TLLs)was successfully immobilized within a novel hydrogel matrix through a two-step crosslinking method.TLLs were initially crosslinked through the Schiff base reaction by oxidized c... The Thermomyces lanuginosus lipase(TLLs)was successfully immobilized within a novel hydrogel matrix through a two-step crosslinking method.TLLs were initially crosslinked through the Schiff base reaction by oxidized carboxymethyl cellulose(OCMC).The water-soluble OCMC@TLLs complex was subsequently crosslinked by carboxymethyl chitosan(CMCSH)in a microfluidic apparatus to form the CMCHS/OCMC@TLLs microspheres.The CD(Circular Dichroism,CD)and FT-IR(Fourier Transform infrared spectroscopy,FT-IR)spectra demonstrated that the crosslinking of TLLs with OCMC resulted in a less significant impact on their structure compared to that with glutaraldehyde.CMCHS/OCMC@TLLs showed decreased catalytic performance due to the mass transfer resistance,while its thermal stability was greatly improved.The CMCHS/OCMC@TLLs were used to catalyze the lauroylation of arbutin in tetrahydrofuran.After 12 h of reaction under optimal conditions,the yield of 6′-O-lauryl arbutin reached an impres-sive 92.12%.The prepared 6′-O-lauryl arbutin has high lipophilicity and exhibits similar tyrosinase inhibitory activity and higher antioxidant activity compared to its parent compound. 展开更多
关键词 ARBUTIN Oxidized carboxymethyl cellulose Carboxymethyl chitosan Microfluidic Covalent crosslinked polymer LIPASE ACYLATION
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含主链和末端炔基交联位点聚酰亚胺树脂的制备与表征
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作者 王进 刘杰 +3 位作者 钟敏 江乾 黄安民 高纪明 《高分子通报》 北大核心 2025年第9期1407-1415,共9页
以间苯二胺(m-PDA)和4,4′-(六氟异丙烯)二酞酸酐(6FDA)为二胺、二酐单体,4,4′-(乙炔-1,2-二基)二酞酸酐(EBPA)为主链交联剂,4-苯基乙炔基邻苯二甲酸酐(PEPA)为封端剂,采用化学亚胺化法在N-甲基吡咯烷酮(NMP)中合成了一系列重复单元数... 以间苯二胺(m-PDA)和4,4′-(六氟异丙烯)二酞酸酐(6FDA)为二胺、二酐单体,4,4′-(乙炔-1,2-二基)二酞酸酐(EBPA)为主链交联剂,4-苯基乙炔基邻苯二甲酸酐(PEPA)为封端剂,采用化学亚胺化法在N-甲基吡咯烷酮(NMP)中合成了一系列重复单元数为2、具有不同含量主链交联活性位点的聚酰亚胺预聚体,并对其结构和性能进行了表征分析。结果表明,由于低分子量以及空间位阻和扭曲结构的贡献,所制备的聚酰亚胺预聚体在一定温度范围内具有良好的熔体流动性,并在330~340℃附近出现最低熔体黏度(5.04~6.80 Pa·s);随着温度的升高,主链和末端炔基都将发生固化反应。经过370℃/2h固化处理的聚酰亚胺树脂具有高玻璃化转变温度(T_(g)=353~380℃),并随着预聚体中主链交联活性位点含量的增加而逐渐升高;在经过380℃/1h后固化处理之后,含主链炔基的预聚体对应树脂的T_(g)出现了6~11℃的提高(高达391℃)。经过热固化处理的聚酰亚胺树脂具有优异的热稳定性,5%热失重温度介于538~546℃之间,10%热失重温度介于563~571℃之间,850℃时的残炭率超过59%。此外,通过对预聚体粉末洗涤工艺的探究,提供了一种可有效去除产物中残留有机杂质的方法。 展开更多
关键词 聚酰亚胺 预聚体 主链交联位点 末端交联位点 热性能
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交联体系对聚合物基PTC复合材料性能的影响论述
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作者 胡洪亮 丁旭 金玉杰 《化工新型材料》 北大核心 2025年第6期10-14,21,共6页
讨论了不同交联体系对正温度系数效应(PTC)材料性能的影响,重点分析了对电阻率、PTC强度和负温度系数效应(NTC)的调控作用。研究表明,适当的交联处理可以优化复合材料的微观结构,构建稳定的导电网络,从而提升PTC性能并显著减弱或消除NT... 讨论了不同交联体系对正温度系数效应(PTC)材料性能的影响,重点分析了对电阻率、PTC强度和负温度系数效应(NTC)的调控作用。研究表明,适当的交联处理可以优化复合材料的微观结构,构建稳定的导电网络,从而提升PTC性能并显著减弱或消除NTC效应。在单一交联体系中,辐照交联通过形成三维交联网络有效抑制高温下导电填料的迁移,增强了材料的热机械稳定性;化学交联则通过基体改性和基体-填料桥连,进一步改善了导电填料的分散性及相容性。双重交联体系结合了辐照和化学交联的优势,展现出更大的潜力,不仅在提升PTC强度方面效果显著,还能有效改善材料的稳定性。 展开更多
关键词 聚合物基正温度系数效应复合材料 交联体系 辐照交联 化学交联
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交联共聚改性有机玻璃的制备及性能研究
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作者 汪海平 刘芸 +1 位作者 张玉敏 胡思前 《塑料科技》 北大核心 2025年第4期27-31,共5页
文章选用甲基丙烯酸甲酯(MMA)作为主单体、甲基丙烯酸(MAA)作为改性单体、乙氧化双酚A二甲基丙烯酸酯(BPA2EODMA)作为交联剂,通过本体聚合方法制备一系列交联共聚改性有机玻璃。采用紫外-可见分光光度计(UV-vis)、差示扫描量热仪(DSC)... 文章选用甲基丙烯酸甲酯(MMA)作为主单体、甲基丙烯酸(MAA)作为改性单体、乙氧化双酚A二甲基丙烯酸酯(BPA2EODMA)作为交联剂,通过本体聚合方法制备一系列交联共聚改性有机玻璃。采用紫外-可见分光光度计(UV-vis)、差示扫描量热仪(DSC)、热重分析仪(TG)及邵氏硬度计等仪器探讨不同体积分数的MAA和BPA2EODMA对改性有机玻璃的透光率、表面硬度、玻璃化转变温度(t_(g))及热稳定性的影响。结果表明,MAA体积分数达到10%时,有机玻璃透明性良好,耐热性显著提升,t_(g)达到144.1℃,硬度达到最大值79.97;MAA过量,有机玻璃透光率下降明显。添加BPA2EODMA交联剂后,t_(g)进一步提升至154.2℃,热稳定性增强,但透光性和硬度有所降低。 展开更多
关键词 有机玻璃 共聚 交联 耐热改性
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钙离子-聚丙烯酰胺交联体系研究
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作者 马涛 伦增珉 +3 位作者 张杰 谭中良 许关利 张锁兵 《胶体与聚合物》 2025年第3期130-133,共4页
交联聚合物在油田开发过程中具有广泛的应用,针对传统金属离子交联剂交联时间短的不足,构建了以钙离子作为交联剂的交联聚合物体系。以交联时间、交联后体系黏度作为指标,分析了温度、钙离子浓度、pH值等因素对交联体系的影响。实验结... 交联聚合物在油田开发过程中具有广泛的应用,针对传统金属离子交联剂交联时间短的不足,构建了以钙离子作为交联剂的交联聚合物体系。以交联时间、交联后体系黏度作为指标,分析了温度、钙离子浓度、pH值等因素对交联体系的影响。实验结果表明:钙离子与助剂共同作用可以对聚丙烯酰胺聚合物进行交联,62-90℃,交联时间5-100天,温度越高交联时间越短;降低助剂的pH值有利于延长交联时间,钙离子浓度在600-1200 mg/L均具有较好的交联效果。钙离子交联聚丙烯酰胺体系具有延长交联时间、强度适中等特点。 展开更多
关键词 钙离子 聚丙烯酰胺 交联剂 交联反应 黏度
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复杂大裂缝地层恶性漏失堵漏剂的研究与现场应用 被引量:1
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作者 臧传贞 刘颖彪 +4 位作者 叶成 戎克生 鲁铁梅 刘凡 都伟超 《应用化工》 北大核心 2025年第3期804-808,共5页
大裂缝及断层恶性漏失有效治理难,严重影响钻井提质增效。“凝胶+水泥”堵漏是解决大裂缝恶性漏失的常用方法,其中凝胶材料是关键,但常规凝胶可泵性和成胶强度难以平衡且抗温性差。对此,研制了一种耐温160℃以上、交联时间1~7 h可控的... 大裂缝及断层恶性漏失有效治理难,严重影响钻井提质增效。“凝胶+水泥”堵漏是解决大裂缝恶性漏失的常用方法,其中凝胶材料是关键,但常规凝胶可泵性和成胶强度难以平衡且抗温性差。对此,研制了一种耐温160℃以上、交联时间1~7 h可控的高强度井下交联堵漏聚合物CLD体系,由0.2%~1.0%凝胶主剂(DMCs-AM-AMPS共聚物),0.4%~1.2%酚醛交联剂,1.0%~3.0%增韧材料(丝瓜瓤+超细碳酸钙)和0.02%稳定剂硫脲组成。体系配制后黏度仅有42 mPa·s、易泵送,抗水基钻井液污染性能较好;交联后凝胶黏弹性强度可达H级,缝板承压实验表明,1~3 mm楔形缝板承压可达6.5 MPa。准噶尔盆地某口预探直井在三开钻遇大裂缝,发生失返漏失,多次桥堵和水泥堵漏均失败,采用“CLD体系+水泥”堵漏工艺,一次堵漏成功,应用前景较好。 展开更多
关键词 井下交联聚合物 可控交联 大裂缝漏失 凝胶堵漏
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耐高温海水基压裂液交联剂的制备与性能
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作者 郭布民 赵健 +5 位作者 鲍文辉 申金伟 许田鹏 潘江浩 张海 刘晓非 《化学工业与工程》 北大核心 2025年第3期27-35,共9页
压裂作业是改善油气层的渗流条件,实现油田增产的重要技术手段。但随着海上油田深部储层的开发,具有延迟交联作用的耐高温耐剪切海水基压裂液成为油气开采的迫切需求。鉴于此,制备了有机硼/有机锆复合交联剂,并通过实验优化调控其延迟... 压裂作业是改善油气层的渗流条件,实现油田增产的重要技术手段。但随着海上油田深部储层的开发,具有延迟交联作用的耐高温耐剪切海水基压裂液成为油气开采的迫切需求。鉴于此,制备了有机硼/有机锆复合交联剂,并通过实验优化调控其延迟交联性能以及耐温耐剪切性能。通过核磁共振波谱、红外光谱和能谱仪表征了交联剂结构,采用吴茵混调器和高温高压流变仪评价了压裂液延迟交联性能和耐温耐剪切性能。结果表明,使用该交联剂的压裂液体系可以通过改变基液pH值来调控延迟交联时间,在60~300 s范围可控,并且压裂液在165℃、100 s^(-1)的条件下剪切120 min的黏度为154 mPa·s,耐温剪切性能满足深海油田开发需求。 展开更多
关键词 海水基压裂液 有机硼 有机锆 延迟交联 耐温耐剪切
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滚塑成型工艺及其制品在体育器材中的应用
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作者 黄磊 陈剑 《合成树脂及塑料》 北大核心 2025年第6期75-78,共4页
滚塑成型作为一种高效生产大型中空塑料制品的工艺,在材料改性、工艺优化及应用拓展方面取得了显著进展。模具内部空气温度最高值和最佳工艺区间是控制滚塑成型制品质量的关键参数,材料厚度、熔体流动速率及炭黑添加量等显著影响气孔消... 滚塑成型作为一种高效生产大型中空塑料制品的工艺,在材料改性、工艺优化及应用拓展方面取得了显著进展。模具内部空气温度最高值和最佳工艺区间是控制滚塑成型制品质量的关键参数,材料厚度、熔体流动速率及炭黑添加量等显著影响气孔消除和力学性能。双叔丁基过氧异丙基苯结合三羟甲基丙烷三丙烯酸酯可使交联高密度聚乙烯交联程度最高达87.3%,滚塑发泡工艺通过熔体黏弹性调控和复合发泡剂体系,可制备泡孔均匀、低密度的高性能聚乙烯。滚塑工艺广泛用于体育器材(如皮划艇、健身球等)的制造,可实现轻量化与高强度的平衡。 展开更多
关键词 滚塑成型 高密度聚乙烯 交联 发泡
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微波预活化对沥青硫化反应的促进作用和工程性质影响研究
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作者 王黎明 庞宏 +2 位作者 孙永卓 董明泽 徐永丽 《材料导报》 北大核心 2025年第14期63-69,共7页
微波加热可以使沥青低温裂化而化学活性增强,理论上有利于硫化交联反应的发生,进而通过改变游离硫与交联硫的比例影响硫改性沥青的工程性质。为分析微波加热预活化对沥青硫化反应和工程性质的影响,开展了微波活化-硫化和直接硫化两种沥... 微波加热可以使沥青低温裂化而化学活性增强,理论上有利于硫化交联反应的发生,进而通过改变游离硫与交联硫的比例影响硫改性沥青的工程性质。为分析微波加热预活化对沥青硫化反应和工程性质的影响,开展了微波活化-硫化和直接硫化两种沥青的对比性试验。在硫化反应方面,通过改进亚硫酸钠氧化-碘滴定法和高温燃烧法分别测定了游离硫和总硫含量,并且通过体视显微镜观察了表面结晶析出状态,发现微波活化-硫化沥青的反应活化能相对降低24%,硫化反应的速度提高,同时有更多游离硫向交联硫转化。在工程性质方面,通过温度扫描、多应力重复蠕变恢复(MSCR)、线性振幅扫描(LAS)、弯曲梁流变(BBR)等沥青流变学试验和旋转薄膜烘箱(RTFO)老化试验,发现微波活化-硫化沥青的模量相对提高且弹性增强,高温时抗车辙能力提高明显,中温时疲劳寿命提高4~6倍,抗低温开裂能力略有改善,耐热氧老化性提高。微波预活化措施使得更多游离硫向交联硫转化,通过强化交联和弱化游离硫的不利影响使沥青胶体结构变得更稳定,是微波活化-硫化沥青工程性质相对改善的根本原因。这种措施高效可行,对其他改性方式也具有潜在效益。 展开更多
关键词 道路工程 沥青 微波活化 硫化 交联反应 工程性质
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基于前端开环易位聚合的本征阻燃聚双环戊二烯的制备及性能研究
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作者 王平 许杰 +5 位作者 胡心芸 杨利 刘文秀 曹田 周意杨 丁运生 《高分子学报》 北大核心 2025年第6期1014-1025,共12页
针对聚双环戊二烯(PDCPD)易燃、聚合工艺复杂且周期长的问题,将阻燃基元9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)引入降冰片烯结构中,设计合成了一种能够与双环戊二烯(DCPD)发生前端开环易位聚合(FROMP)的阻燃单体NB-DOPO,制备了本... 针对聚双环戊二烯(PDCPD)易燃、聚合工艺复杂且周期长的问题,将阻燃基元9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)引入降冰片烯结构中,设计合成了一种能够与双环戊二烯(DCPD)发生前端开环易位聚合(FROMP)的阻燃单体NB-DOPO,制备了本征阻燃PDCPD/NB-DOPO共聚物.研究了NB-DOPO的引入对于共聚体系的前端聚合过程、动态力学性能、热稳定性能、机械性能及阻燃性能的影响,并探究PDCPD/NB-DOPO共聚物的阻燃机理.研究结果表明NB-DOPO能够降低共聚体系的前端聚合速率,并与DCPD发生无规共聚,在保证材料固化度的同时实现可控FROMP.当NB-DOPO的含量低于10%时,高环张力单环烯烃共聚单体的引入促进了交联点的形成,降低了共聚物交联点间分子量(Mc),材料储能模量和机械性能增加.当NB-DOPO添加量达到30%时,PDCPD/NB-DOPO的交联密度降低,但分子链中的刚性结构作为物理交联点,使得材料的机械性能保持的同时,阻燃性能明显提升,材料的极限氧指数(LOI)较PDCPD提高了38%,具有优异的综合性能. 展开更多
关键词 聚双环戊二烯 前端开环易位聚合 本征阻燃 无规共聚 交联密度
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双网络物理交联水凝胶的机械性能与溶胀行为研究
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作者 李鹏 赵静 +4 位作者 余金柱 袁红鹏 张含 梁钰茸 赖小娟 《化学世界》 2025年第2期105-112,共8页
以丙烯酰胺(AM)、丙烯酸(AA)、脂肪醇聚氧乙烯醚丙烯酸酯(C_(18)-PEO_(15)-AC)和二十二烷基二甲基烯丙基氯化铵(DDAC)为单体,制备双网络物理交联网络水凝胶MHAP-15(m)(m代表400 g凝胶中含有C_(18)-PEO_(15)-AC的质量)。通过拉伸测试表明... 以丙烯酰胺(AM)、丙烯酸(AA)、脂肪醇聚氧乙烯醚丙烯酸酯(C_(18)-PEO_(15)-AC)和二十二烷基二甲基烯丙基氯化铵(DDAC)为单体,制备双网络物理交联网络水凝胶MHAP-15(m)(m代表400 g凝胶中含有C_(18)-PEO_(15)-AC的质量)。通过拉伸测试表明,MHAP-15(10 g)的拉伸应力最大,拉伸应力为3.23 MPa,断裂伸长率为1800%左右。MHAP-15(m)水凝胶拉伸和打结拉伸测试表明,该凝胶具有高拉伸强度和恢复性,半径为2.5 mm的圆柱形MHAP-15(2.5 g)水凝胶承受了250 g的重量而不断裂。溶胀性能测试表明水凝胶中所含C_(18)-PEO_(15)-AC的质量对凝胶的吸水溶胀有不同影响,在30℃去离子水中MHAP-15(2.5 g)的吸水溶胀比最高。MHAP-15(2.5 g)水凝胶在质量分数为2%CaCl_(2)、质量分数为2%NaCl、pH=2.1和pH=11.6的水溶液中,溶胀比分别为46.98、206.74、4.97和77.31[m(水)∶m(干凝胶)]。 展开更多
关键词 双网络水凝胶 物理交联 力学性能 溶胀性
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