In the field of power systems,insulating polymers have been found to have extensive applications due to their outstanding properties.However,these materials are susceptible to defects arising from various factors duri...In the field of power systems,insulating polymers have been found to have extensive applications due to their outstanding properties.However,these materials are susceptible to defects arising from various factors during production and operation,which may progress and potentially lead to safety incidents.This paper comprehensively reviews non-destructive testing(NDT)techniques for insulating polymers.Based on the physical principles underlying these methods,they are categorized into electrical testing methods,non-electrical passive testing methods,and non-electrical active testing methods.The paper offers a retrospective assessment of the applications of these methods in insulating polymers.Finally,evaluation of the applicability,advantages,and limitations of these diverse methods is systematically conducted,aiming to facilitate the targeted selection of the optimal NDT method in engineering applications.展开更多
Insulating polymers(commodity plastics in particular)are a major category of polymeric materials widely used in our daily life,but they exhibit abysmal electrical conductivity.Instead,conjugated polymers are gaining t...Insulating polymers(commodity plastics in particular)are a major category of polymeric materials widely used in our daily life,but they exhibit abysmal electrical conductivity.Instead,conjugated polymers are gaining tremendous interest due to their excellent electrical properties and versatile applications in organic electronics.In this perspective,we provide a concise account of the added value in organic solar cells,as brought by the combined use of conjugated and insulating polymers.The challenging tasks and prospective directions are given to the potential benefits of employing insulating polymer additives,which spans from common commodity plastics to high-temperature resistant resins and thermoplastic elastomers.Particularly,the inert polymers can improve many important properties such as mechanical and thermal robustness but not sacrifice optoelectronic performance.展开更多
In integrated circuit packaging,thermal interface materials(TIMs)must exhibit high thermal conductivity and electrical resistivity to prevent short circuits,enhance reliability,and ensure safety in high-voltage applic...In integrated circuit packaging,thermal interface materials(TIMs)must exhibit high thermal conductivity and electrical resistivity to prevent short circuits,enhance reliability,and ensure safety in high-voltage applications.We proposed the thermal-percolation electrical-resistive TIM incorporating binary fillers of both insulating and metallic nanowires with an orientation in the insulating polymer matrix.High thermal conductivity can be achieved through thermal percolation,while electrical non-conductivity is preserved by carefully controlling the electrical percolation threshold through metallic nanowire orientation.The electrical conductivity of the composite can be further regulated by adjusting the orientation and aspect ratio of the metallic fillers.A thermal conductivity of 10 W·m^(-1)·K^(-1)is achieved,with electrical non-conductive behavior preserved.This approach offers a pathway to realizing“thermal-percolation electrical-resistive”in hybrid TIMs,providing a strategic framework for designing high-performance TIMs.展开更多
The multifrequency voltage(MFV)stress,including switching impulses and harmonics,commonly appearing in the modern power system will stimulate the multifrequency impedance dynamics behaviours of electrical insulation.T...The multifrequency voltage(MFV)stress,including switching impulses and harmonics,commonly appearing in the modern power system will stimulate the multifrequency impedance dynamics behaviours of electrical insulation.Therefore,this article presents a novel concept of insulation resilience response(IRR)by employing polymer insulation materials,which may be extended to electrical insulation resilience(EIR).The focus is on understanding reversible recovery performance and supporting physics-informed condition assessment for electrical insulation exposed to MFV.The underlying physical mechanisms and modelling methodologies are integrated to characterise the IRR behaviours of polymer insulation systems.The multifrequency dielectric/impedance properties of different resin dielectrics under diverse temperatures are comparatively investigated as proofofconcept cases.Furthermore,multidimensional sensitivity indicators are developed to quantify the electrical insulation resilience behaviour.A radar plot representation integrating resilience sensitivity indicators qualitatively assesses the IRR behaviours of polymer insulation systems.Additionally,a quantification methodology,including the resilience index(RI)and time-varied RI(TVRI),is proposed for the reversible recovery performance analysis for electrical insulation,respectively.Ultimately,an application-oriented framework derived from TVRI is provided to analyse the recovery performance evolution behaviours of electrical insulation under complex operating conditions.This offers a key theoretical foundation for insulation performance characterisation and condition analysis for high-voltage power equipment.展开更多
Polymer insulating through-silicon-vias （TSVs） is an attractive approach for high-performance 3D integration systems. To further demonstrate the polymer insulating TSVs, this paper investigates the thermal stability...Polymer insulating through-silicon-vias （TSVs） is an attractive approach for high-performance 3D integration systems. To further demonstrate the polymer insulating TSVs, this paper investigates the thermal stability by measuring the leakage current under bias-temperature condition, studies the thermal stress characteristics with Finite Element Analysis （FEA）, and tries to improve the thermal mechanical reliability of high-density TSVs array by optimizing the geometry parameters of pitch, liner and redistribution layer （RDL）. The electrical measurements show the polymer insulating TSVs can maintain good insulation capability （less than 2x 10TM A） under challenging bias-temperature conditions of 20 V and 200~C, despite the leakage degra- dation observation. The FEA results show that the thermal stress is significantly reduced at the sidewall, but highly concen- trates at the surface, which is the potential location of mechanical failure. And, the analysis results indicate that the polymer insulating TSVs （diameter of 10 μm, depth of 50 μm） array with a pitch of 20 μm, liner thickness of 1 μm and RDL radius of 9 μm has an optimized thermal-mechanical reliability for application.展开更多
Record-breaking organic solar cells(OSCs)based on blends of polymer donors and small molecule acceptors often show undesirable degradati on,which severely precludes their practical use.Herei n,we demonstrate a facile ...Record-breaking organic solar cells(OSCs)based on blends of polymer donors and small molecule acceptors often show undesirable degradati on,which severely precludes their practical use.Herei n,we demonstrate a facile and cost-effective approach to con struct thermally stable OSCs at 150℃ by incorporating a small amount of a polymer insulator polyacenaphthylene(PAC)with high glass-transition temperature over 230℃ into polymer:acceptor blends.The model PTB7-Th:EH-IDTBR blend with 10 wt%PAC maintained above 85%of its initial efficiency upon continuous heating at 150℃ for over 800 h,while the efficiency of the blend without PAC sharply dropped by 70%after-300 h.Owing to high miscibility with acceptors,PAC confines the motion of the acceptor molecules and suppresses the acceptor crystallization at elevated temperatures,leading to significantly improved stability.Importantly,the effectiveness of this blending approach was also validated in many other OSC systems,showing great potential for achieving high-performance thermally stable electronics.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 51977117 and 51977118.
文摘In the field of power systems,insulating polymers have been found to have extensive applications due to their outstanding properties.However,these materials are susceptible to defects arising from various factors during production and operation,which may progress and potentially lead to safety incidents.This paper comprehensively reviews non-destructive testing(NDT)techniques for insulating polymers.Based on the physical principles underlying these methods,they are categorized into electrical testing methods,non-electrical passive testing methods,and non-electrical active testing methods.The paper offers a retrospective assessment of the applications of these methods in insulating polymers.Finally,evaluation of the applicability,advantages,and limitations of these diverse methods is systematically conducted,aiming to facilitate the targeted selection of the optimal NDT method in engineering applications.
基金This work was financially supported by the National Natural Science Foundation of China(No.52073207)the Fundamental Research Funds for the Central Universities.L.Y.also gratefully acknowledges the Open Fund of State Key Laboratory of Applied Optics(No.SKLAO2021001A17)and the Peiyang Scholar Program of Tianjin University.Fruitful discussion with Prof.Hang Yin is greatly appreciated.
文摘Insulating polymers(commodity plastics in particular)are a major category of polymeric materials widely used in our daily life,but they exhibit abysmal electrical conductivity.Instead,conjugated polymers are gaining tremendous interest due to their excellent electrical properties and versatile applications in organic electronics.In this perspective,we provide a concise account of the added value in organic solar cells,as brought by the combined use of conjugated and insulating polymers.The challenging tasks and prospective directions are given to the potential benefits of employing insulating polymer additives,which spans from common commodity plastics to high-temperature resistant resins and thermoplastic elastomers.Particularly,the inert polymers can improve many important properties such as mechanical and thermal robustness but not sacrifice optoelectronic performance.
基金supported by the National Key R&D Program(Grant No.2022YFA1203-100)sponsorship by Shanghai Sailing Program(Grant No.24YF2713800)+2 种基金financial support from the Local College Capacity Building Project of Shanghai Municipal Science and Technology Commission(Grant No.20010500700)the Natural Science Foundation of Shanghai(Grant No.23ZR1424300)Shanghai Shuguang Program(Grant No.22SG56)。
文摘In integrated circuit packaging,thermal interface materials(TIMs)must exhibit high thermal conductivity and electrical resistivity to prevent short circuits,enhance reliability,and ensure safety in high-voltage applications.We proposed the thermal-percolation electrical-resistive TIM incorporating binary fillers of both insulating and metallic nanowires with an orientation in the insulating polymer matrix.High thermal conductivity can be achieved through thermal percolation,while electrical non-conductivity is preserved by carefully controlling the electrical percolation threshold through metallic nanowire orientation.The electrical conductivity of the composite can be further regulated by adjusting the orientation and aspect ratio of the metallic fillers.A thermal conductivity of 10 W·m^(-1)·K^(-1)is achieved,with electrical non-conductive behavior preserved.This approach offers a pathway to realizing“thermal-percolation electrical-resistive”in hybrid TIMs,providing a strategic framework for designing high-performance TIMs.
基金supported by the Science and Technology Project of State Grid Corporation of China(Grant 5500-202455120A-1-1-ZN).
文摘The multifrequency voltage(MFV)stress,including switching impulses and harmonics,commonly appearing in the modern power system will stimulate the multifrequency impedance dynamics behaviours of electrical insulation.Therefore,this article presents a novel concept of insulation resilience response(IRR)by employing polymer insulation materials,which may be extended to electrical insulation resilience(EIR).The focus is on understanding reversible recovery performance and supporting physics-informed condition assessment for electrical insulation exposed to MFV.The underlying physical mechanisms and modelling methodologies are integrated to characterise the IRR behaviours of polymer insulation systems.The multifrequency dielectric/impedance properties of different resin dielectrics under diverse temperatures are comparatively investigated as proofofconcept cases.Furthermore,multidimensional sensitivity indicators are developed to quantify the electrical insulation resilience behaviour.A radar plot representation integrating resilience sensitivity indicators qualitatively assesses the IRR behaviours of polymer insulation systems.Additionally,a quantification methodology,including the resilience index(RI)and time-varied RI(TVRI),is proposed for the reversible recovery performance analysis for electrical insulation,respectively.Ultimately,an application-oriented framework derived from TVRI is provided to analyse the recovery performance evolution behaviours of electrical insulation under complex operating conditions.This offers a key theoretical foundation for insulation performance characterisation and condition analysis for high-voltage power equipment.
文摘Polymer insulating through-silicon-vias （TSVs） is an attractive approach for high-performance 3D integration systems. To further demonstrate the polymer insulating TSVs, this paper investigates the thermal stability by measuring the leakage current under bias-temperature condition, studies the thermal stress characteristics with Finite Element Analysis （FEA）, and tries to improve the thermal mechanical reliability of high-density TSVs array by optimizing the geometry parameters of pitch, liner and redistribution layer （RDL）. The electrical measurements show the polymer insulating TSVs can maintain good insulation capability （less than 2x 10TM A） under challenging bias-temperature conditions of 20 V and 200~C, despite the leakage degra- dation observation. The FEA results show that the thermal stress is significantly reduced at the sidewall, but highly concen- trates at the surface, which is the potential location of mechanical failure. And, the analysis results indicate that the polymer insulating TSVs （diameter of 10 μm, depth of 50 μm） array with a pitch of 20 μm, liner thickness of 1 μm and RDL radius of 9 μm has an optimized thermal-mechanical reliability for application.
基金supported by the National Natural Science Foundation of China(Nos.52073207,22075200,and 51703158)L.Y.expresses thanks for the start-up grant of Peiyang Scholar program from Tianjin University and the Open Fund of the State Key Laboratory of Luminesce nt Materials and Devices(South China University of Technology,No.2020-skllmd-11)+1 种基金M.L.thanks the Peiyang Young Junior Faculty Program of Tianjin University(No.2019XRG-0021)L.Y.acknowledges the merit beamtime(Project ID:15692)approved by the Australian Synchrotron and beamtime(Project ID:2020-BEPC-PT-004082)approved by Beijing Synchro-tron Radiati on Facility.
文摘Record-breaking organic solar cells(OSCs)based on blends of polymer donors and small molecule acceptors often show undesirable degradati on,which severely precludes their practical use.Herei n,we demonstrate a facile and cost-effective approach to con struct thermally stable OSCs at 150℃ by incorporating a small amount of a polymer insulator polyacenaphthylene(PAC)with high glass-transition temperature over 230℃ into polymer:acceptor blends.The model PTB7-Th:EH-IDTBR blend with 10 wt%PAC maintained above 85%of its initial efficiency upon continuous heating at 150℃ for over 800 h,while the efficiency of the blend without PAC sharply dropped by 70%after-300 h.Owing to high miscibility with acceptors,PAC confines the motion of the acceptor molecules and suppresses the acceptor crystallization at elevated temperatures,leading to significantly improved stability.Importantly,the effectiveness of this blending approach was also validated in many other OSC systems,showing great potential for achieving high-performance thermally stable electronics.
