通过溶液静电纺丝法制备了聚芳醚砜酮(PPESK)微纳米纤维膜,借助于扫描电子显微镜和拉伸试验机分别对纤维膜的形貌和力学性能进行了表征,用正交试验对微纳米纤维膜的制备工艺参数进行了优化。结果表明,在给定条件下,对纤维直径影响由大...通过溶液静电纺丝法制备了聚芳醚砜酮(PPESK)微纳米纤维膜,借助于扫描电子显微镜和拉伸试验机分别对纤维膜的形貌和力学性能进行了表征,用正交试验对微纳米纤维膜的制备工艺参数进行了优化。结果表明,在给定条件下,对纤维直径影响由大到小的工艺参数依次为:溶液浓度>给料速度>纺丝电压。纤维直径最小的工艺条件为:溶液浓度19%,纺丝电压10 k V,给料速度为0.04 mm/min。对纤维膜拉伸强度影响由大到小的工艺参数依次为:给料速度>纺丝电压>溶液浓度。纤维拉伸强度最大的工艺条件为:溶液浓度24%,纺丝电压14 k V,给料速度0.04 mm/min。展开更多
Poly(phthalazinone ether sulfone ketone)(PPESK)is a new-generation high-performance thermoplastic resin that exhibits excellent thermal stability and mechanical properties.However,its damage and failure mechanisms und...Poly(phthalazinone ether sulfone ketone)(PPESK)is a new-generation high-performance thermoplastic resin that exhibits excellent thermal stability and mechanical properties.However,its damage and failure mechanisms under high-temperature and high-strain-rate coupling conditions remain unclear,significantly limiting the engineering applications of PPESK-based composites in extreme environments such as aerospace.To address this issue,in this study,a temperature-controlled split Hopkinson pressure bar experimental platform was developed for dynamic tensile/compressive loading scenarios.Combined with scanning electron microscopy and molecular dynamics simulations,the thermomechanical behavior and failure mechanisms of PPESK were systematically investigated over the temperature range of 293-473 K.The study revealed a novel"dynamic hysteresis brittle behavior"and its underlying"segmental activation±response lag antagonistic mechanism".The results showed that the strain-rate-induced response lag of polymer chain segments significantly weakened the viscous dissipation capacity activated by thermal energy at elevated temperatures.Although high-strain-rate conditions led to notable enhancement in the dynamic strength of the material(with an increase of 8%-233%,reaching 130%-330%at elevated temperatures),the fracture surface morphology tended to become smoother,and brittle fracture characteristics became more pronounced.Based on these findings,a temperature±strain rate hysteresis antagonistic function was constructed,which effectively captured the competitive relationship between temperature-driven relaxation behavior and strain-rateinduced hysteresis in thermoplastic resins.A multiscale damage evolution constitutive model with temperature±rate coupling was subsequently established and numerically implemented via the VUMAT user subroutine.This study not only unveils the nonlinear damage mechanisms of PPESK under combined service temperatures and dynamic/static loading conditions,but also provides a strong theoretical foundation and engineering guidance for the constitutive modeling and parametric design of thermoplastic resin-based materials.展开更多
文摘通过溶液静电纺丝法制备了聚芳醚砜酮(PPESK)微纳米纤维膜,借助于扫描电子显微镜和拉伸试验机分别对纤维膜的形貌和力学性能进行了表征,用正交试验对微纳米纤维膜的制备工艺参数进行了优化。结果表明,在给定条件下,对纤维直径影响由大到小的工艺参数依次为:溶液浓度>给料速度>纺丝电压。纤维直径最小的工艺条件为:溶液浓度19%,纺丝电压10 k V,给料速度为0.04 mm/min。对纤维膜拉伸强度影响由大到小的工艺参数依次为:给料速度>纺丝电压>溶液浓度。纤维拉伸强度最大的工艺条件为:溶液浓度24%,纺丝电压14 k V,给料速度0.04 mm/min。
基金supported by National Key Research and Development Program"Advanced Structures and Composite Materials"Special Project[Grant No.2024YFB3712800]the Fundamental Research Funds for the Central Universities[Grant No.DUT22-LAB605]Liaoning Province's"Unveiling the List and Leading the Way"Science and Technology Research and Development Special Project[Grant No.2022JH1/10400043]。
文摘Poly(phthalazinone ether sulfone ketone)(PPESK)is a new-generation high-performance thermoplastic resin that exhibits excellent thermal stability and mechanical properties.However,its damage and failure mechanisms under high-temperature and high-strain-rate coupling conditions remain unclear,significantly limiting the engineering applications of PPESK-based composites in extreme environments such as aerospace.To address this issue,in this study,a temperature-controlled split Hopkinson pressure bar experimental platform was developed for dynamic tensile/compressive loading scenarios.Combined with scanning electron microscopy and molecular dynamics simulations,the thermomechanical behavior and failure mechanisms of PPESK were systematically investigated over the temperature range of 293-473 K.The study revealed a novel"dynamic hysteresis brittle behavior"and its underlying"segmental activation±response lag antagonistic mechanism".The results showed that the strain-rate-induced response lag of polymer chain segments significantly weakened the viscous dissipation capacity activated by thermal energy at elevated temperatures.Although high-strain-rate conditions led to notable enhancement in the dynamic strength of the material(with an increase of 8%-233%,reaching 130%-330%at elevated temperatures),the fracture surface morphology tended to become smoother,and brittle fracture characteristics became more pronounced.Based on these findings,a temperature±strain rate hysteresis antagonistic function was constructed,which effectively captured the competitive relationship between temperature-driven relaxation behavior and strain-rateinduced hysteresis in thermoplastic resins.A multiscale damage evolution constitutive model with temperature±rate coupling was subsequently established and numerically implemented via the VUMAT user subroutine.This study not only unveils the nonlinear damage mechanisms of PPESK under combined service temperatures and dynamic/static loading conditions,but also provides a strong theoretical foundation and engineering guidance for the constitutive modeling and parametric design of thermoplastic resin-based materials.
