Polynaphthalimide(PNI)with six-membered imide ring(_(6-)PI)has better chemical resistance than five-membered imide ring(_(5-)PI),but is difficult to be processed into nano fibers due to the poor processability.In this...Polynaphthalimide(PNI)with six-membered imide ring(_(6-)PI)has better chemical resistance than five-membered imide ring(_(5-)PI),but is difficult to be processed into nano fibers due to the poor processability.In this work,we proposed a template strategy to fabricate nanofiber _(6-)PI membranes and their composite membranes.Neat _(6-)PI and _(6-)PI composite fibrous membranes were prepared using high-molecular-weight polymers _(5-)PAA and PVP as templates by electrospinning.FTIR,DMA,TGA and tensile tests were used to characterize their chemical structures,thermal stability and mechanical properties.Further eye-observation,micro-morphology investigation and tensile tests were applied to evaluate the chemical resistance of nanofibrous membranes in strong acid,strong alkaline,and concentrated salt.The results demonstrated that 6-PI nano fibrous membra nes possessed the best thermal stability,best acid,alkaline,and salt resista nee with the highest mecha nical rete ntion.This study will provide basic information for high-performance electrospun 6-PI nanofiber membranes and provide opportunities for applications of Pls in different chemically harsh environments.展开更多
基金by the National Natural Science Foundation of China(Nos.21975111,21774053,and 51803093)Natural Science Foundation of Jiangsu Province(No.BK20180770)and Open Project of Chemistry Department of Qin gdao Un iversity of Scie nee and Technology(No.QUSTHX201921).
文摘Polynaphthalimide(PNI)with six-membered imide ring(_(6-)PI)has better chemical resistance than five-membered imide ring(_(5-)PI),but is difficult to be processed into nano fibers due to the poor processability.In this work,we proposed a template strategy to fabricate nanofiber _(6-)PI membranes and their composite membranes.Neat _(6-)PI and _(6-)PI composite fibrous membranes were prepared using high-molecular-weight polymers _(5-)PAA and PVP as templates by electrospinning.FTIR,DMA,TGA and tensile tests were used to characterize their chemical structures,thermal stability and mechanical properties.Further eye-observation,micro-morphology investigation and tensile tests were applied to evaluate the chemical resistance of nanofibrous membranes in strong acid,strong alkaline,and concentrated salt.The results demonstrated that 6-PI nano fibrous membra nes possessed the best thermal stability,best acid,alkaline,and salt resista nee with the highest mecha nical rete ntion.This study will provide basic information for high-performance electrospun 6-PI nanofiber membranes and provide opportunities for applications of Pls in different chemically harsh environments.