Synthesis Of Perylenediimide (PDI)-Contained Pendent Polymer Based On ROMP Reaction And Their Electronic Memory Characteristics

Due to the advantages of good scalability,low cost,good flexibility,and good processability compared with conventional silicon-based devices,organic materials have recently attracted widespread attention in the field of resistive memory devices.Therefore,scientists from all over the word have tried to do some efforts related to organic materials.So far,organic small molecules containing carbazole,Perylenediimide functional groups have been designed and synthesized,showing different types of storage performance.However,the research of materials is still in its infancy,and the photoelectric properties of the materials still need to be optimizedto improve the device performance.Due to its advantages of easy processing,low power consumption,rich in structure,and high density,polymer can potentially be used for future information storage.Thus,the side chain polymers and block polymers were synthesized based on functional groups such as carbazole,Perylenediimide and their electrical storage properties were studied.We did the following parts:(1)The functional polymers have been widely applied in the research of memory device due to several advantages as large scalability,good flexibility,and excellent processability.Herein,a novel non-conjugated polymer with perylenediimide(PDI)pendent was successfully synthesized through the newly ring-opening metathesis polymerization(ROMP).Through tuning the ratio of 1,2-dichlorobenzene(o-DCB)and methanol(Me OH)solvents,the polymer showed different surface morphologies and polymeric crystallinity in film state.The sandwich structured device ITO/polymer/Al exhibited different electric behaviors,and the threshold voltages of the devices were also affected with different mixed solvent ratios.This study suggests that the polymeric memory behavior could be efficiently adjusted through mixed solvents,which are of great significance for future research.(2)Based on PPDI,the carbazole group was introduced by ROMP polymerization and two different ratio block copolymers PPDI1-b-CZ1,PPDI1-b-CZ5(based on Perylenediimide-carbazole group)were designed and synthesized.In both polymers,there is not only the interaction between the perylenediimide(electron-withdrawing group)and the carbazole donor group(D-A),but also the space between the functional group and the main chain through the flexible chain,so that under the electric field,the side chain groups can be conformationally transformed.Thus,the polymer device exhibits ternary storage performance under the dual mechanism.The device(ITO/PPDI1-b-CZ5/Al)storage performance is superior to that of ITO/PPDI1-b-CZ1/Al.This is due to the fact that the introduction of carbazole with good solubility will improve the film quality of the polymer.(3)The performance of organic memory devices is related to the accumulation of active layers,film quality,and thickness.In order to obtain films with good stacking,higher film quality and uniform thickness,(actually,good stacking and uniform thickness are belong to the high film quality),more processes are demanding for the film technology.Therefore,the construction of molecular devices based on various types of molecular self-assembly have received more and more attention and the use of amphiphilic polymers to prepare nanoparticle devices is one of the most effective methods.In this paper,we synthesized a triblock amphiphilic copolymer(PDI-CZ-PEG)by the ROMP method.Due to the introduction of the hydrophilic chain PEG,we can finally assemble nanoparticles by dialysis.Finally,we tested the electrical storage properties of the micelle particles through a conductive atomic force microscope(c-AFM).The experimental results show that the micelle particles have storage properties.The use of c-AFM probes enables micro-nano devices to be read and written in the near future.In turn,the device memory capacity can be increased through preparing micro-nano size memory cells.According to the above research,the polymeric memory behavior could be efficiently adjusted through mixed solvents,which are of great significance for future research.Based on PPDI,the carbazole group was introduced by ROMP polymerization and diblock copolymers PPDI-b-CZ(based on Perylenediimide-carbazole group)were designed and synthesized.The device behavior exhibits ternary WORM storage behavior.Due to the introduction of the hydrophilic chain PEG,we can finally assemble some nanoparticles and we have successfully performed a research on the storage performance of nanospheres,which pave the way for the application of organic electricity storage.