Novel Sulfur(?) Fluoride Exchange Based Click Synthesis Of Ct Structure Based Polysulfates And Their Switchable Electrical Bi-stable State Performance

According to Moore's Law,the storage capacity of inorganic semi-conductor based memory materials has reached physical and theoretical limits.Recently,polymer based memory materials have been one of the most promising alternatives for high-density storage,as they have advantages of low turn-on voltage,high storage capacity,rich designable structures,good film processing performance,flexibility,high mechanical strength,prefect calability and so on.In general,organic polymers are synthesized by the polycondensation reactions which need anhydrous,anaerobic and hyperthermal conditions.Compared with other polycondensations,the SO₂F transesterification polymerization can occur in more moderate reaction conditions and have faster reaction rate,higher reaction conversion,higher molecular weights of the polymers as well as more controllable molecular weights.Polysulfates synthesized by this new method have distinct advantages,including superior thermal stability,strong abilities to resist hydrolysis and oxidation reduction,corrosion resistance,rich designable structures and easy film processing.In addition,the electron density of the sulfate group is high,making the polysulfates suitable for electric transport and become potential electrical storage materials.In this paper,the main chain homopolymers,main chain copolymers and main chain copolymers with different transfer properties have been designed and synthesized by SO₂F transesterification polymerization.The storage properties of the storage material are adjusted and optimized by polymerization,addition of electron donating,electron withdrawing groups for feeding and different spatial flatness.?1?PolyTPP-NI including naphthalimide-pyrazoline groups was synthesized by SO₂F transesterification polymerization method with MTPP-NI acting as the precursor.Structures with large conjugated systems can be applied in polysulfates.In the same unit,the introduction of the sulfate bond resulted in different storage properties of the small molecule MTPP-NI and the polymer PolyTPP-NI storage devices.The small molecule memory device exhibits DRAM performance while polymer memory device exhibits FLASH performance.This work uses the charge transfer between naphthalimide-pyrazoline groups and the different planarities of precursors and polymers to study the storage properties of memory devices.?2?The copolymers of CoTPP-NIS with A-D-b-A structure and CoTPP-NIN with A-D-b-D structure are synthesized by copolymerizing a monomer containing an electron withdrawing group or an electron donating group and a monomer containing a naphthalimide-pyrazoline group by SO₂F transesterification polymerization.Both memory devices show FLASH performance and the A-D-b-D structural material storage device possesses lower turn-on voltage.The charge transfer between A-D-b-A structure and A-D-b-D structure can be used to explain the storage performance of the storage device?3?Two kinds of sulfuric acid ester copolymers PBPN and PFPN with different molecular planes were designed and synthesized by SO₂F transesterification polymerization of the monomers containing electron withdrawing group with different planarities and the monomer containing an electron donating group.By changing the planarity of the molecule to affect the charge transfer,the electrical storage performance of the memory device can be influenced.Two-step polycondensation method was used to synthesize polyimide PPh and PNa with different degree of conjugation.From the molecular plane,we studied the effect on polymer storage properties.The performance of the memory device is changed by changing the degree of molecular conjugation.ITO/PBPN/Al device and ITO/PFPN/Al device both exhibit stable nonvolatile WORM electrical storage behavior.Due to the flatness of the molecules,the PFPN device has a lower turn-on voltage.The ITO/PPh/Al device exhibited a typical non-volatile WORM memory characteristic.The ITO/PNa/Al device exhibited a non-volatile flash memory characteristic.From the foregoing we can know that compared with the precursors,the storage performance of the sulfide bond-based polymers synthesized by SO₂F transesterification polymerization can be affected by the copolymerization and the change of molecular planicity.The study can provide new ideas for the design of storage materials.