Synthesis And Properties Of Novel Aromatic Polyamides And Poly (Aryl Ether Ketone)s Containing Pendant 4-benzoyl-2,3,5,6-tetrafluorophenoxy Groups

This dissertation introduces the recent research progress of aromatic polyamides and poly(aryl ether ketone)s.We designed and prepared a novel di-aroyl chloride monomer–5-(4-benzoyl-2,3,5,6-tetrafluorophenoxy)isophthaloyl dichloride.A series of novel aromatic polyamides and poly(aryl ether ketone)s containing pendant4-benzoyl-2,3,5,6-tetrafluorophenoxy groups were synthesized by polycondensation of this new di-aroyl chloride monomer with six kinds of aromatic diamine monomers and five kinds of aromatic ether monomers,respectively.The introduction of flexible pendant 4-benzoyl-2,3,5,6-tetrafluorophenoxy groups into the polymer molecular chain resulted in the increase in the distance between the polymer molecular chains and increase in the free volume,so that the polymer can be better dissolved in organic solvents,improving processability.1.A series of novel aromatic polyamides containing pendant 4-benzoyl-2,3,5,6-tetrafluorophenoxy groups were synthesized by low temperature solution polycondensation of 5-(4-benzoyl-2,3,5,6-tetrafluorophenoxy)isophthaloyl dichloride with pphenylenediamine,2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane,3,4'-oxydianiline,4,4'-oxybisbenzenamine,2,2'-bis(trifluoromethyl)benzidine,and 1,5-naphthalenediamine,respectively.The obtained polyamides were characterized by FT-IR,NMR,DSC,TGA so on.The glass transition temperatures of this series of polymers were in the range of 212-243 oC,the inherent viscosities were above 0.66dL/g,the transmittances of the polymers at 500 nm were more than 94%,the decomposition temperatures at 10% weight loss were above 400 oC.All the polymers were soluble in strong polar solvent such as DMAc,NMP,DMSO and DMF at room temperature.The results showed that,the introduction of flexible pendant4-benzoyl-2,3,5,6-tetrafluorophenoxy groups could decrease the regularity of polymer chains,diminish the interaction of macromolecular chains,and increase the free volumes,significantly improving aramid solubility and processability.2.A series of novel poly(aryl ether ketone)s containing pendant 4-benzoyl-2,3,5,6-tetrafluorophenoxy groups were synthesized by electrophilic Friedel-Crafts solutionpolycondensation of 5-(4-benzoyl-2,3,5,6-tetrafluorophenoxy)isophthaloyl dichloride with oxydibenzene,naphthalene-1,4-diylbis((4-phenoxyphenyl)methanone),4,4'-sulfonylbis(phenoxybenzene),1,1'-((sulfonylbis(4,1-phenylene))bis(oxy))dinaphthalene,and 1,3-phenylenebis((4-phenoxyphenyl)methanone),respectively.The obtained polymers were characterized by FT-IR,NMR,DSC,TGA so on.The inherent viscosities of the polymers are over 0.5 dL/g,the glass transition temperatures of this series of polymers were in the range of 216-242 oC,the transmittances of the polymers at 400 nm were more than 80%.The decomposition temperatures at 10%weight loss were above 400 oC.All the polymers were soluble in strong polar solvent such as DMAc,NMP,DMSO,DMF at room temperature.The results showed that,the poly(aryl ether ketone)s containing pendant 4-benzoyl-2,3,5,6-tetrafluorophenoxy groups exhibited good thermal stability and high optical transparency.The introduction of flexible pendant 4-benzoyl-2,3,5,6-tetrafluorophenoxy groups into poly(aryl ether ketone)macromolecular chains resulted in the increase in the distance between the molecular chains,the increase in free volumes,significantly improving aramid solubility and processability.