Synthesis Of New Organic Bisphenol Monomers, Poly (Aryl Ether)s And Properties Of The Polymers

In recent years aromatic polyether ketones and polyether sulfones have achieved remarkable positions among other thermoplastic polymers because of their unique combination of toughness,stiffness,thermooxidative stability,electrical performance, flame retardancy and retention of physical properties at high temperatures.So they have been successfully applied in many fields such as aviation,spaceflight,nuclear energy,communication,telecom,petroleum,as well as machine manufacturing and traffic.At the same time,this kind of polymer,usually processed at high temperature was considered as a disadvantage for processing.So a great deal of research has been made on the introduction of pendent groups onto poly(aryl ether ketone)s and poly(aryl ether sulfone)s,the introduction of fluorine substitution and bulky side groups are regarded as effective ways to improve the solubility,increase the thermal stability,reduce the moisture absorption and dielectric constant.The aim of this dissertation was concentrated on synthesis of new monomers containing pendent group and fluoropolymers.new Fluoropoly(aryl ether ketone)s(FPAEK)and Fluoropoly(aryl ether sulfone)s(FPAEF)were prepared based on synthesized monomers.Firstly two new bisphenol monomers,(4-fluoro)phenylhydroquinone and (3,4-difluoro)phenylhydroquinone,were synthesized from fluorine-contained aniline,1,4-benzoquinone,and other raw materials through three-step reactions:Azo, substitution,reduction.It was demonstrated that the structures of monomers were in agreement with the designed composition by H¹-NMR,FT-IR,MS,and the products had high purity.Fluoropoly(aryl ether ketone)s(FPAEK)and Fluoropoly(aryl ether sulfone)s (FPAEF)were prepared from the three bisphenol monomers[2-phenyhydroquinone, (4-fluoro)phenylhydroquinone and(3,4-difluoro)phenylhydroquinone)]and 4,4'-diflourodiphenylketone or bis-(4-chlorophenyl) sulfone via a nucelophilic aromatic substitution polycondensation,respectively.The structures of the polymers were investigated by ¹H-NMR and FT-IR,and the properties of FPAEK and FPAEF were also studied by DSC,TGA,WXRD,etc.It was found FPAEK and FPAEF show high temperature stability,i.e.the 5%weight loss temperatures were above 527℃and 507℃in N₂,and their glass transition temperatures(Tg)ranged from 150℃to 159℃for FPAEK and from 177℃to 196℃for FPAEF in N₂.Furthermore,these polymers have good solubility in some polar aprotic solvents such as NMP.DMAc, CHCl₃,etc,A series of copolymers were prepared from the bisphenol monomer together with resorcinol and 4,4'-diflourodiphenylketone via a nucelophilic aromatic substitution polycondensation.The structures of the copolymers were confirmed by ¹H-NMR and FT-IR,and the properties of these copolymers were studied by DSC,TGA,WXRD, etc.It was revealed that these copolymers possess high temperature stability,i.e.the 5%weight loss temperatures was above 510℃,and their glass transition temperatures (Tg)ranged from 123℃to 159℃.These copolymers also have good solubility in some polar aprotic solvents such as NMP,DMAc,CHCl₃,etc,which is an important advantage to process them for practical applications.Several copoly(aryl ether sulfone)s were obtained from the bisphenol monomer (4-fluoro)phenylhydroquinone together with resorcinol and bis-(4-chlorophenyl) sulfone via a nucelophilic aromatic substitution polycondensation.The structures of copolymers were confirmed by FT-IR,and the properties of these copolymers were also studied by DSC,TGA,WXRD,etc.It was found these copolymers show high temperature stability,i.e.the 5%weight loss temperatures were above 530℃in N₂, and their glass transition temperatures(Tg) ranged from 167℃to 196℃in N₂. Furthermore these copolymers have good solubility in NMP,DMF,DMSO,CH₂Cl₂, THF,CHCl₃,etc,which is an important advantage to process them for practical applications.