Synthesis And Characterization Of Jacketed Polymers With Different Main Chains And Side Chains

Side-chain liquid crystalline polymers(SCLCPs)constitute an important class of materials that represents new advanced organic functional materials combining both anisotropic order of liquid crystals and comprehensive properties of polymers.SCLCPs are usually designed and synthesized based on the innovative “spacer decoupling principle” suggested by Finkelmann.It usually comprises several structures: the polymer backbone,the spacer and the mesogen units.The insertion of spacers with reasonable lengths between the backbone and mesogens can effectively decouple dynamics of backbone and mesogen,and thus facilitate ordered packing of side-chains.In this dissertation,a series of jacketed polymers with different mesogen side chains and main chains,mainly focuses on the physical performance of polymers were preliminary studied.The main research works of this paper are as follows:1.According to the previous formation of poly-{2,5-bis[(4-butoxyphenyl)oxycarbonyl] styrene}(PBPCS)fiber was studied,this material exhibit properties that PBPCS fiber is a kind of novel temperature response shape memory material in molecular level.A series of jacketed polymers with different mesogens and length of terminal groups were designed and synthesized,the names of poly-{2,5-di(4’-alkoxybenzene)vinyltherephthalate}(PnCPCS,n is the number of carbons in the alkoxy groups,n=1,4,10,16)and poly-{2,5-di(4’-alkoxydibenzene)vinyltherephthalate}(PnbiPCS,n is the number of carbons in the alkoxy groups,n=0,4,10,16),which is based on PBPCS fiber.The yield of intermediates was improved in the progress of synthetic polymers.The chemical structures of the monomers and polymers were confirmed by ~1H NMR.The results showed that all the polymers had good thermal stability by thermogravimetric analysis(TGA)and got a relatively high glass transition temperature by differential scanning calorimetry(DSC).2.A novel series of SCLCPs with the structure of 2-ethenylbenzoic acid as rigid core were designed and synthesized,the names of poly-{2-vinylbenzoic acid(4’-alkoxyphenyl/biphenyl/terphenyl)esters} [PVB(Ph/biPh/terPh)-Cn,n is the number of carbons in the alkoxy groups,n=4,10],which belong to the kind of laterally attached SCLCP.The chemical structures of the monomers and polymers were confirmed by ~1H NMR.The inflence of the asymmetry of mesogen and different numbers of benzene on SCLCPs physical properties was discussed.Especially,the terphenyl group is introduced to enhance the rigid of mesogen.The results showed that the thermal stability of polymers were higher by TGA.The polymers of PVBterPh-C4 and PVBterPh-C10 have got a higher significantly glass transition temperature when it’s compared to another polymers by DSC.3.A series of rod-coil block copolymers containing crystallizable poly(ε-caprolactone)and the jacketed polymers of PBPCS,PbiPCS,PVBPh-C4 and PVBbiPh-C4 were designed and synthesized by ring-opening polymerization of ε-caprolactone and subsequent atom transfer radical polymerization(ATRP).The chemical structures of the monomers and polymers were confirmed by ~1H NMR.The whole polymer chain is destroyed,due to the addition of the flexible segment decrease intermolecular packing arrangments.Therefore,it was decreased thermal stability by TGA.The existence of microphase separation was identified by DSC.4.Two kinds of mesogen-jacketed conjugated polymers polythiophenes(P1 and P2)were successfully designed and synthesized by Stille coupling reaction,which containing terphenyl mesogenic side chain with electron donor group and elctron withdrawing group.The chemical structures of the monomers and polymers were confirmed by ~1H NMR.All the polymers have good thermal stability,losing 5% weights was found when it’s heated to 316℃ and 262℃ respectively.P1 and P2 got a relatively low glass transition temperature of 54℃ and 16.6℃ separately.The polymers with donor-acceptor units UV-vis light absorption are more strongly than those without such push-pull pairs,and the UV-vis light absorption rang is 425 nm-650 nm.The band gap of P1 and P2 are 1.90 eV by calculation.And we found P1 and P2 have a potential application for polymer solar cell’s donor materials.