Preparation And Properties Of Polyester/Amide Polymers Containing Tetrastyrene Units

As two sets of typical engineering plastics,polycarbonate(PC)and polyamide(PA)display the advantages of simple preparation,excellent comprehensive performance,and have been widely applied in industrial fields.The current researches of PC and PA are focused on the modification of their mechanics,thermology,electrical-resistance and blend with other materials.However,the photoelectronic properties of PC and PA have rarely been reported so far,and the related research will play a positive role in expanding the application field of such polymers.Tetraphenylethylene(TPE)is a type of photoelectronic functional molecule,which with specific aggregated fluorescence enhancement effect(AIEE).TPE possesses some characteristics,such as simple preparation,easy to be modified by other functional groups and with three-dimensional molecular configuration.As a result,it has been widely used in various research fields such as optoelectronics,sensing and biology.In this thesis,TPE is selected as the active framework,and phenolic hydroxyl(-OH)and isocyano(-NC)functional groups were introduced into its structure as polymerization sites.Direct Polymerization and postpolymerization protocols were used to realize the preparation of PC and PA-derivatives with special photoelectric characteristics.Optical,catalytic and electrochemical properties of obtained polymers were studied here from the following aspects:1.The dihydroxy-substituted TPE derivative(M1)was synthesized firstly,and the corresponding TPE-containing PC(PC-2)was successfully prepared by using M1/bisphenol A(BPA)as combined phenol sources via homogeneous polycondensation with triphosgene in dichloromethane.The AIEE characteristic of PC-2 was demonstrated by studying fluorescence emission in a mixed solvent system of THF(good solvent)/water(poor solvent).Subsequent investigation showed that PC-2 exhibited significant fluorescence quenching response to nitro compounds[2,4-dinitrophenol(DNP)and picric acid(PA)]in THF-water(VTHF/VWater=1/99)co-solvent system;2.A series of TPE-decorated,functional PA were successfully prepared with isocyanodecorated TPE derivative(M3 and M4)and main-chain type benzoxazine precursor(P1)as starting compounds via efficient benzoxazine-isocyanide chemistry(BIC)under mild conditions.The representative polymer,P2-2,exhibits typical AIEE characteristic,and was applied as fluorescence probe to detect nitro compounds in high-water fraction medium(fw%=90%).In addition,the residual isocyano(-NC)groups on obtained polymer(P2-3)were utilized to bind with CuCl,and the resulting polymer/metal complex(P2-3-CuCl)can be applied as efficient heterogeneous catalyst for azide-alkyne cycloaddition reaction in air;3.A type of TPE-based crosslinked polybenzoxazine(P4)was successfully constructed,and corresponding cross-linked PA(P5)was prepared via solid-phase BIC reaction by using P4 and 4,4'-diisocyanobiphenyl(M6)as raw materials.Subsequently,the application of P5 in the electrochemical detection of bisphenol A(BPA)was preliminarily studied.