Study On Preparation And Application Of Carboxylic Polystyrene

Polymer as reagent has been developed to be an important task in the field of organic synthesis and functional polymer chemistry by studying polymer support reaction. Polystyrene as a support has been applied in a wide domain, in this paper, carboxylic group is connected on the polystyrene and DVB copolymer (PS), monodisperse microspheres, and this carboxylic PS can be used in ion exchange, enzyme immobilization and PET drug synthesis.In the first part, advantage, preparation method and application of polymer reagent, characteristic, principle, classification and application of polymer support are summarized.In the second part, a new functionalized polystyrene-based(PS)resin is synthesized using phthalic anhydride (PA) as acetylation reagent by Friedel-Crafts Acetylation. This preparation method is simple, and carboxylic group is mainly distributed on the surface of PS other than some carboxylic resins are prepared by functionalized monomer. This reaction conditions is optimized (including reaction time, temperature etc.) and effect of nitrobenzene is discussed deeply. The loading of carboxylic PS is controlled in the range of 0～2.88mmol/g according to amount of PA. In the last part, the product of the second part is used in the following three aspects. Firstly the carboxylic polystyrene is affirmed as a kind of weak acid cation exchange resin through mensurated ion-exchange capacity and pH metric titration curve, and high carboxylic loading resin has high ion-exchange capacity. Secondly it is used as a support of PET medicine(thymidine,dT) and optimizes this reaction conditions. In this optimum reaction conditions, the carboxyl could be completely esterified by dT and dT could be completely looped. Meanwhile, another carboxylic PS is prepared by oxidized acetylation PS, reaction condition is primarily studied and using incontinuous reaction temperature based on incontinuous reaction mechanism. This resin is also applied in PET drug (dT) support Finally, based on the "Flexible immobilized enzyme" model, using this resin as immobilization support, it is found that recovery of immobilized papain by PS-COO-DAS is twice equal to recovery of immobilized papain by PS-NH-GA.