Synthesis And Characterization Of Polyurethane With Pendant Amino Group

Due to its reliable compatibility, bioresorbability and mechanical properties, aliphatic polyester is an important biomedical material which can be used as biodegradable sutures, drug delivery, tissue engineering scaffold and so on. However, its insufficient hydrophilic and high crystallinity undermine its controllable degradation and cell compatibility. What is more, molecular chain of aliphatic polyester has not any functional or active pendant group. So preparation of a novel polyester with pendant groups like amino group, hydroxyl group and carboxyl group becomes very important. In this article, there are a series of functional polyurethane have been synthesized and characterized.First, several kinds of PCL-diols with pendant groups were synthesized through ring-opening polymerization (ROP) of s-caprolactone (CL) and y-(carbamic acid benzyl ester)-s-caprolactone (CABCL) using Sn(Oct)? as catalyst and glycol as initiator. They were characterized by 1H NMR and FT-IR and it shows that the structure and components of PCL-diols were the same as expected. Then a series of PUs were prepared by reaction of IPDI, PCL-diols as soft segment and 1,4-BDO as extender. The properties of PUs were compared and analyzed through changing the value of r, which is equal to n(IPDI)/n(PCL-diol). and PCL-diol used in polymerization. The structure and properties, such as crystallinity, hydrophilicity and mechanical properties, of PUs were characterized with FT-IR.’H NMR. XRD. contact angle machine and mechanical testing machine. It indicates that the introduction of carbamic acid benzyl ester group lowered its crystallinity effectively and improved the flexibility of PUs greatly.Afterwards.the PUs involved above were processed through deprotection which made the samples obtain lots of pendant amino groups. Because these pendant groups can react with some related chemically or biologically active reactant. PUs with amino group have lots of potential application in controlled delivery of drug.surgery and tissue engineering. Besides. the results of characterization show that the growth of content of amino group in PUs improved their hydrophilicity tremendously.