Amphiphilic hyperbranched polymers:synthesis,characterization and self-assembly performance

A series of amphiphilic hyperbranched polymers(AHP-s,the "s" refers to the algebra of AHP) were synthesized by the reaction between hydroxyl-terminated hyperbranched polymers(HBP-s,the "s" refers to the algebra of HBP)and palmitoyl chloride.FTIR,NMR and GPC were used to determine the structure of AHP-s,the results showed that AHP-s exhibits core-shell structure.The thermal properties of polymers were investigated by DSC and TGA.It was found that AHP-2,AHP-3 and AHP-4 display higher thermal stability than AHP-1(AHP-1,AHP-2,AHP-3 and AHP-4represent the first,second,third and fourth generation AHP,respectively).Furthermore,the self-assembly performance of AHP-s in THF solvent was investigated by TEM and SEM.Finally,the encapsulation capacity of the AHP-s for methyl orange(MO) was explored at different concentrations of AHP-s and pH conditions.It was found that AHP-s is capable of accommodating hydrophilic guest MO.Moreover,the higher generation of AHP-s,the stronger encapsulation capacity obtained.And the encapsulation capacity closely associated with the pH of encapsulation system.