Synthesis of Telechelic and Three-Arm Polytetrahydrofuran-block-amylose

Telechelic amine terminated polytetrahydrofuran (PTHF) is prepared via cationic ring opening polymerization (CROP) of THF, initiated by trifluoromethanesulphonic anhydride (triflic anhydride). Hexamethylene tetramine (HMTA) is used as a terminating agent. The resulting HMTA terminated PTHF is hydrolyzed to result in an amine terminated PTHF. Reductive amination is carried out by reacting the PTHF with maltoheptaose resulting in maltoheptaose-b-PTHF-b-maltoheptaose. The product is prepared as a primer for the enzymatic polymerization to synthesize amylose-b-PTHF-b-amylose. In addition, a three-arm PTHF is prepared via CROP of THF. The initiator is synthesized in situ by the reaction of triflic anhydride and triethanol amine. The resulting amine terminated three-arm PTHF is reacted with maltoheptaose to synthesize a three-arm PTHF-b-maltoheptaose which can be used for the enzymatic synthesis of three-arm PTHF-b-amylose. Characterization of the products is difficult due to the amphiphilic behavior of both telechelic amylose-b-PTHF-b-amylose and three-arm PTHF-b-amylose. Therefore, the analysis of the products is mainly based on attenuated total reflectance Fourier transform infrared spectroscopy.