A Simple and Reusable Polyaniline Catalyst for the Ring-opening Polymerization of Tetrahydrofuran

Background: Polyaniline salts like polyaniline-sulfate (PANI-H2SO4), polyanilinehydrochloride (PANI-HCl), and polyaniline-phosphate (PANI-H3PO4) are swimmingly revealed as heterogeneous polymer supported catalysts for the polymerization of tetrahydrofuran to produce polytetramethylene ether glycol (PTMG). Method: Polymerization of tetrahydrofuran by ring-opening in acetic anhydride environment using the pint-sized PANI catalyst at room temperature for 2 h resulted in the product, PTMG in the order: PANI-H2SO4 (35%) > PANI-HCl (30%) > PANI-H3PO4 (20%). The molecular weight of PTMG synthesized by PANI-H2SO4, PANI-HCl and PANI-H3PO4 catalysts are found to be 2244, 2034 and 2019 respectively. Conclusion: These catalysts could be easily handled and reused. This approach gives phylloclade stem leaf-like morphology of highly crystalline polymer. Privileges of this method are reuasble, cheaper, user friendly synthesis, and eco-friendly nature of the catalyst.