Synthesis and characterization of new calixarene-chitosan polymers

ABSTRACT

Triflate Ester of Calix[n]arene (n = 4, 6, 8) (TEC[n] (n = 4, 6, 8)) were synthesized based on a new synthetic route, then TEC[n] (n = 4, 6, 8) were further modified by reacting with low molecular weight Chitosan (CS) to get three kinds of new Calix[n]arene-Chitosan polymers (n = 4, 6, 8) (C[n]CSP (n = 4, 6, 8)) through Buchwald-Hartwig cross coupling reaction. The structures of the polymers were characterized by FT-IR, SEM, Elemental analyzer and ¹³C SSNMR. And the results found that Chitosan was successfully introduced to Calix[n]arene (n = 4, 6, 8) (C[n] (n = 4, 6, 8)) without any long-chain alkyl between Chitosan and Calixarene. These new polymers are partially substituted calixarene. The substitute degree of C[4]CSP, C[6]CSP and C[8]CSP is 17.75%, 21.08% and 54.53% respectively. And the optimal preparation conditions were discussed and the results were listed as following, molar ratio (1:2), catalyst (0.05 mmol), solvent ratio (1:1.5 (10 mL•1.0 mmol⁻¹)) and reaction time (5h).

KEYWORDS:

• Calix[n]arene
• Chitosan
• Buchwald-Hartwig
• Triflate Ester
• Polymer

Acknowledgments

This work was financially supported by the Inner Mongolia Agricultural University Campus Outstanding Youth Fund (Grant No. 214203025) and the National Natural Science Foundation of China (Grant No. 21064004, Grant No. 21462030).

Conflict of interest

The authors declared that they have no conflicts of interest to this work.