A One‐Pot Approach to Novel Cross‐Linked Polyphosphazene Microspheres with Active Amino Groups

Abstract

Highly cross‐linked microspheres bearing active amino groups on the surface have been successfully synthesized via a single‐step precipitation polymerization of hexachlorocyclotriphosphazene (HCCP) with 4,4′‐diaminodiphenyl ether (ODA) in acetonitrile medium without any added surfactant. The active microspheres were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and differential scanning calorimetry (DSC). The results revealed that the active microspheres had clean surfaces and they were in the size of micrometer range, varying from 0.5 to 2.5 µm. The accessibility of the surface amino groups to further functionalization was confirmed by the reaction of these groups with benzoxy chloride. Interestingly, the content of amino groups can be easily tailored through changing the molar ratio of HCCP to ODA. The effects of the concentration of HCCP and the monomer ratios on the morphology were also discussed.magnified image

Convenient one-pot approach for the preparation of novel atomically thin two-dimensional polymeric nanosheets, and its evolution in aqueous solution

“…The curve indicates a broad endothermic peak at the temperature ranging from 30 1C to 120 1C. The result is different from that of highly crosslinked polymeric microspheres obtained by our previous work, which showed flat curves, indicating highly random crosslinked structure [9]. Here, the endothermic peak indicates a diferent kind structure of microspherical PPM.…”

Facile synthesis of amino‐functionalized polyphosphazene microspheres and their application for highly sensitive fluorescence detection of Fe3+

“…The peak at 1198 cm − 1 (e) could be attributed to the stretching of PN bonds of cyclotriphosphazene, confirming the incorporation of cyclotriphosphazene units in the structure of the microspheres. The absorption at 3354 cm −1 (f) is attributed to the NH stretching vibration of NH 2 , indicating the existence of primary amine groups on the microspheres . The strong absorption peak of PCl bands of HCCP at 601 cm −1 (h) became inapparent after the polycondensation process, meanwhile, the characteristic peak of PN band at 873 cm −1 (h) shows a little blue shift to 938 cm −1 (i) in the products, demonstrating the formation of PNH(Ph) bonds.…”

Synthesis and characterization of polyamine-based cyclophosphazene hybrid microspheres

“…During the last years, the concept of precipitation polymerization was extended to the synthesis of poly(cyclophosphazene) microspheres . Especially, HCCP is a versatile precursor for the development of new microsphere systems, because of the ease of nucleophilic substitution of the phosphorus‐bound chlorine groups.…”

“…Fundamental work has been conducted by Andrianov and coworkers and Huang and coworkers. Although Andrianov's group focuses on the synthesis of hydrogel colloids based on ionic crosslinking of linear, carboxyl‐functionalized polyphosphazenes, Huang's group reports on the synthesis of covalently crosslinked cyclomatrix type colloids under precipitation conditions starting from HCCP and multifunctional phenols or anilines as crosslinking agents …”