Synthesis and characterization of polyamine-based cyclophosphazene hybrid microspheres

Abstract

Starting with hexachlorocyclotriphosphazene (HCCP) and branched polyethylenimine (bPEI) crosslinked cyclomatrix polyphosphazene poly(HCCP-co-bPEI) microspheres are prepared by precipitation polymerization in acetonitrile at 50 C under ultrasound irradiation. The influence of varying reagent ratios on the chemical composition, morphology, and physical and chemical properties of the microspheres is investigated. Furthermore, the microspheres are characterized by Fouriertransform infrared spectroscopy, dynamic light scattering (DLS), X-ray photoelectron spectroscopy, elemental analysis, as well as 31 P MAS NMR. FESEM and DLS analysis show microspheres of smooth and spherical shape which swell both in water and ace-tonitrile. The particle diameters in the dry state range from 0.4 to 0.9 lm, but due to swelling a size increase between 45 and 140% is observed depending on the chemical composition and the solvent medium. The thermal stability of the microspheres ranges from 262 to 351 C. The presence of reactive amine groups on the surface is proven by electrophoretic mobility measurements and chemical modification with two model compounds.

Synthesis of Negative‐Charged Metal‐Containing Cyclomatrix Polyphosphazene Microspheres Based on Polyoxometalates and Application in Charge‐Selective Dye Adsorption

“…[20] Compared with the 31 P chemical shift of HCCP in CDCl 3 ( Figure S6, Supporting Information), there are mainly three different types of phosphorus atoms in the resultant MCPMs ( Figure 1D). According to the literature [20,24] and our experiment data, the peak around 3 ppm can be assigned to disubstituted phosphorous atoms with different chemical environments, while the signals at 19 and 21 ppm can be attributed to the mono-substituted and non-substituted phosphorus, respectively.…”

“…Cyclomatrix polyphosphazene (CP) was developed by Tang and coworkers, which can be easily synthesized from precipitation polymerization based on nucleophilic substitution from hexachlorocyclotriphosphazene (HCCP) and di‐functionalized monomers . Due to the facile preparation and easy control of the morphology of the resultant CP, different monomers such as fluorescein, l ‐cysteine methyl ester, ferrocene, and dendrimers have been introduced to the CP system. These CPs are widely used in bio‐imaging and as catalysts, absorbents, photothermal therapy agents as well as in energy storage.…”

“…The molecular design of MCPMs was based on the precipitation polymerization of di‐functionalized monomers with HCCP in the presence of suitable base, such as triethylamine(TEA) and N , N ′‐diisopropylethylamine (DIPEA). As mentioned earlier, different di‐functionalized monomers, such as luminescent fluorescein, bioactive l ‐cysteine methyl ester, redox active ferrocene, even branched polyethylenimine, have been introduced into CPs. However, one may notice that almost all of the prepared CPs are neutral.…”

“…[14] Several www.advancedsciencenews.com www.mrc-journal.de triethylamine(TEA) and N,N′-diisopropylethylamine (DIPEA). As mentioned earlier, different di-functionalized monomers, such as luminescent fluorescein, [21] bioactive l-cysteine methyl ester, [22] redox active ferrocene, [23] even branched polyethylenimine, [24] have been introduced into CPs. However, one may notice that almost all of the prepared CPs are neutral.…”

Novel Cyclomatrix-Type Polyphosphazene Microspheres Crosslinked With Octachlorocyclotetraphosphazene: Preparation and Characterization

“…Recently, synthesis, characterization and application studies of cyclomatrix polyphosphazene nano/microspheres via precipitation polymerization technique have accelerated [1][2][3][4][5][6][7][8]. This technique is basic, rapid and has some advantages such as no need to any stabilizer or surfactant molecules.…”