SCIENTIFIC AND TECHNOLOGICAL FOUNDATIONS OF USING FE(CH₃COO)₂ PRECURSOR IN THE PREPARATION OF PA-6-BASED NANOCOMPOSITES FILLED WITH IRON NANOPARTICLES
Keywords:
PA-6, iron(II) acetate, Fe(CH₃COO)₂, precursor, nanocomposite, XRF, FTIR, UV analysis, reflectance, Fe₂O₃-equivalent.Abstract
The paper substantiates the use of iron(II) acetate, Fe(CH₃COO)₂, as a precursor for iron-containing PA-6 nanocomposites. Stoichiometric calculation gives a theoretical Fe content of 32.11 wt.% for anhydrous Fe(CH₃COO)₂ versus 9.03 wt.% for Fe(oleate)₂; therefore, approximately 3.56 times more iron-oleate precursor is required to introduce the same amount of iron. Literature data report decomposition of iron(II) acetate at 190–200 °C, which is thermally compatible with the 225–240 °C processing window used for the PA-6 system. However, the exact crystalline phase formed under these conditions cannot be assigned without XRD/TEM evidence. XRF analysis of ten experimental samples showed an Fe₂O₃-equivalent range of 0.0398–53.1 wt.%. The PA-55 sample contained 8.15 wt.% Fe₂O₃-equivalent with a calculated PA-6 fraction of 91.062 wt.%; its FTIR spectrum retained the Amide I region while UV optical measurements showed reduced reflectance. The relationship between reflectance minimum and Fe₂O₃-equivalent was monotonically inverse (Spearman ρ = −0.685, p = 0.029). A three-stage XRF → FTIR → UV quality-control approach is proposed.
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