Modified cotton polyester fabric with nanostructured ferromagnetic microwire characterized by low flammability
The aim of this study is to substantiate experimentally the flammability reduction of cotton polyester fabric with nanostructured ferromagnetic microwire (NFMW) after its modification by impregnating the fabric with an aqueous solution of calcium chloride (CaCl2). The X-ray diffraction studies of non-modified and modified samples of cotton polyester fabric with nanostructured ferromagnetic microwire (NFMW) using an aqueous solution of calcium chloride (CaCl2) was conducted.
X-ray diffraction study of NFMW cotton polyester fabric samples was perfomed by DRON-3 X-ray diffraction meter using monochromic CuKα-irradiation (wavelength l = 1,5417737 Å).
The block diagram of the X-ray diffraction meter is shown in Fig.3. Measurements were made according to the following algorithm:
1. Put a sample on the diffractometric stand.
2. Bring the diffraction meter counting complex in the required position
3. Charge a chart tape into the self recorder.
4. Set the required voltage and current of the roentgen tube
5. Switch on the self-recorder and X-ray source
6. Rotate the sample around the goniometry axis
7. Switch off the self- recorder after rotation of the sample ceases
8. Determine the crystallographic deviations in the sample.
The diffraction spectra were recorded from point to point with 0,04° step and 2 s exposition in every point of the measurement. The angle range varied within 10°…90°, and a record speed was equal to 1,000 cps [3, 4].
In paper  it was shown that NFMW cotton polyester fabric contains silicon oxides (SiO2, Si5O10), brucites (D1,988MgO2, MgH2O2) and ferrous niobate (F6FeNb). Fig.4 presents X-ray diffraction pattern of NFMW cotton polyester fabric after the treatment by open fire at temperature of at least 1,400°С.
Identification of phase maxima was performed by "Crystal Impact MATCH! v. 1.11" software. The identified phase maxima were compared with the reference phase maxima contained in the "Crystallography Open Database".
It is clear from Fig.4 that the basic components of the remainder after thermal treatment with open fire of the NFMW cotton polyester fabric are calcium silicate (Ca2O4Si) and tilleulitis (C2Ca5O13Si2). The X-ray diffraction pattern of the NFMW cotton polyester fabric impregnated with 50% aqueous solution of calcium chloride (CaCl2) is shown in Fig.5, and X-ray diffraction pattern of the material after the thermal treatment with open fire is presented in Fig.6, where the fire temperature was at least 1,400°С.
On the basis of the X-ray diffraction patterns study it was established that impregnating of the NFMW cotton polyester fabric with an aqueous solution of calcium chloride (CaCl2) has led to incorporating of different complexes of mineral remains based on Ca, Al, Fe, Mg and Zr in the interfibre space.
Thermal treatment with open fire of this material resulted in formation of calcium silicate (Ca2O4Si) (as in case of the thermal treatment with an open fire of the initial fabric) and such minerals like vesuvianite
(Al5,2Ca9,16Cl0,23F1,674Fe0,62H2,6Mg0,516Na0,04O371Si8,915Ti0,64), pyroxferoite (Ca0,94Fe6,06O21Si7) and trisodium phosphate dipotassium triphosphidosilicate (K2Na3P2Si).
Thus, it is possible to conclude that the basic contribution to the formation of such materials when treated with open fire is determined by interaction between silicon oxide contained in the microwire glass shell and roentgen-amorphous calcium and carbon contained in organic threads.
Absence of open fire at high-temperature treatment may be explained by decreasing of the sample temperature due to evaporatiion of water contained in it (up to 120% of the dry material weight) and formation of ceramic inclusions that reflect the IR high temperature heating.