Introduction

M-type hexaferrites are functional ceramic materials that have significant contributions to numerous technological and industrial fields. Depending on the alkaline metals (Sr, Ba, Ca, etc.) [1,2,3], these materials have different applications such as microwave and piezoelectric devices, gas-sensors, biomedicine and magnetic resonance imaging (MRI), and photocatalyst for water treatment. One of the most important M-type hexaferrite is SrFe12O19 (SFO). It has received extensive attention owing to its high coercivity, Curie temperature, saturation magnetization, and magnetocrystalline anisotropy [4, 5]. SFO has been utilized in applications for telecommunications, permanent magnets, recording media, and magneto-optical devices [6].

Polyacrylonitrile (PAN), a synthetic vinyl homopolymer, is extensively studied because of its high strength [7], thermal stability [8], abrasion resistance [9], and perfect precursor for carbon fabrication. PAN fibers have a higher melting point (Tm ~ 317 °C) and a high degree of molecular orientation. PAN is also totally non-toxic and appropriate for biological purposes and biomedical applications [10, 11].

Over the past 20 years, PAN has been the focus of various investigations. Researchers are interested in four primary types of PAN: films [12,13,14,15,16], membranes [17,18,19,20,21], composites [22,23,24,25,26,27], and carbon fibers or nanofibers [28,29,30,31]. Each type of PAN-based material requires a specific set of procedures and techniques. Besides all of these reasons to select PAN to form our studied composites, it can absorb different metal ions and assists the absorption materials for applications [32].

Nanomagnetic polymer composites (NPCs) describe a class of materials, where magnetic nanoparticles are embedded in polymer matrixes. Recently, nanomagnetic polymer composites (NPCs) based on polyacrylonitrile (PAN) are of great interest in materials science. These materials are known to offer a wide spectrum of applications due to their distinctive physicochemical characteristics such as improved mechanical properties [33], magnetic properties [34], and increased conductivity [35]. Recent studies on PAN magnetic nanocomposites have demonstrated their enormous potential applications in electronic [36, 37], biological, color imaging [38, 39], magnetic sensors, storage, and high-density magnetic recording systems.

According to the literature, PAN/magnetic fiber was synthesized by incorporating magnetic nanoparticles like iron, cobalt, ferrite [40], or magnetite [41] into the polymer matrix and then electrospinning. Wang et al. [42] synthesized CuFe2O4 fibers that could be used for catalytic oxidation. These fibers had a variable number of CuO nanoparticles on their surface by altering the ratio between the precursors of Co and Fe. In addition, Qing et. al [43] could prepare CoFe2O4/PAN nanofibers with various CoFe2O4 loadings. The results showed a superparamagnetic behavior of CoFe2O4/PAN nanofibers. Liu et al. [44] reported that the Fe3O4/PAN composite, prepared by the electrospinning and coating method, was successful in eliminating tetracycline. Different studies for hexaferrite/polymer composites were reported [45, 46]. La–Co-substituted barium hexaferrite/polyaniline nanocomposites were studied [45]. It was found that the magnetic properties of these composites showed a significant effect on radiation absorption. These results were also found for doped barium hexaferrite/barium titanate/polypyrrole nanocomposites [46].

Although a significant amount of efforts have been made to study PAN/magnetic composites, no more studies on the dielectric, optical, and ferromagnetic properties of these composites have been made yet. Incorporating SFO nanoparticles into the PAN matrix is expected to affect the dielectric, optical, and magnetic properties of the polymer matrix. In this work, we tried to throw light on the physical properties of SFO/PAN composites. To look for any applications of these composites, different characterization techniques are considered such as Fourier transform infrared (FTIR) spectroscopy, field-emission scanning electron microscopy (FE-SEM), and X-ray diffraction (XRD). The dielectric, optical, and magnetic properties were performed, and the results were discussed.

Experimental

Materials and preparation

Polyacrylonitrile powder of molecular weight (Mw ~ 150,000 g/mol) was purchased from (Polymer Laboratories, Essex, UK), as-prepared strontium hexaferrite SrFe12O19 (SFO), and N, N-dimethylformamide (DMF, 99.9%), Aldrich, Germany, was used as the solvent. The chemical reagents used in this work are of analytical grade. They were used directly as received without further purification. The as-prepared SFO nanoparticles were added in different x (wt% 0, 3, 5, 7, and 10) to polyacrylonitrile (PAN) according to:

$$x\,(\mathrm{wt}\%)=\frac{{w}_{f}}{{w}_{f}+{w}_{p}}$$
(1)

where \({w}_{f}\) and \({w}_{p}\) stand for the corresponding weights of SFO and PAN.

The SFO/PAN nanocomposite films were prepared as follows: PAN powder and the desired amount of SFO nanoparticles were dissolved separately each of them in 25 mL of DMF solution. The PAN solution was placed under stirring for 24 h [47] at room temperature (RT) until a clear solution was obtained, while the SFO solution was subjected to ultra-sonication for 3 h at RT to stop the nanoparticles from agglomerating together. The solutions were mixed under ultrasonic stirring at RT for 3 h. Finally, the prepared mixture was placed in Petri dishes, and an 8-h solvent evaporation process was carried out inside an oven set to 70 °C.

Characterization techniques

To study the interactions between the PAN and the SFO nanoparticles a Fourier transform infrared (FTIR) spectrometer (JASCO, FT/IR-6200) was used in the wavenumber range 400–4000 cm−1. The surface morphology of pure and nanocomposite films was investigated by FE-SEM (Carl Zeiss Sigma 500VP, Holland), having an accelerating voltage of 20 kV. XRD patterns of SFO nanoparticles and nanocomposite samples were collected using a PAN analytical's X’Pert PRO having Cu Kα radiation. DSC measurements of the composites were evaluated using Perkin Elmer STA 6000 N2 atom DSC. The thermal decomposition behavior analysis (TGA) was done by TGA (Q50, TA instruments). A Hioki (Ueda, Nagano, Japan) model 3532 High Tester LCR was used for dielectric measurements. The optical spectra were captured using UV–vis spectrophotometer (JASCO 630) at RT in the wavelength (λ) range of 200–1200 nm. The magnetic characteristics of the nanocomposite films were examined at RT and a magnetic field up to ± 20 kOe using a vibrating sample magnetometer (VSM), LakeShore Model 7410.

Results and discussion

Characterizations

The bonding characteristics of the PAN/SFO nanocomposites were analyzed by FTIR spectroscopy. The FTIR spectrum of the pure PAN and PAN/SFO composites is shown in Fig. 1 There are different peaks including the strong stretching vibration of nitrile groups (–CN–) appearing at 2244 cm−1 and the peaks at 2930 and 1453 cm−1 which are corresponding to the stretching vibration and bending vibration of methylene (–CH2–), respectively [48]. The peak at 1670 cm−1 indicates the presence of carboxyl (C=O) groups which may be due to the oxidation of PAN in the air [48]. The peaks at 1251 and 1360 cm−1 are linked to CH and CH2 groups, respectively, which are the fundamental groups forming the backbone chain of the PAN [49]. By the incorporation of nanoparticles into the PAN matrix, the peaks at 2244 and 1095 cm−1 are associated with the nitrile groups which are observed to become stronger and sharper indicating a strong interaction between the PAN and the nanoparticles [50].

Fig. 1
figure 1

FTIR spectra of pure PAN and SFO/PAN composites

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The surface morphology of the SFO nanoparticles and nanocomposite films were tested by FE-SEM as displayed in Fig. 2. SFO shows a hexagonal shape (Fig. 2a). A good dispersion of SFO into PAN and SFO was observed keeping the hexagonal shape of SFO as in the sample 3 wt% (see Fig. 2b). By increasing the SFO content, the morphology of the nanocomposite films has slightly changed may be due to the variation in the viscosity of the polymer and the tendency of the nanoparticles to agglomerate as seen in Fig. 2c, d. It was reported earlier [51] that the shape of the nanoparticles affected the morphology of the polyvinyl alcohol (PVA).

Fig. 2
figure 2

FE-SEM images of (a) SFO nanoparticles and b–d PAN loaded with different SFO content; b 3 wt% FO, c 7 wt% SFO and d 10 wt% SFO

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It is useful to estimate the average particle size (Dav) of the investigated samples by using the FE-SEM images. Figure 3d depicts the histograms of the particle distribution of pure SFO and some SFO/PAN nanocomposites based on ImageJ (Fiji) software. The Dav values of all studied samples are given in Table 1. One noticed a significant difference between the crystal size value of pure SFO nanoparticles and that of Dav because of the agglomeration of the particles in a powder. On the other hand, the Dav of SFO in the composites becomes lower than that of pure SFO. This result could be explained in terms of decreasing the agglomeration of SFO nanoparticles and the separation between these nanoparticles by the polymer chains in composites.

Fig. 3
figure 3

 Histograms for the grain size distribution of a pure SFO nanoparticles, b 3 wt% SFO, c 7 wt% SFO, and d 10 wt% SFO loaded with PAN

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Table 1 Listed are the average particle size (Dav), the degree of crystallinity (Xc%) and different thermal parameters (the initial temperature, Ti, final temperature, Tf, the difference in Tf and Ti, i.e., (∆T), thermic peak, Tp) and enthalpy, ΔH of pure PAN and SFO/PAN nanocomposites
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The XRD patterns of pure SFO and PAN loaded with SFO nanoparticles are displayed in Fig. 4. It is observed that pure PAN and SFO/PAN nanocomposites have the same diffraction peak at 2θ = 17°. According to the literature, this peak indicates the crystalline phase of PAN that is assigned to the (110) plane [52]. The main characteristic peaks of SFO (see the lower panel of Fig. 4) could be easily observed in the XRD pattern of the as-prepared SFO/PAN nanocomposites (see the upper panel of Fig. 4). The intensity of the SFO peaks increased significantly with increasing its content inside the PAN matrix. The average size of crystallites of SFO nanoparticles is estimated based on the Debye–Scherrer formula as [53]:

$$D = \frac{k\lambda }{{\beta {\text{Cos}} \theta }}$$
(2)

where D stands for the grain size in nanometers (nm), λ is the X-ray radiation's wavelength (Cu Kα = 0.14460 nm), k is the Scherrer constant (~ 0.9), θ is the X-ray diffraction angle, and β represents the full-width at half-maximum (FWHM) of the peak. The crystal size of SFO was estimated to be 48.96 nm. This value is different compared to that observed by FE-SEM because of the agglomeration of the nanoparticles. To estimate the effect of nanoparticles on the PAN's crystal structure, the degree of crystallinity (Xc) of the composites was estimated using Hinrichsen’s approach [54]:

$$X_{{\text{c}}} \% = \left( {\frac{{I_{{\text{C}}} }}{{I_{{\text{c}}} + I_{{\text{a}}} }}} \right){ } \times { }100$$
(3)

where Ia is the intensity dispersed by the amorphous fraction, which is the area of the diffractogram outside the peaks, and Ic is the integral intensity of the crystalline fraction, which is the area under the diffraction peaks and background curve. The calculated values of the degree of crystallinity are summarized in Table 1. As seen in Table 1, the Xc value of PAN was altered by adding SFO nanoparticles. Such a result is accepted in composites when crystalline nanofillers are added to semicrystalline polymeric materials. Such a result could be attributed to some reasons either due to the added amount of the crystalline nanofiller to the polymer or the alignment of the PAN polymeric chains [55].

Fig. 4
figure 4

The XRD patterns of pure PAN, and SFO/PAN nanocomposite samples

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The effect of SFO NPs on the thermal stability of PAN was investigated using TGA and DSC techniques. Figure 5 displays the DSC thermograms of pure PAN and SFO/PAN nanocomposites. The pure PAN shows a sharp thermic peak at (Tp ~ 576 K); this peak is due to an exothermic reaction occurring due to the cyclization of nitrile groups [56]. By increasing the SFO content, this peak is shifted toward lower temperatures. The relative parameters obtained from the DSC curves are listed in Table 1. As seen from Table 1, there is a decrease in enthalpy value with increasing SFO content which indicates the intensified disorder with the addition of the SFO NPs.

Fig. 5
figure 5

DSC thermograms of pure PAN and SFO/PAN nanocomposite samples

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TGA was used to check the thermal stability of pure PAN and SFO/PAN nanocomposites. The TGA curves are displayed in Fig. 6. The degradation process of all samples can be expressed as five stages. In stage I, a slight loss of mass took place owing to the water molecules and decomposition of low molecular weight components [57]. In the second II and third III stages, the weight loss in the temperature between 543 and 643 K, the nanocomposites have a smaller weight loss rate compared to that of pure PAN which leaves a residual weight of 66% up to 643 K. Besides, the nanocomposite samples showed a residual weight of 78.3% indicating that they have easily undergone cyclization reaction compared to pure PAN. Such results are consistent with the results from the DSC analysis. The fourth stage IV, between 643 and 738 K, corresponds to 12% weight loss of nanocomposites and 8% weight loss of pure PAN owing to PAN’s thermal degradation [58]. In the final stage V, 4–5% of weight loss was seen for all studied samples due to pyrolytic degradation of PAN leaving residual masses near 873 K, 58%, 60.3%, 62.9%, and 64.1% for pure PAN, and SFO/PAN nanocomposites (5,7, and 10 wt%), respectively. This is evidence that the samples containing higher SFO content have greater thermal stability compared to that of pure PAN. Similar results were reported for polyhedral oligomeric silsesquioxane (POSS) nanoparticles doped polypropylene [59].

Fig. 6
figure 6

TGA thermograms of pure PAN and SFO/PAN nanocomposite samples

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Dielectric properties

The dielectric properties of the as-prepared PAN and SFO/PAN composites were studied. One noticed that the dielectric permittivity (ε' = d C/εoA, where C is the capacitance, d is the sample thickness, εo is the free space permittivity, and A is the sample cross-sectional area) decreases with increasing the frequency for all samples as shown in Fig. 7a–d. In addition, the ε' showed high values for all temperatures at lower frequencies; then, it started to decrease again as the frequency increased because the dipoles were no longer able to follow the field and hence their contribution to the polarization decreased. The ε′ of PAN is considerably enhanced by doping with SFO nanoparticles. The increase in ε′ for PAN can be ascribed to the formation of extra molecular dipoles in the nanocomposites.

Fig. 7
figure 7

The variation of ε′ as a function of frequency for pure PAN and SFO/PAN nanocomposites at different temperatures a 333 K, b 353 K, c 383 K, and d 423 K

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Figure 8a–d displays the temperature dependence of ε′ for pure PAN and PAN loaded with SFO nanoparticles at some selected frequencies. The behavior of ε′ can be explained as follows: at lower temperatures, the number of dipoles rotating in parallel with the applied electric field was limited as the thermal energy absorbed by the polymer is small [60]. By increasing temperature the polymer’s viscosity reduced and the dipoles gain enough energy to be easily oriented with the applied electric field, thus ε′ increased and reached a maximum near 373 K related to a peak is observed due to the micro-Brownian motion corresponding to α-relaxation process [61].

Fig. 8
figure 8

The temperature dependence of dielectric permittivity, ε′, for pure PAN and some SFO/PAN composites at different selected frequencies

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The value of the dielectric loss is significant for capacitor applications. The usage of dielectric materials in high-performance capacitor applications could be constrained by the high levels of dielectric loss. Figure 9a–c shows the variation of the dielectric loss, ε″, where ε″ = ε′ tan δ), for pure PAN and some nanocomposites at some selected temperatures. One noted that ε″ increased rapidly at lower frequencies revealing the existence of electrode polarizations [62]. On the other hand, as the frequency increases, the amount of polarization, by charge accumulation, reduces and then the value of the dielectric loss decreased.

Fig. 9
figure 9

a–c The frequency dependence of dielectric loss, ε″, for pure PAN and some SFO/PAN nanocomposite samples at different temperatures

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Figure 10a–d displays the temperature dependence of the ε″ for pure PAN and some nanocomposites at some selected frequencies. The ε″(T) shows a relaxation peak due to α-relaxation in PAN. This peak appears in the temperature range from 360 to 400 K [63] because of the micro-Brownian motion of segments of polymeric chains. Such peak becomes broader and shifts to a higher temperature side for higher frequencies. This broadness indicates dispersion in relaxation time as a result of the increase in the density of dipoles.

Fig. 10
figure 10

a–d The temperature dependence of dielectric loss, ε″, for pure PAN and some SFO/PAN nanocomposites at different selected frequencies

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To analyze the dielectric behavior of the nanocomposite samples and prevent the impact electrode polarizations, the electric modulus can be used [64]:

$$M^{*} = M^{\prime } + iM^{\prime \prime } = \frac{1}{{\varepsilon^{*} }}$$
(4)
$$M^{*} = \frac{{ \in^{\prime}}}{{ \in^{^{\prime}2} + \in^{\prime \prime 2} }} + i\frac{{ \in^{\prime\prime}}}{{ \in^{^{\prime}2} + \in^{\prime \prime 2} }}$$
(5)

where M′ and M″ represent the real and imaginary parts of the electric modulus, respectively. The variation of M′ with the temperature at some selected frequencies is shown in Fig. 11a–d. It is noticed that by increasing temperatures, the values of M′ decreased because the dielectric permittivity is thermally activated [65]. This result is consistent with the increase of ε′ of pure PAN with adding the SFO nanoparticles.

Fig. 11
figure 11

a–d The variation of dielectric modulus, M′, with temperature for pure PAN and SFO/PAN nanocomposites at some selected frequencies

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It is useful to throw light on the relaxation process in PAN after adding SFO nanoparticles. Figure 12a–e displays the frequency dependence of M′′ for some nanocomposites as an example. A relaxation peak known as the conductivity-relaxation peak of the mobile ions (αc-relaxation) could be seen [66]. A possible explanation for the low-frequency region of the αc-relaxation is the DC conductivity resulting from charge carriers that are continuously hopping over long distances. In the high-frequency region, the ions are constrained to their potential wells corresponding to a short-range motion. Consequently, the M″ relaxation peak results from the transition from long-range to short-range mobility [67]. Also, the M peak shifts toward higher frequencies as temperature increases due to an increase in the density of dipoles contributing to the relaxing process.

Fig. 12
figure 12

a–e The frequency dependence of dielectric modulus, M″, for pure PAN and SFO/PAN nanocomposites at different temperatures

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Based on Fig. 13, the activation energy of the relaxation was determined using the maximum frequency, fmax, described by the Arrhenius equation [68]:

$${f}_{max}= {f}_{o}\mathrm{exp}\left(-\frac{{E}_{\mathrm{a}}}{KT} \right)$$
(6)

where Ea is the activation energy, k is the Boltzmann constant, and fo is a distinctive constant parameter for a specific relaxation process. Figure 13 depicts the change of fmax for pure PAN and some SFO/PAN nanocomposites versus 1000/T and the calculated values of Ea are shown in Table 2.

Fig. 13
figure 13

The variation of ln(fmax) versus 1000/T for pure PAN and some SFO/PAN nanocomposites

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Table 2 Listed the activation energy, Ea, and the ac conductivity (Ω−1 m−1) for pure PAN and SFO/PAN nanocomposites at different temperatures
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The ac conductivity values of pure PAN and SFO/PAN nanocomposites are calculated as:

$$\sigma_{ac} = \omega \varepsilon_{o} \varepsilon^{\prime}\tan \delta = 2\pi f\varepsilon_{o } \varepsilon^{\prime\prime}$$
(7)

where ω is the angular frequency. The calculated values of the ac conductivity are shown in Table 2. As seen, the conductivity increased by increasing the SFO content. This might be attributed to the formation of conductive networks throughout the composite as a result of the effect of SFO nanoparticles. These networks enable the charge carriers to hop from one site to another within the nanocomposites.

Optical properties

The UV–vis spectra of radiation absorption and transmittance (T) of pure PAN and SFO/PAN nanocomposites are presented in Fig. 14a–b. The absorbance spectra of films show a sharp edge at the ultraviolet region at 300 nm with low absorption at the long wavelength region. This edge is probably caused by n—π* electronic transition [69]. The films appear low absorption at the long wavelength region. Also, the absorbance increases with increasing the content of SFO nanoparticles SFO. On the other hand, the transmittance of PAN decreased by adding SFO nanoparticles because they act as scattering sites for the incident photon. This means that the transparency of the polymeric materials can be changed by nanofillers. It is also noticed that T increased with increasing λ. The reason for this increase is the energy of the incident photons, which can excite the electrons from the valence band to the conduction band.

Fig. 14
figure 14

a The absorbance (b), the transmittance spectra of pure PAN and PAN loaded with 3, 5, 7 and 10 wt.% of SFO nanoparticles

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The refractive index (n) is calculated from the values of the reflectance, R, according to the relation: [70]

$$n=\frac{(1+\sqrt{R})}{(1-\sqrt{R})}$$
(8)

while the variation of n with λ can be expressed as [71]:

$$\frac{{n_{\infty }^{2} - 1}}{{n^{2 } - 1}} = 1 - \left( {\frac{{\lambda_{o} }}{\lambda }} \right)^{2}$$
(9)

where n∞ is the refractive index at infinite wavelength, and λo is the average interband oscillator wavelength. Figure 15 represents the variation of (n2−1)−1 against λ−2. The fitting parameters, n∞ and λo, are given and listed in Table 3. From these parameters, the average oscillator strength (So) where So = \(({n}_{\infty }^{2}-1)/ {\lambda }_{o}^{2})\). It is noticed that the refractive index of PAN was changed by adding SFO nanoparticles to the PAN polymer matrix which is useful for applications. Similarly, the values of other optical parameters are So and λo.

Fig. 15
figure 15

Plot of (n2−1)−1 versus λ−2 for pure PAN and SFO/PAN nanocomposites

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Table 3 Listed are some optical parameters of pure PAN and SFO/PAN nanocomposite samples
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Magnetic properties

The room-temperature hysteresis loops of SFO nanoparticles and PAN loaded with different ratios of SFO are shown in Fig. 16a–d. The magnetization curves revealed that the as-prepared SFO/PAN nanocomposites exhibit ferromagnetic behavior. The magnetization loops are not saturated within the studied range of the applied magnetic field. Different magnetic parameters for the investigated samples are given in Table 4. It was observed from Table 4 that the Mr values are enhanced with increasing SFO content owing to the magnetic nature of these nanofillers. The coercivity of the samples slightly changes with the change in the SFO content.

Fig. 16
figure 16

a–d The magnetic hysteresis loops of SFO nanoparticles and some SFO/PAN nanocomposites at RT

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Table 4 The magnetic properties of pure SFO and PAN/SFO nanocomposite samples
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Stoner–Wohlfarth (S–W) model was used [72, 73]:

$$M={M}_{s}\left(1-\frac{\beta }{{H}^{2}}\right)$$
(10)

where β is a parameter related to the magnetocrystalline anisotropy of the samples. Figure 17a, b displays the plots of M against 1/H2 for pure SFO and all nanocomposites. From the linear fitting of Eq. 10, Ms was estimated by extrapolating M versus 1/H2 to zero. The values of Ms and β are given and listed in Table 4. SFO nanoparticles revealed a high value of saturation magnetization (Ms) (see Fig. 17a), whereas, in the case of SFO/PAN nanocomposites, the Ms depends on the content of the nanoparticles. This can be explained owing to the existence of a diamagnetic phase of PAN in the nanocomposites, which may affect the uniformity of magnetization by excluding the surface magnetic moment. Also, the Mr/Ms ratio is related to the grain size and the distribution of particles [74]. It was found to be (Mr/Ms > 0.5) for the samples under study. The values of the crystal size and magnetic properties of SFO are comparable with those of similar published materials [75].

Fig. 17
figure 17

A plot of M as a function of 1/H2 for pure SFO (a) and (b) the as-prepared SFO/PAN nanocomposites. The solid lines represent the fitting, according to Eq. 10

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Conclusions

Strontium hexaferrite (SFO) nanoparticles were prepared and incorporated into a polyacrylonitrile (PAN) matrix. The impact of SFO on the dielectric, optical, and magnetic properties of PAN was investigated. The XRD spectrum for PAN shows a semicrystalline structure while the nanocomposites exhibited the peaks of the SFO nanofillers. The FE-SEM showed a good dispersion of SFO on the surface of PAN, especially at low content. DSC data also showed that SFO/PAN nanocomposite samples had a broader thermic temperature range and a lower rate of evolving heat. The TGA results exhibited that with increasing the SFO content, the SFO/PAN nanocomposites are more thermally stable than pure PAN.

The incorporation of the SFO nanoparticles enhances the dielectric permittivity and ac conductivity promising for high-performance dielectric capacitors. Within the studied range of temperature and frequency, a relaxation process was observed for pure PAN and PAN loaded with SFO nanoparticles. Based on the optical properties, the transparency of PAN was changed by adding SFO nanoparticles because the absorption and transmittance were changed. Also, the refractive index of pure PAN increased with loading with SFO nanoparticles. Different optical parameters are given.

Finally, different magnetic parameters were given for pure SFO and SFO/PAN nanocomposites. It is useful to keep the magnetic properties of a polymeric matrix by adding some magnetic nanoparticles such as SFO. All nanocomposites exhibited ferromagnetic behavior at RT. All together. i.e., the outcome results of this work are, the physical properties of PAN can be controlled by adding a suitable amount of SFO nanoparticles. Therefore, the studied nanocomposites could be useful for applications such as capacitors, anti-coating reflection, and recording data, depending on the specific change in the physical properties of the pristine samples.