Nanoscience and Nanotechnology

p-ISSN: 2163-257X    e-ISSN: 2163-2588

2016;  6(2): 17-23



Preparation and Characterization of ZnO/polystyrene Nanocomposite Films Using Ultrasound Irradiation

Alwan N. Jassim 1, Riyadh M. Alwan 1, Quraish A. Kadhim 2, Ahmed A. Nsaif 3

1Corporation of Research and Industrial Development, Iraqi Ministry of Industry and Minerals, Iraq

2Chemical and Petrochemical Research Center, Corporation of Research and Industrial Development, Iraqi Ministry of Industry and Minerals, Iraq

3Environmental Research Center, University of Technology, Ministry of High Education Baghdad, Iraq

Correspondence to: Alwan N. Jassim , Corporation of Research and Industrial Development, Iraqi Ministry of Industry and Minerals, Iraq.


Copyright © 2016 Scientific & Academic Publishing. All Rights Reserved.

This work is licensed under the Creative Commons Attribution International License (CC BY).


In the present work, thin films containing nano zinc oxide and polystyrene were prepared via sol-gel process followed by film casting with 5 wt% concentration of ZnO. The prepared nano composite films were characterized using atomic force microscopy (AFM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) analysis, differential scanning calorimeter (DSC) and UV-Vis analysis. Atomic force microscopy showed that ZnO nano particles were homogeneously dispersed in the polystyrene matrix, and root mean square (RMS) was 5.24 nm for neat polystyrene and found to be 6.2 nm for ZnO/polystyrene composite film. The introduction of ZnO nano particles increased the glass transition temperature by 6.81°C. The transmittance and absorbance of UV-Vis light exhibited normal spectra for these films. The X-ray diffraction pattern verified the hexagonal structure of nano ZnO and FT-IR spectra evidenced the existence of ZnO nano particles and polystyrene in ZnO/Ps composite film.

Keywords: Sol-gel, ZnO nanoperticles, Polystyrene, AFM, XRD, DSC, FT-IR and UV-Vis

Cite this paper: Alwan N. Jassim , Riyadh M. Alwan , Quraish A. Kadhim , Ahmed A. Nsaif , Preparation and Characterization of ZnO/polystyrene Nanocomposite Films Using Ultrasound Irradiation, Nanoscience and Nanotechnology, Vol. 6 No. 2, 2016, pp. 17-23. doi: 10.5923/j.nn.20160602.01.

1. Introduction

Nowdays, a lot of work has been done on organic/ inorganic nanocomposite films. A combination of organic and inorganic materials results in the formation of composites that show the properties of both components, creating wide scope of applications in science and technology. Besides, improvements of many properties are achieved at a very low loading of nanoinorganic materials, compared to micro-sized fillers [1-6].
Among many inorganic materials, ZnO is specifically interesting owing to its variety of application fields like solar cells, gas sensors, Varistors, luminescent devices and antibacterial activity. When the size of ZnO crystal decreases to nano scale, it can have mechanical, optical, electrical, thermal properties and antibacterial activity quite different from the bulk [7-16]. Nano particles are much more reactive than larger particles because of their small size and large surface area. They have many advantages like high surface to volume ratio, good chemical, biocompatibility and easy fabrication which makes them appropriate for preparation hygienic surfaces [17-24].
The polymer matrix composites are very important as they are most widely used because of their lightness, ease of fabrication and a variety of other properties [25-31]. ZnO nanoparticles can be prepared easily via sol-gel or wetchemical method, thermal decomposition and chemical vapor route [32-37].
A great deal of research has been focused on the development of ZnO/polymer nano composite materials using different polymer systems. Polystyrene polymer is transparent thermoplastic material, with lots of prospects for making composite material with nano structured ZnO. Introduction of ZnO filler into polymeric matrices can modify their optical, electrical and other properties [38-44].
The present work is a simple attempt to prepare and characterize of ZnO/polystyrene nano composite thin films via mixing and casting process.

2. Experimental Section

All chemicals were purchased from a Merck company and used without further purification. The solutions were prepared by using distilled water. Preparation of nano zinc oxide are illustrated else where [45]. In brief, gel of zinc oxide was prepared as follows: 12.6g of zinc acetate dihydrate was dissolved in 400ml of distilled water, then 600ml of ethanol was added slowly at 50°C, and 6ml of H2O2 (47%) was added dropwise then mixed for one hour. Then, this solution was placed in an ultrasonic vessel with rated output power of 750 W and frequency 24 kHz, to get clear solution and keptuntil use. Sonics vibra cell from USA sonics and materials, INC company was used in this experment. For comparison purpose, we prepared nano zinc oxide powder by drying part of the above solution in oven for several hours at 80°C.
To prepare ZnO/polystyrene nano composite film, in a typical experiment, 2g of polystyrene (Sabic company) was dissolved in 50ml of toluene and then directly added into the prepared gel of ZnO. The concentration of ZnO was taken as 5 wt% to polystyrene. The solution mixture was then poured into 10x15 cm clean and dry glass mold. The solvents were evaporated slowly in a dust free chamber at room temperature, then composite films were obtained after evaporation and then heated for several hours at 80°C to remove any solvents and to convert zinc gel into zinc oxide nano particles. Also, neat polystyrene film without nano material was prepared similarly to this procedure with similar thicknesses.

3. Results and Discussion

The prepared composite thin films were flexible crack free and the achievement of transparency can be readily seen by nacked eyes. Figure 1 shows the photograph image of the film cast from toluene with 130 µm thickness in average.
Figure 1. Photograph of the nanocomposite film prepared by casting. The thickness of the film is around 130 µm. The amout of ZnO was fixed to 5 wt%
AFM imaging technique has proved to be effective to study the morphology of ZnO/PS nanocomposite films. Due to soft polystyrene polymer surface we used tapping mode atomic force microscopy (AFM) at scan rate of 0.8 Hz using (INTEGRA) Scanning probe microscope from Russian NT-MDT company.
AFM images obtained for the nano composite films in all the samples verified spherical morphology for the ZnO nanoparticles. Figure 2 shows the AFM 2-D image and corresponding 3-D image of the ZnO /Ps nano composite film in a scan area of 2X2µm. Also, AFM analysis shows good distribution of ZnO nanoparticles in polymer film. Besides, a large amount of nano pits was found on polystyrene film surface. The nanoparticles had a size distribution centered around70 nm, with a few particles around 80nm, resulting in an average size of 70 nm. The Root mean square (RMS) roughness of the composite filmwere found to be 6.2nm, and was 5.24 nm for plain polystyrene film.
Figure 2. AFM 2-D image (a) and its corresponding 3-D image (b) of the ZnO/PS nano composite film in a scan area of 2X2 µm, and (c) shows good dispersion of nanoparticles in PS matrix
FT-IR spectroscopic studies
The FT-IR spectra of ZnO/PS nano composite film are shown in figure 3. The FT-IR spectra show absorption at 1760.66, 1532.97 and 1369.12 cm-1 which are characteristic vibration bands of aromatic C=C contributing from styrene units. The absorption peaks at 3028 cm-1 and 2849.81 cm-1are assigned to the asymmetric and symmetric stretching vibrations of –CH2 group respectively. The absorption bands ranging from 3600-3028.02cm-1 are assigned to aromatic C-H stretching vibration. In addition, the main peak of ZnO nanoparticles in ZnO-PS nano composite film was observed at 419.07 cm-1. These results were consistent with previous works reported by others [39, 30, 31].
Figure 3. FT-IR transmission spectra of ZnO/PS nanocomposite film
X-ray diffraction can be used for characterization and identification of nano particles. In this study, XRD patterns were taken on XRD SHMADZU 6000 diffractometer equiped with Cu-Ka (1.5418 A°) radiation operation at 40kv and 30mA. Scanning was carried out in the 2θ range from 5° to 80° The powder samples were scanned at a scan speed of 5° per minute, and the film samples, at a scan speed of 2° per minute.
The XRD pattern of ZnO/PS nano composite film is shown in Figure 4. The pattern shows a broad, noncrystalline peak of PS, and more intense and crystalline diffraction peaks of ZnO. The diffraction peaks with 2θ values of 31.74°, 36.83° and 47.62° corresponding to (100), (101) and (102) planes which indicate the hexagonal structure of ZnO. The average particle size is determined from the X-ray lines broadening using the scherrer equation:
β=k λ/d cosθ
Where β: is the full width at half maximum (f w h m) in radians of the diffraction peak,
λ: is the X-ray wavelength,
k: is a constant (0.89);
θ: is the Bragg angle of the peak and
d: is the average particle size.
Figure 4. XRD pattern of ZnO/PS nanocompsite film prepared at room temperature
The average particle size found to be 38nm.
No characteristic peaks of impurities are found. This revealed the high purity of the sample. We believe that the presence of ZnO produces neither new peaks nor peak shifts with respect to PS. This indicates that nano ZnO filled PS composites consist of two phase structures. The result is in accordance with the result of Jeep (2012) [25].
The UV-Vis absorbance and transmittance spectra of polystyrene thin film and of the ZnO/PS nano composite films were recorded on Spectro UV-Vis Double Beam type UV-3500 spectrophotometer in the wavelength range from 190 nm to 900 nm. The transmittance spectra of plain polystyrene and ZnO/PS nano composite films, with similar thicknesses, are shown in Figure 5. The composite film shows transparency around 80.3% in the visible region, comparing with 85.3% for plain polystyrene film in the same region. The absorbance spectra of the composite thin film and the plain polystyrene are shown in Figure 6. It is clear that dramatic change in the absorption of the ZnO/PS nanocompsite film can be observed and the spectra exhibited strong absorption around 355nm, which indicates almost uniform size of the nano particles. For comparison purpose, the absorption spectrum of ZnO gel is shown in Figure 7. Our results are in agreement with those of other authors [46-49].
Figure 5. UV-Vis transmission spectra of the ZnO/PS nanocomposite film, and of plain polystyrene film
Figure 6. UV-Vis absorption spectra of ZnO/PS film and PS film at room temperature
Figure 7. Absorption spectrum of ZnO gel
DSC analysis was performed with (DSC type shimadzu- DSC 60) with plain polystyrene film and ZnO/PS nanocomposite film. The samples were heated from room temperature to 400°C at the heating rate of 5°C per minute under a constant flow of argon gas.
The glass transition temperature (Mid Point), Tg, of plain polystyrene film is found to be nearly 82.45°C and increased to 89.26°C for ZnO/PS nanocomposite film. This indicates that presence of ZnO nanoparticals does not reduce the intermolecular H-bonding interactions to such a great extent that much thermal energy is required for transformation from glassy to rubbery state. In other words, at embient temperature the ZnO/PS film exists in glassy state. Almost similar type of discussion has been reported by Sunil B. et al [46]. The thermograms of ZnO/PS films is shown in Figure 8.
Figure 8. DSC thermogram of ZnO/PS nanocomposite film

4. Conclusions

We have demonstrated the synthesis of ZnO/polystyrene nanocomposite film with 5% of ZnO through the mixing process. The nano zinc oxide improved the thermal properties of the prepared composite film and increased the root mean square of their surfaces, beside a dramatic change in the absorption intensity in the UV region. Also, the XRD, FT-IR and UV-Vis analyses exhibited the high purity of the prepared nanocomposite film. Further work remains to be done on various other thin film combination uesing different materials.

5. Funding / Support

The authors wish to extend their gratitude to the Iraq ministry of industry and minerals for financial support.


[1]  Chitra, K. and Annadurai G., Antimicrobial activity of wet chemically engineered spherical ZnO nanoparticles on food borne pathogen, International food Research Journal 20 (1): 59-64 (2013).
[2]  Radyum, I., Putri, R. I., and siswanto, S., Effect of PH variation on particle size and purity of Nano zinc oxide synthesized by sol-gel method; International Journal of Engineering and Technology, Vol: 12, No. 6, 5-9(2012).
[3]  Klingshirn; Zno: Material, Physics and Application. Cheme Phy Chem 8: 782-803(2007).
[4]  He H., Yang V., and Ye Z. b. Layer-structured ZnO nanowire arrays with domina surface and acceptor-related emissions- Materials Letters 65: 1351-1354(2011).
[5]  Emamifar A., Kadivar M., and Zad S.S.; Evaluation of nanocomposite packaging containing Ag and ZnO on shelf life of fresh orange juice, Innovative-Food Science and Emerging Technology 11: 742-748(2010).
[6]  Ghotamhosain Mohammadnezhad, Mohammad Dinari, Roozbeh Soltani and Zahra Bozorgmehr; Thermal and mechanical properties of novel nanocomposite from modified mesoporous carbon FDU-15 and poly(methyl methacrylate), Appl. Suface science, Vol. 346(2016) pp. 182-188.
[7]  L. Vermeiren and F. Devlieghere; Effectivness of some recent antimicrobial packaging concepts; Food Add. contamin. 19, 163 -171 (2002).
[8]  L. Vermeiren, F. Devlieghere, M. Beest and N. kruijf; Development in the active packaging of foods; Trends food Sci. Technol. 10(3): 77 – 86 (1999).
[9]  A. Brody, E. strupinky, and L. R. Kline; Active packaging for food application; Lancaster: Techno publishing Co., Inc. 218 (2001).
[10]  P. Suppakul, J. Mitts, and K. Sonneveld; Active packaging technologies with an emphasis on antimicrobial packaging and its applications; Journal of food science, 68(2), 408-420 (2003).
[11]  J. K. Behera; Synthesis and chercterization of ZnO Nano- particales, M. Sc. Thesis, National Institute of Technology, India (2008).
[12]  D. W. Chae and B. C. Kim; Characterization of pstl ZnO nanocomposites prepared from solution mixing, polymers for advanced technologies, 15, 840-850(2005).
[13]  C. M. Mac, Y. J. Chen and H. C. Kuan; Polystyrene nanocompsite materials-preparation mechanical, electrical and thermal properties, J. Appl. Polym. Sci., 100, 505-515 (2006).
[14]  M. Saleem, L. Fang and C. Y. Kong; Simple preparation and characterization of Nano-Crystalline Zinc Oxide thin film by Sol-Gel method on glass substrate, World Journal of condensend Matter physics, 2, 10-15(2012).
[15]  K. R. Agnieszka and J. Teofil; Zinc oxide-from synthesis to application: A review, Materials, 7, 2833-2881(2014).
[16]  R. Rajendran, C. Balakumar and E. M. Rajesh; Use of zinc oxide nano particles for production of antimicrobial textiles, International Journal of Science and Technology, 2(1), 202-208 (2010).
[17]  Kolekar T.V., Yadav H.M. and Bandgar S.S.; Synthesis by sol- gel (method and characterization of ZnO nanoparticles), Indian streams research journal, Vol. 1No. 1, pp. 1-4(2011).
[18]  Ranvir S. P., Prepartion of modified ZnO nanoparticles by sol -gel process and their characterization, Master of Technology, 2009, Thapar university, Punjab.
[19]  Sreetama D. and Bichitra N. G.; Charaterization of ZnO nanoparticles grown in presence of Folic acid template, Journal of nanobiotechnology, 2012, vol. (10), pp. 29-34.
[20]  Khorsand A. Z., Razali R., Majid W. H.; Synthesis and characterization of narrow size distribution of zinc oxide nanoparticles, International journal of nanomedicine, Vol. 6, 2011, pp. 1399-1403.
[21]  Boundifa A., Zhang C. and Lahem M.; Highly sensetive and rapid NO2 gas sensors based on ZnO nanostructures and the morphology effect on their sensing performances, the 14th international meeting on chemical sensor (IMCS) 2012.
[22]  Haung X. H, Guo R. Q. and WuI. B.; Mesoporous ZnO nanosheets for lithium ionbatries, Materials Letters, Volume 122, 2014, pp 82-85.
[23]  Surye p.G.; Synthesis and characterization of zinc oxide nanoparticles by sol-gel process, Master of science in physics, National instituete of technology Rourkela, Orissa, India, 1-36(2012).
[24]  Hua Li, Jain C.D. and HuiR. D.; Synthesis and Characterization of chitosan ZnO nanoparticles composite membranes, carbohydrate research, Vol. 345, No. 8,2010, pp. 994-998.
[25]  Jeeju, p.p., Optical properties of highly transparent, thermally stable, spin coated zinc oxide (zno)/polystyrene (ps) nano composite films, Ph.D. thesis, Cohin university of science and technology, India, Chapter 3,2012.
[26]  Mahboubeh Mirhosseini and Fatemeh Firouzabadi, Preparation of zno-polystyrene composite films and investigation of antibacterial properties of zno/polystyrene composite films, Iranian journal of pathology 2014,(2), 99-16.
[27]  Chen C. Y., Chiang CL, Preparation of cotton fibers with antibacterial silver nano particles, Matter Lett. (2008), 62 (21-22-3607-3609).
[28]  Christopher Krapu "Synthesis and characterization of zinc-oxide/polystyrene nano composite thin films". Maca lester journal of physics and astronaut. Vol. 1, iss. 1 Article 7(2013).
[29]  Kaushik R. and sherma Nk, Current view on biomedical applications of synthesis metal-polymer nano composites, Janaki medical college journal of medical science (JMXJMS) (2014), vol. 2 (1); 52-58.
[30]  Dong Wook Chae and Boyoung Chul Kim, "Characterization on polystyrene/ zinc oxide nano composite prepared from solution mixing" polymers for advanced technology, division of applied chemical and bio-engineering, hanyang university, haengdang, seong dong, seoul pp, 133-191, 2005.
[31]  Shuang Xu, Yang jiao and Chang hang, Preparation and characterization of novel nano-ZnO/polystyrene resin composites advanced materials research vol. (496) (2012), 220-223.
[32]  Liu., J. J., Yu. M. H., and Zhou, W. L. Apply. Phys. lett. 2005, Vol. 87, 172505.
[33]  Wu B.J. And Liu, S. C.; low –Temperature growth of well – aligned ZnO nanorods by chemical vapor deposition. Advanced materials 14; 215 -218(2002).
[34]  Wu H., and W. J. Amer. Ceram. Soc. 2006, 89(2) 699.
[35]  Yang Y., Li X. and Bao X. ZnO nanoparticles prepared by thermal decomposition of b-cyclodextrincoated zinc acetate, Chemical physics letters 373. 22-279(2003).
[36]  Qin X. and Wang S. Journal of applied polymer science 2006, 102, 1285.
[37]  Toronto P. Phatanasri S. and Praserthdam P.; preparation of ZnO nanorods by solovthermal reaction of zinc acetate in various alchohols. Ceramics International 34: 57-62(2008).
[38]  G. Nina, A. Bruno, T. Fasolving and C. minority, Optical properties of polystyrene-light extraction in organic light-emitting diode, Journal of Nano materials, Volume (5), 2(2012).
[39]  Md Azad Alam, sajjad arif and mohd shariq, Enhancement in mechanical properties of polystyrene ZnO nanocomposites, International journal of innovative research in advanced engineering (IJIRAE), vol. 2(5) (2015), pp.122-129.
[40]  K. Balachandra Kumar and P.Raj, Synthesis and characterization of nano zinc oxide by sol gel spin coating, recent research in science and technology, 2011, 3(3); 48-52.
[41]  Md Azad Alam, sajjad arif and mohd shariq, Enhancement in mechanical properties of polystyrene ZnO nanocomposite, International journal of innovation research in advanced engineering, issue 6, Vol. 2 (2015), pp.122-129.
[42]  Alexandre M. and Dubios P., "Polymer layered silicate nano composite preparation, properties and uses of new class material" Materials science and engineering, Vol. 28, 1-63,2000.
[43]  Alam M.A., Arif S. and Ansati A.H., "Effect of nano ZnO on the mechanical behavior of polystyrene matrix composites", International conference on advances in design and manufacturing (ICAD and M14), 335-361(2015).
[44]  Arif S., Alam M.A. and Ansati A.H., "Effect of stirring speed and filler concentration on hardness of PMMAICaCO3 nano composites through Taguchi's analysis", International journal of innovative research in science, engineering and technology, vol.4, issue 6, 2015.
[45]  Riyadh M. Alwan, Quraish A. Kadhim and Alwan N. Jassim; Synthesis of zinc oxide nano-particles via so-gel route and their characterization, Nano science and nanotechnology 2015, 5(1); 1-6.
[46]  Sunil Bajpai, Navin Chand and Ruchi Lone, Water sorption properties and antimicrobial action on zinc oxide nanoparticles loaded sago starch film, Journal of microbiology, biotechnology and food science (2013): 2(4) 2368-2387.
[47]  Yang, P.D., Yan, H.Q. and Russo, R., Controlled growth of ZnO nano wires and their optical properties, advanced functional material, vol. 12, 2002, p.323-331.
[48]  R. I. Zheng and Guoxiang Cheng; Fabrication of zinc oxide/polystyrene grafted nano composite, European polymer journals, Vol. 43 issue 10 9(2007), pp. 4210-4218.
[49]  Yao Tu, Li Zhou, Chao Gao and Oing Ling; Transparent and flexible thin films of ZnO/polystyrene nano composite for UV-shielding applications, Journal of material chemistry, 2010, Vol. 20 p. 1594-1599.