Nano composite
Shaghaiegh Rezanezhad; Noureddin Nazarnezhad; Hosein Resalati; Seyed Majid Zabihzadeh
Abstract
Background and objectives: Carboxy methyl cellulose (CMC) is one the ether derivatives of cellulose and is widely used in various industries. This material is one of the most important and widely used cellulose derivatives, which has been considered in many researches as a substrate for the production ...
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Background and objectives: Carboxy methyl cellulose (CMC) is one the ether derivatives of cellulose and is widely used in various industries. This material is one of the most important and widely used cellulose derivatives, which has been considered in many researches as a substrate for the production of composite materials due to the presence of the carboxy methyl and hydroxyl groups. CMC can also be used as a substrate for the production of the magnetic cellulose compounds. Magnetic materials such as iron oxide are able to form effective bonds with hydroxyl groups in CMC and produce magnetic composites with biodegradable properties. The purpose of this research is to produce and analyze the magnetic properties of biocomposite made from CMC and then coat it on the surface of paper.Methodology: In this research, CMC was used as a substrate for the production of magnetic biocomposite. The in-situ synthesis was used to produce biocomposite. In the process, iron salts (4 and 6 H2O) and CMC were mixed together in an aqueous solution and under nitrogen atmosphere, then by adding ammonium hydroxide to pH 11, iron oxide particles (magnetite) were formed on CMC. The materials were stirred in water bath for 1 hour at 40 °C, in order to complete the reactions and increase the production efficiency of magnetic particles. Handsheets with 120 ± 5 g/m2 weight was prepared by using commercial kraft fibers, and then coated with magnetic biocomposite. The synthesized magnetic materials and coated paper with magnetic biocomposite were analyzed by X-ray diffraction. The size of iron oxide was tested by an atomic force microscope. Also, the morphology and surface characteristics of magnetic particles, magnetic biocomposite and coated fibers and paper were investigated by scanning electron microscope. The magnetic properties of the samples were evaluated with a vibrating magnetometer. Furthermore, the strengths properties of the coated paper were examined with tensile, tear, water absorption and air resistance tests.Results: The results of the magnetic test showed that in the first phase, the magnetic biocomposite was successfully prepared and the sample showed super paramagnetic properties. The highest magnetic saturation in the iron oxide sample was about 25 emu/g. Also, the CMC magnetic biocomposite had a magnetic saturation about 4 emu/g. The results of the microscopic evaluation of the iron oxide particles showed a uniform cubic structure. The formation of this structure is due to the accumulation of particles. In addition, mechanical engagement and connection of the magnetic biocomposite with the paper was observed. Also, the microscopic analyze of the iron oxide showed the most frequent of particles size were 45 nm. The results of the strength properties of the paper showed that the coating with magnetic material decreased the tensile and tear indices. The air resistance in the coated paper samples has increased compared to the control sample. Based on the results of Cobb test (water absorption), the lowest water absorption is related to the coated paper with CMC magnetic biocomposite. The X-ray diffraction pattern of the iron oxide sample showed five important peaks at 2 theta angles of 35, 41, 50, 67 and 74 degrees, which the main peaks indicated the iron oxide.Conclusion: The purpose of this research was to analyze the magnetic property in the CMC biocomposite and then coat it on the surface of the paper. Therefore, the experiments were carried out in 2 stages. In the first stage, CMC magnetic biocomposite was made by in situ synthesis process with iron salts. In the second phase, handsheet was prepared by using commercial kraft fibers and coated ones. The results of the testing samples showed the successfully production of magnetic biocomposite. Also, the paper coated with this material has suitable magnetic properties.
Pulp and paper
Amir Hosein Ghasemi; Noureddin Nazarnezhad; Shaghaygh Rezanezhad; Seed Hasan Sharifi
Abstract
Background and objectives: Some medicinal herb extracts have the antibacterial capability. On the other hand, herb extract is one of the organic, natural, and environmentally friendly substances. In recent years, the production of environmental and safe packaging materials has attracted the attention ...
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Background and objectives: Some medicinal herb extracts have the antibacterial capability. On the other hand, herb extract is one of the organic, natural, and environmentally friendly substances. In recent years, the production of environmental and safe packaging materials has attracted the attention of scientists and industrialists. Paper is one of the biodegradable and less cost options for packaging in various industries, including the food industry. Also, the raw materials of paper can be modified and changed with different materials. As a result, paper fibers can be treated with herb extracts and used in the production of renewable papers with antibacterial properties.Methodology: In this research, thyme (Zataria Multiflora) was used for extraction. The thyme obtained from the research farm was dried and then powdered. Powdered thyme was treated via ultrasonication. In this method, two amplitudes of 40 and 60 amplitudes and three time levels of 3, 6, and 9 minutes were used for extraction. Then the papers were treated with herbal extract prepared in two amounts of 15 and 20% based on the dry weight of the paper by spraying. The antibacterial properties of the papers were investigated with Escherichia coli and Staphylococcus aureus bacteria. The chemical structure of materials extracted from the thyme extract investigated by fourier transform infrared spectrum (FTIR) analysis. Also, gas chromatography (GC-MASS) analysis was used to investigate the components of thyme extract. The optical properties of the paper, including brightness and opacity, and the strengths properties of the produced papers were measured by tensile, tear, and burst strengths.Results: The highest inhibition zone diameter in the treated paper with the thyme extracted by ultrasonic method was 20 mm in 40 amplitude and 9 minutes for Escherichia coli bacteria. Also, the highest inhibition zone diameter for Staphylococcus aureus bacteria was 14 mm in 60 amplitude and 6 minutes. According to the results of the papers analysis, the papers showed better antibacterial properties and higher inhibition zone against the Escherichia coli bacteria. The chemical compounds in the thyme extract including various substances such as hexane and furans. The most important chemical components that caused the antibacterial properties of the papers is carvenone, which was observed in the thyme extract. The results of the strength test of the treated papers showed that the sample of the thyme extracted by the ultrasonic method at 40 amplitudes, 3 minutes, and the 20% consumption amount based on the dry weight of the paper has the highest tensile and burst index. As well as, the highest tear index of the treated papers was in the treated sample with the thyme extracted at 60 amplitudes, 3 minutes, and 15% consumption amount based on the dry weight of the paper. The results of the optical tests showed that the opacity of the papers decreased and the brightness increased.Conclusion: The results of this research showed that the paper as a biodegradable and environmentally friendly material has the ability to be treated with herbal and natural antibacterial materials such as the thyme extract. Also, the herbal extracts are a suitable alternative to inorganic and metallic materials in the production of materials with antibacterial properties due to the herbal extracts are cheap, available and natural materials.
