Carboxylated Magnetite Composite Polymer Nanoparticles with Mosaic Structure for Biomedical Application
Pages 127-133
Kesavarao Sykam and Shailaja Donempudi

DOI: http://dx.doi.org/10.6000/1929-5995.2015.04.02.5

Published: 28 July 2015

Abstract: In this article, a microemulsion method for preparation of magnetite composite polymer nanoparticles of Fe₃O₄@poly(styrene-methacrylic acid) (MNP@PSMA) crosslinked with1,6-hexanediol diacrylate (HDD) insitu with carboxyl functionality on the surface has been reported. Structure and morphology of the nanoparticles was studied by Fourier Transform Infrared spctroscopy (FTIR), X ray Diffraction (XRD), Thermal Gravimetric Analyser (TGA), Vibrating Sample Magnetometer (VSM) and Transmission Electron Microscopy (TEM). VSM studies confirmed saturation magnetization of 20.0 emu/g in an external magnetic field. Nanoparticles formed were of 30 nm in diameter with narrow size distribution and mosaic structure providing a large surface area useful for application in bioseparation. Experimental results of covalent coupling of composite nanoparticles indicated maximum protein binding capacity of 350 mg bovine serum albumin (BSA) per gram.

A Brief Overview on Ferrite (Fe₃O₄) Based Polymeric Nanocomposites: Recent Developments and Challenges
Pages 184-204
O.P. Bajpai, D.K. Setua and S. Chattopadhyay

DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.04.1

Published: 02 January 2015

Abstract: In this article, we have mainly discussed about ferrite (Fe₃O₄)and its polymer based nanocomposites. Ferrite particles have become an important research material because of their vast applications in the field of biotechnology, magnetic resonance imaging (MRI), and data storage.It has been observed that ferrite Fe₃O₄particles show best performance for size less than 10-30 nm. This happens due to the super paramagnetic nature of such particles. In super paramagnetic range these particles exhibit zero remanence or coercivity. Therefore, various properties of ferrite (Fe₃O₄) nanoparticlesand its polymer nanocomposites are very much dependent on the size, and distribution of the particles in the polymeric matrix. Moreover, it has been also observed that the shape of the nanocrystals plays important role in the determination of their fundamental properties. These particles show instability over longer times due to the formation of agglomerates generated by high surface energies. Therefore, protection strategies such as grafting and coatings with silica/carbon or polymers have been developed to stabilize them chemically. Recently, silylation technique is mainly used for the modification of nanoparticles. Experimentally, it has been observed that nanocomposites composed ofpolymer matrices and ferriteshowed substantial improvements in stiffness, fracture toughness, sensing ability (magnetic as well as electric), impact energy absorption,and electro-catalytic activities to bio-species.

Characterization of Phosphate Glass Reinforced Gelatin Blend Bioactive Composite Films
Pages 149-156
Kamol Dey, Poonam Alamgir, Shahnaz Parvin, Gulshana Mohol,Wafa Tonny, Mubarak A. Khan and Ruhul A. Khan

DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.03.2

Published: 20 October 2014

Abstract: Bioactive composite films were prepared using bioresorbable phosphate glass powder and biodegradable polymer gelatin (G) through solution casting process. Biocompatible monomer, 2-hydroxyethyl methacrylate (HEMA) was used as the cross-linking agent and bioresorbable phosphate glass (PG) powder was used as reinforcement filler. The composite films were obtained at various ratios of G, PG and HEMA. The PG modified gelatin composite (PG/G) film was fabricated at a weight ratio of 12:88 while HEMA modified gelatin composite (HEMA/G) film at 50:50 ratio. On the other hand, hybrid gelatin composite film, containing both PG and HEMA, was obtained using a G/PG/HEMA ratio of 44:12:44. Incorporation of PG improved the mechanical properties of the composite films. Morphological property of the composite films was investigated by stereo microscope and it revealed that the composite films were porous in nature. The thermal behaviour of the films was studied using thermogravimetric analysis. Water uptake of the films was also performed.

Delamination and Separation of Aluminum-Polyethylene-Paper Packing Material
Pages 136-141
Chongqing Wang, Qun Liu, Hui Wang, Chengcheng Luo, Fangfang Jia and Xiangrui Meng

DOI: http://dx.doi.org/10.6000:1929-5995.2014.03.02.8

Published: 07 July 2014

Abstract: Delamination and separation of laminated aluminum- polyethylene-paper packaging material were conducted for recycling packaging materials. Delamination was carried out using glacial acetic acid (GAA) solution. L₉ (3⁴) orthogonal experiments demonstrate that the most significant factor is GAA concentration followed by temperature and liquid/solid ratio. The delamination time decreased sharply with increasing temperature and the GAA concentration. The packaging material was delaminated under conditions of 60 ˚C, 70 v% GAA solution, liquid/solid ratio 20:1 and delamination time 60 min, and separation of polyethylene, paper and aluminum foil was conducted through sink-float method and air separation. Polyethylene, paper and aluminum foil were separated efficiently. The recovery and purity of aluminum foil was 90.81% and 100%, respectively; the purity of polyethylene was 100%; the recovery and purity of paper was 100% and 96.03%, respectively. This study offers some technical insights for recycling of aluminum-plastic packaging.

Innovative Rice Seed Coating (Oryza Sativa) with Polymer Nanofibres and Microparticles Using the Electrospinning Method
Pages 33-39
Letícia M.F. Castañeda, Cayane Genro, Isabel Roggia, Stefan S. Bender, Renar J. Bender and Cláudio N. Pereira

DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.01.5

Published: 02 April 2014

Abstract: Seed treatments are chemical or biological substances that are applied to seeds to control infection by disease-causing organisms, insects, or other pests. Seed treatment reduces production costs of seedlings, reduces the consumption of seeds, facilitates mechanization of sowing and improves the seedling establishment. The generation of nanofibres and microcapsules by the electrospinning technique is a novel approach for active ingredient controlled release. The study evaluates an innovative rice seed coating (Oryza sativa) with polymer nanofibres and microparticles using this method.

Materials and Methods:Polymer nanofibres and microcapsules were applied by the electrospinning technique to irrigated rice seeds. The treatments consisted of: 1) Control, 2) Negative control - Polymer based microcapsule without fungicide. 3) Polymer based microcapsule with fungicide. Microbiological assays and germination tests were performed following the guidelines of the Seed Analysis Rules of the Ministry of Agriculture.

Results:The applied polymer as a coating did not affect the physiological quality of the seeds, as attested by the result of the germination tests, and they proved to be effective in the control of fungi disease in crop seeds.

Conclusion: The germination and phytosanitary characteristics were improved in the analyzed study.