MORPHOLOGICAL CHARACTERISATION OF POLY METHYL METHACRYLATE FOR SURFACE COATING OF METALS

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 6, Issue 8, Aug 2015, pp , Article ID: IJMET_06_08_013 Available online at ISSN Print: and ISSN Online: IAEME Publication MORPHOLOGICAL CHARACTERISATION OF POLY METHYL METHACRYLATE FOR SURFACE COATING OF METALS N. Jayakumar Ph.D research scholar, Department of Mechanical Engineering, AMET University, Chennai, India Dr. S. Mohanamurugan Professor and Head, Department of Automobile Engineering, Saveetha University, Chennai, India Dr. R. Rajavel Professor and Head, Department of Mechanical Engineering, AMET University, Chennai, India V. Srinivasan Assistant Professor, Department of Mechanical Engineering, Bharath University, Chennai, India ABSTRACT Poly methyl methacrylate (PMMA) is one of the most important industrial plastics. On the whole, characterization of PMMA refers to the general process by which its structure and properties are investigated and measured. It is a radical process, without which no scientific understanding of PMMA can be made certain. The scope of the term characterization of PMMA differs. Some researchers limit its use to modi operandi which study the microscopic configuration and chattels of PMMA which is called microscopy while others use it to refer to any analysis process including macroscopic techniques viz. mechanical testing, thermal study and density computation. Here, we are adopting both macroscopic techniques as well as microscopic techniques such as Fourier transform infrared spectroscopy (FTIR) and X-Ray diffraction (XRD) tests to characterize PMMA in order to verify whether the material is pure and amorphous in nature so that this material could be used subsequently for metal coating. Key words: Characterization, Poly methyl methacrylate, X-Ray diffraction and Fourier transform infrared spectroscopy editor@iaeme.com

2 N. Jayakumar, Dr. S. Mohanamurugan, Dr. R. Rajavel and V. Srinivasan Cite this Article: Jayakumar, N., Dr. Mohanamurugan, S., Dr. Rajavel, R. and Srinivasan, V. Morphological Characterisation of Poly Methyl Methacrylate for Surface Coating of Metals. International Journal of Mechanical Engineering and Technology, 6(8), 2015, pp INTRODUCTION The first step in characterization of PMMA is a macroscopic observation. It means, simply looking at the material with naked eye. This simple process could yield a large amount of information about the material such as the color of the resin, its luster, its shape ie whether it exhibits regular form or crystalline form, its composition ie is it made up of different phases?, its structural features ie does it contain porosity? etc. The next step is the microscopic observation that includes FTIR and XRD tests. Juan Li studied the chemical structure of the PMMA, PMMA-b-PDMAEMA and PMMA-b-PDMAEA polymers by FT-IR spectroscopy on a Nicolet 6700 FT-IR spectrophotometer (Thermo Inc., America) with the polymer samples dispersed in KBr pellets. The copolymer compositions were determined by NMR spectroscopy. HNMR measurements were performed on a UNITY-plus 400 M nuclear magnetic resonance spectrometer(varian, Inc., America) using CDCl as the solvent. XRD was used to test the crystalline of the polymers on X PERT PRO X-ray diffraction (PANalytical, Netherlands). [1] Shahzada Ahmad illustrated the diffractograms of PMMA and PMMA SiO2 composites in the 2θ range between 5 and 90 degree, which were similar and without any sharp diffraction peaks confirming their non-crystalline nature. The interlayer spacing of the system was determined by the diffraction peak in the X-ray method, using the Bragg equation λ = 2dsin θ, where d is the spacing between diffractional lattice planes, θ is the diffraction position while λ is the wavelength of the X-ray ( Å). PMMA is known to be an amorphous polymer and showed three broad peaks at 2θ values of 12, 30 and 32 (d spacing around 7 Å, 2 94 Å and 2 79 Å), with their intensity decreasing systematically. The shape of the first most intense peak reflects the ordered packing of polymer chains while the second peak denotes the ordering inside the main chains. The addition of SiO2 does not induce any crystallinity in these polymers. This also explains the homogeneous nature of these samples. He also depicted that the FT IR spectra of PMMA, PMMA SiO2 and PMMA TiO2were similar except for a few changes in the spectra of the nano composites. The features that were similar identified the presence of PMMA in all of them. [2] A.K.Tomar characterized the structure of PAni powder, pure PMMA and their blended films by using X-ray Diffraction (XRD) and Fourier Transform Infrared spectroscopic (FTIR) techniques. In his characterization, X-ray diffraction patterns of unblended PMMA and various PMMA-PAni blended films were presented and it was apparent that X-ray pattern of PMMA matrix could show broad bands peaking at around 2 = 15.45, and indicating its amorphous nature. The X-ray pattern of various PAni- PMMA blended films showed the absence of the peaks which were present in PAni with the broadening of peak of PMMA indicating the amorphous nature of PAni- PMMA blended films. The structure of pure PMMA was primarily characterized by the 1736 cm ¹ band assigned to free lateral C=O stretching in the FTIR study. [3] editor@iaeme.com

3 Morphological Characterisation of Poly Methyl Methacrylate for Surface Coating of Metals S. Sathish adopted FTIR and XRD analysis for characterizing a thin film of PMMA. In FTIR spectroscopy, the bands at about 677 cm - ¹ and 750 cm - ¹ were assigned to out of plane OH bending. The band at around 980 cm - ¹ was the characteristic absorption vibration of PMMA. The bands at about 1060 cm - ¹, 1245 cm - ¹, 1730 cm - ¹ and 2926 cm - ¹ were assigned to ν(c-o) stretching vibration, wagging vibration of C-H, C=O stretching and C-H stretching respectively. The relatively broad and intense absorption observed at around 3400 cm - ¹ indicated the presence of O-H stretching vibration. It was also found that both as grown and annealed films showed similar FTIR spectrum which eliminated the presence of any impurity in PMMA thin films. The X-ray diffraction indicated amorphous nature with large diffraction maximum that decreases at large diffraction angles. The observed broad humps in the XRD spectrum indicated the presence of crystallites of very low dimensions. The absence of any prominent peaks indicated the amorphous nature of the thin PMMA films. [4] Devikala experimented XRD, SEM and techniques to characterize PMMA- Zirconium dioxide composite. The XRD patterns of polymers and polymer composites were recorded using Philips X PERT PRO diffractometer with Cu Kα (λ= Å) incident radiation. The XRD pattern for PMMA showed peaks at 2θ is equal to 14.50, 22.49, and and relative intensities obtained for the polymer matched with the JCPDS Card no file, identifying it as PMMA. The average crystallite size of PMMA was determined using XPert High Score plus software and it was found to be μm. From XRD of composites, she could say that the crystallinity of PMMA had decreased considerably upon the addition of ZrO2. [5] The average crystallite size was found to be μm. [6] 2. EXPERIMENTAL DETAILS 2.1. Material White, crystalline PMMA powder with melting point > 150 C, molecular weight K and size mesh was obtained from Alfa Aesar (Product Number 43982) through H.Chandanmal & Co., Chennai, India Characterization To comprehend the properties of the polymer material, it becomes necessary to know the features of its structure. X-Ray Diffraction technique (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) technique were employed to characterize PMMA XRD Analysis X-ray diffraction is one of the most important characterization tools used in materials science to determine the size and the shape of the unit cell for any compound most easily. X-ray diffraction provides the most definitive structural information such as inter atomic distances and bond angles. Table 1 shows the measurement conditions for the XRD test conducted for the PMMA powder FTIR Test FTIR spectroscopy is the most preferred method of infrared spectroscopy. In this spectroscopy, infrared radiation was passed through the sample PMMA powder. Some of the infrared radiation was absorbed by the sample, some of it was reflected and some of it was transmitted. The resulting spectrum represented the molecular editor@iaeme.com

4 intensity (cps) N. Jayakumar, Dr. S. Mohanamurugan, Dr. R. Rajavel and V. Srinivasan absorption, reflection and transmission, creating a molecular fingerprint of the sample. Like a fingerprint no two unique molecular structures produce the same infrared spectrum. This infrared spectroscopy is also useful for several types of analysis such as identifying material, determining the quality or consistency of the sample and determining the amount of components in a sample. X-Ray Table 1 Measurement conditions for XRD test 30kV,100mA Scan speed/duration time deg/min Goniometer Smart Lab Step width deg Attachment Standard Scan axis Theta/2-Theta Filter Cu_K-beta Scan range deg CBO selection list BB Incident slit 2/3 deg Diffracted beam mono None Length limiting slit 10.0 mm Detector SC-70 Receiving slit # 1 2/3 deg Scan mode CONTINUOU S Receiving slit # mm 3. RESULTS AND DISCUSSION In order to collect information about the structure, XRD and FTIR spectra of PMMA powder were examined. The morphology of pure PMMA powder was studied by an XRD test. The X-ray diffraction pattern of PMMA is presented in Figure 1. From the figure, it is obvious that X-ray pattern of PMMA shows broad bands peaking at around 2 = 13.85, and The X-ray pattern, peaking around these angles indicates the amorphous nature of the PMMA powder theta (deg) Figure 1 XRD pattern of pure PMMA powder The FTIR spectra of pure PMMA powder are presented in Figure 2, with peaks at 1185 cm - ¹ (Transmission) 1756 cm - ¹ (Reflection) 1783 cm - ¹ (Absorbance). These peaks confirm the absence of any additional bands other than those of PMMA and further they remain unperturbed in all the three spectra which indicate the purity of the polymer tested editor@iaeme.com

5 Morphological Characterisation of Poly Methyl Methacrylate for Surface Coating of Metals %T 60 %R Abs Figure 2 FTIR spectra of PMMA powder for Transmission, Reflection and Absorbption 4. CONCLUSION The amorphous nature of PMMA was confirmed through the XRD test result. Due to the intertwining chains, amorphous polymers experience viscous flow when heated. They also have a decreased chance of warping and shrinking during molding, casting or coating than semi-crystalline plastics. The amorphous nature of PMMA may also exhibit rubber-like properties, able to stretch and deform without fracturing. All these features of PMMA make it one of the best materials for metal coating. The FTIR analysis showed that there are no impurities in the PMMA powder. Impurities in a virgin polymer ruin the possibilities of using the material for certain applications that include using it as a coating material. As the FTIR analysis showed the absence of impurities, it was ascertained that PMMA could subsequently be used to coat metal surfaces. 5. REFERENCES [1] Li, J., Jiang, T.-T., Shen, J.-N. and Ruan, H.-M. Preparation and Characterization of PMMA and its Derivative via RAFT Technique in the Presence of Disulfide as a Source of Chain Transfer Agent. Journal of Membrane and Separation Technology, 1(2), [2] Ahmad, S., Ahmad, S. and Agnihotry, S. A. Synthesis and characterization of in situ prepared poly (methyl methacrylate) nanocomposites. Bull. Mater. Sci., 30(1), February 2007, pp Indian Academy of Sciences. [3] Tomar, A. K., Mahendia, S. and Kumar, S. Structural characterization of PMMA blended with chemically synthesized PAni. Adv. Appl. Sci. Res., 2(3), 2011, pp [4] Sathish, S. and Chandar Shekar, B. Preparation and Characterization of nano scale thin PMMA films. Indian Journal of Pure and & Applied Physics, 52, January 2014, pp [5] Kuruvinashetti, M., Ismail, M. and Suresha, B. Morphological Two-Body Abrasive Wear Behavior of Short Glass Fiber and Particulate Filled Polymethyl Methacrylate Composites. International Journal of Mechanical Engineering and Technology, 5(9), 2014, pp [6] Devikala, S., Kamaraj, P. and Arthanareeswari, M. Preparation, Characterization and Anticorrosive Properties of a Novel PMMA/ ZrO₂ Composite. Indian Journal of Applied Research, 4(5), May 2014, ISSN X editor@iaeme.com