Optimization of Mechanical Properties for Polyoxymethylene/Glass Fiber/Polytetrafluoroethylene Composites Using Response Surface Methodology

Jasbir Singh Kunnan Singh; Yern Chee Ching; Luqman Chuah Abdullah; Kuan Yong Ching; Shaifulazuar Razali; Seng Neon Gan

doi:10.3390/polym10030338

Optimization of Mechanical Properties for Polyoxymethylene/Glass Fiber/Polytetrafluoroethylene Composites Using Response Surface Methodology

Polymers (Basel). 2018 Mar 20;10(3):338. doi: 10.3390/polym10030338.

Authors

Jasbir Singh Kunnan Singh^{1

2}, Yern Chee Ching^{3

4}, Luqman Chuah Abdullah⁵, Kuan Yong Ching⁶, Shaifulazuar Razali⁷, Seng Neon Gan⁸

Affiliations

¹ Department of Chemical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur 50603, Malaysia. jasbi@siswa.um.edu.my.
² Department of Mechanical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur 50603, Malaysia. jasbi@siswa.um.edu.my.
³ Department of Chemical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur 50603, Malaysia. chingyc@um.edu.my.
⁴ Department of Mechanical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur 50603, Malaysia. chingyc@um.edu.my.
⁵ Department of Chemical Engineering, Faculty of Engineering, University Putra Malaysia, Serdang 43400, Malaysia. chuah@upm.edu.my.
⁶ School of Foundation, University of Reading Malaysia, Persiaran Graduan, Kota Ilmu, Educity, Iskandar Puteri Johor 79200, Malaysia. kuanyong84@hotmail.com.
⁷ Department of Mechanical Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur 50603, Malaysia. shaiful@um.edu.my.
⁸ Department of Chemistry, Faculty of Science, University Malaya, Kuala Lumpur 50603, Malaysia. gansn@yahoo.com.

Abstract

This paper investigated the effects of polytetrafluoroethylene (PTFE) micro-particles on mechanical properties of polyoxymethylene (POM) composites. Since PTFE is immiscible with most polymers, the surface was etched using sodium naphthalene salt in tetrahydrofuran to increase its surface energy. The effects of two variables, namely PTFE content and PTFE etch time, on the mechanical properties of the composite were studied. Experiments were designed in accordance to response surface methodology (RSM) using central composite design (CCD). Samples were prepared with different compositions of PTFE (1.7, 4.0, 9.5, 15.0, or 17.3 wt %) at different PTFE etch times (2.9, 5.0, 10.0, 15.0, or 17.1 min). Four mechanical properties of the POM/GF/PTFE composites, that is, strength, stiffness, toughness, and hardness, were characterized as a function of two studied variables. The dependency of these mechanical properties on the PTFE etch conditions was analyzed using analysis of variance (ANOVA). Overall desirability, D global index, was computed based on the combination of these mechanical properties for POM/GF/PTFE composites. The D global index was found to be 87.5%, when PTFE content and PTFE etch time were 6.5% and 10 min, respectively. Good correlation between experimental and RSM models was obtained using normal probability plots.

Keywords: RSM; optimization; polyoxymethylene; polytetrafluoroethylene; surface etch.