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Enhancing Ballistic Impact Resistance of Polymer Matrix Composite Armors by Addition of Micro and Nano-Fillers

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Enhancing Ballistic Impact Resistance of Polymer Matrix Composite Armors by Addition of Micro and Nano-Fillers ENHANCING BALLISTIC IMPACT RESISTANCE OF POLYMER MATRIX COMPOSITE ARMORS BY ADDITION OF MICRO AND NANO-FILLERS A Thesis Submitted to the College of Graduate and Postdoctoral Studies In Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy In the Division of Biomedical Engineering University of Saskatchewan Saskatoon By Edison E. Haro © Copyright Edison Haro, July 2018. All rights reserved. Permission to use In presenting this thesis in partial fulfillment of the requirements for a postgraduate degree from the University of Saskatchewan, I agree that the Libraries of this University may make it freely available for inspection. I further agree that permission for copying of this thesis in any manner, in whole or in part, for scholarly purpose may be granted by the professors who supervised my thesis work or, in their absence, by the Head of the Department or the Dean of the College in which my thesis work was done. It is understood that any copying or publication or use of this thesis or part thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of Saskatchewan in any scholarly use which may be made of any material in my thesis. Requests for permission to copy or to make other use of material in this thesis in whole or part should be addressed to: College of Graduate and Postdoctoral Studies 116 Thorvaldson Building, 110 Science Place University of Saskatchewan Saskatoon, Saskatchewan (S7N 5C9) Canada OR Division of Biomedical Engineering Room 2B60 57 Campus Drive University of Saskatchewan Saskatoon, Saskatchewan (S7N 5A9) Canada i Abstract Improving the ballistic impact resistance of hybrid polymer matrix composites through addition of micro- and nano-particles as fillers is the principal goal of this research. Development of light- weight ballistic plates, made of polymer matrix composites with improved ballistic resistance, can offer a solution of shielding with lighter, thinner, stronger and less expensive materials than the conventional ballistic plates. The use of micro- and nano-particles in low concentrations can achieve this goal without compromising the density or strength of the new armor plates. Firstly, laminated hybrid composites consisting of aluminum alloy plates, epoxy resin and Kevlar® fabrics were developed. Shear thickening fluid (STF) made of nano-particles of colloidal silica (SiO2) was impregnated into Kevlar® fabrics to determine its effect on the energy absorption behavior of the composites. STF decreased the tendency of Kevlar® fibers to rupture during projectile penetration, and thus, increased its impact energy absorption performance when compared to the samples made of Kevlar® neat fabrics (containing no STF). Similar laminated hybrid composites were subsequently built through impregnation of micro- and nano-particles of aluminum, gamma alumina, silicon carbide, colloidal silica and potato flour into Kevlar fabrics by mixing these particles with polyethylene glycol. The obtained laminates were evaluated to determine their impact resistance and energy absorption capabilities under ballistic impact. The plates containing aluminum and colloidal silica nano-powders have the highest energy absorption capability of between 679 up to 693 J for plate thickness and areal density of about 10.8 mm and 1.9 g/cm2, respectively. These laminates can meet the protective requirements for levels IIA, II, and IIIA to resist ballistic impact from pistols caliber 9 mm. In another approach, hybrid composite armor plates based on high density polyethylene (HDPE) were prepared by using 10 wt.% of Kevlar® short fibers, and 20 wt.% chonta palm wood, potato flour, colloidal silica or gamma alumina particles. Addition of colloidal silica and gamma alumina nano-particles improve stiffness by 43.5% and increase impact energy absorption capability by 20%, compared to control sample, which is HDPE containing 10 wt.% Kevlar® short fibers. Hybrid bio-composites made of 10 wt.% Kevlar® short fibers and varying amount of chonta wood particles (10, 20, 30 wt. %), as additional reinforcement, were also developed and investigated. The hybrid composite plates containing 10 wt.% chonta palm wood micro-particles exhibited the ii highest energy absorption capability of 62.4 J, which is equivalent to 19.5 % improvement over control specimens: HDPE reinforced with 10 wt.% Kevlar® short fibers. Finally, bio-composites made of HDPE reinforced with varying fractions of micro-particles of chonta palm wood (10, 20, 25, and 30 wt. %) were developed and characterized. The ballistic impact performance of the biocomposites containing 25 wt.% chonta palm wood particles exhibited the highest energy absorption of 53.4 J, which represents a 41.3% improvement over the unreinforced HDPE specimens with similar thickness and density. iii Acknowledgement I would like to sincerely appreciate my supervisors Prof. Jerzy Szpunar and Prof. Akindele Odeshi for their guidance and endless support while carrying out this research project and in the course of writing this thesis. I wish to express my gratitude for their insights and comments that helped me to develop my research skills. I feel very fortunate for their unconditional support, I will always appreciate all they have done for me. I also would like to thank my advisory committee members: Prof. Ike Oguocha, Prof. Duncan Cree, and Prof. Lope Tabil for their encouragements and their very constructive comments and discussions. Additionally, I appreciate the valuable discussions and support from my friends and colleagues Xu Wen, A.A Tiamiyu and all members of the Advanced Materials and Renewable Energy (AMRE) group of the University of Saskatchewan. Finally, I acknowledge the financial support of the Natural Science and Engineering Research Council of Canada (NSERC), the National Secretary of Science and Technology of the Ecuador (SENESCYT), and Ecuadorian Army. iv Dedication I want to dedicate this thesis to my lovely family, Vanessa, Ian and Erika, for their unconditional support, especially when the tasks many times seemed overwhelming, you have always been my inspiration to be strong and persistent, no matter how great the obstacles have been. Also, to my beloved parents, the reason for what I become today and the achievements that I have accomplished. Thanks for your unconditional love and guide in all my challenges. v Table of Contents Permission to use ....................................................................................................................... i Abstract…… ............................................................................................................................ ii Acknowledgement ................................................................................................................... iv Dedication… ..............................................................................................................................v Table of Contents .................................................................................................................... vi List of Tables ........................................................................................................................... xi List of Figures......................................................................................................................... xii Acronyms.… ............................................................................................................................ xv Chapter 1 : Introduction ...........................................................................................................1 1.1 Overview ...........................................................................................................................1 1.2 Motivations for Research ...................................................................................................1 1.3 Research Objectives ..........................................................................................................2 1.4 Thesis Overview ................................................................................................................3 Chapter 2 : Literature Review ..................................................................................................5 2.1 Overview ...........................................................................................................................5 2.2 Body armor classifications and level of protection .............................................................5 2.3 Advanced composite materials used in ballistic armor applications ....................................7 2.4 Polymer matrix composites designed for ballistic protection ..............................................9 2.4.1 Hybrid composite armors based on polymer matrix composites ................................ 13 2.4.1.1 Hybrid matrix laminates ..................................................................................... 15 2.4.1.2 Natural fiber reinforced hybrid polymer composites ........................................... 17 2.4.2 Impregnation of micro- and nano-fillers in hybrid composite armors ........................ 18 2.5 Information gaps identified from literature review ........................................................... 19 Chapter 3 : Materials and Methods ....................................................................................... 21 vi 3.1 Overview ........................................................................................................................
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