الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
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Abstract
The objective of this study is to take advantage of and so minimize the waste generated from the marble and granite industry in order to minimize its highly negative impacts on the environment. This is carried out by compounding marble and granite dust with polystyrene polymer and specifically high impact polystyrene which is a grade of polystyrene modified with polybutadiene micro-particles. The formed filler composite was then subjected to different mechanical and physical tests and the results were analyzed and interpreted in a way to reveal the ability of marble and granite dust to be used as filler in polymeric composites. In addition, marble and granite dust filler particles were surface modified using stearic acid for the aim of enhancing the final composite properties. Once again, the formed filler composites but this time with the fillers having their surface modified, were mechanically and physically tested and the results were analyzed and discussed.
Chapter 1 starts with discussing the nature of rocks and specifically marble and granite rocks and how they contribute in the generation of large amounts of industrial wastes. Marble and granite quarrying, slab cutting and the final polishing stages are briefly reviewed, mentioning the types and amounts of waste generated throughout as well as their impacts on human health and the environment. The polymeric matrix used in the study was high impact polystyrene as mentioned above, a grade of polystyrene which is a commodity thermoplastic polymer with very wide use and relatively low cost. The structure of polystyrene, its general properties, types, grades and the polymerization process at which it undergoes were identified and discussed, with some extra focus on the high impact polystyrene grade. Next, the filler surface modifiers were classified and the different methods for coating the filler were mentioned and briefly explained. Stearic acid, the surface modifier used in this study for marble and granite dust filler particles was reviewed. Its structure, general properties and its effects on the filler surface was discussed in detail. Finally, if the fabricated polymeric composite is exposed to sunlight, it would undergo photodegradation. The process was reviewed and the effect of UV radiation which is the degrading band of the electromagnetic spectrum that reaches the earth surface was discussed. Its effect on polymers and polystyrene in specific in addition to high impact polystyrene was explored.
Chapter 2 presents the experimental work carried out in the study. Starting by how the used materials were acquired and prepared and how they were conditioned for the composite fabrication. Citations of the standard tests and formulas used throughout the study were made, as well as any additional used techniques, which was also interpreted in detail. The percentage of marble and granite dust was varied to study the effect of its presence as filler inside high impact polystyrene matrix. The marble and granite dust percentages used were 10, 20, 30, 40, 50 and 60 wt. %. Furthermore, the dust surface was chemically treated by adding 2 wt. % stearic acid in an attempt to prevent agglomerations of the filler particles. Tests were conducted to investigate the effect of marble and granite dust on the mechanical and physical properties of the polymeric composite. As for mechanical testing, three point bending test, charpy impact test and hardness test were conducted. The physical properties of the composite was evaluated through density, water absorption, UV exposure and erosion tests. SEM analysis was also performed as a way to reveal and interpret the results achieved throughout different tests.
The information and data collected from different tests and analysis were used to evaluate the mechanical and physical properties of the polymeric composite. This is represented in chapter 3, where results are reviewed and discussed.