Synthesis and characterization of polystyrene/magnesium hydroxide nanocomposites

A considerable attention has been focused on the Polymer matrix nanocomposites both academically and industrially. Impact resistance, modular, flame resistance, thermal stability and mechanical properties exhibit improvements when compared to the pure polymer. In this study magnesium hydroxide (Mg(OH)2) nanoparticles that used as inorganic material has been well distributed on organic polystyrene (PS) that used as matrix of the nanocomposite and the results were a new material having excellent properties. The distribution process has been provided by two different methods and using three different operating conditions of synthesis. Comparing between these two different methods and conditions, the PS properties especially flame resistance development and PS/Mg(OH)2 nanocomposites material characterization has been targeted in this study. The experiment contains the pre-preparation and synthesis levels as planned, in the pre-preparation level Benzoil Peroxide (BPO) used as a precursor, to remove the impurities and moisture the crystallization process has applied on the precursor. The hydrophilic property of the Mg(OH)2 construction makes it hard to distribute within polymer material, therefore it was modified to the lipophilic construction by using Oleic Acid (OA). Composite synthesis carried out by two process, first in toluene environment, styrene monomer and using various ratio of Mg(OH)2 obtaining PS/Mg(OH)2 nanocomposite material by using in-stiu method, and the second process was using PS that acquired from styrene solution polymerization process and various ratio of Mg(OH)2 to synthesis PS/Mg(OH)2 nanocompsite by using melt intercalation method. Due to the exothermic character of radical participation polymerization production of PS, self tuning PID temperature control method was used to keep the increase of temperature, however, the experiments has carried out at constant temperature. The composite materials prepared by both methods, was analyzed by the structural characteristics of transmission electron microscopy (TEM), thermal properties thermo gravimetric analysis (TGA), the flame retardancy (LOI) and mechanical characterization properties using Shore D hardness method. Also on the obtained PS, average viscosity and molecular weight values according to % monomer conversion has calculated. PS/Mg(OH)2 nanocomposites synthesis by using both melt intercalation and in-situ method was successfully completed. According to results that given by FTIR after the modification process that applied on Mg(OH)2 its appear that oleic acid has been chemically binding on the surface of the Mg(OH)2. TEM images shows that Mg(OH)2 nano particles in two methods distributed homogenously within PS. TGA results shows the increases of the Mg(OH)2 nano particles increases the temperature of the degradation start and end , therefore the Mg(OH)2 has a positive effect on the thermal stability of the PS. LOI values shows the nano particles of Mg(OH)2 has affected the positively to the flame resistance properties of the PS.