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This research studied the effect of nano silica particles on wear behavior test , ultimate tensile strength ,impact strength, fracture toughness and hardness shore D of specimens composite material. The hand-lay-up method is used to preparation of specimens established from unsaturated polyester resin matrix reinforcement with 4% weight fraction glass fiber (chopped / woven) mat and 1%, 3%, 5% weight fraction of nano silica particle. The nano silica particles used in this study has an average size of (less than 45nm). The results showed that the specimen (up+4% woven glass fiber+5% nano SiO2) gives better mechanical properties include ultimate tensile strength, impact strength, fracture toughness and hardness shore D (110 MPa, 13.7 K.J/m 2 , 18.92 MPa.m 1/2 , 85 shore D) respectively,when compare other specimens. The wear rate decreased from (22.5×10-4 cm 3 /N.m) for specimen (pure unsaturated polyester resin) to (0.18×10-4 cm 3 /N.m) for specimen (UP+4% woven glass fiber +5% nano SiO2) under parameter 7N (load), 15 minutes (sliding time), 2m/s (sliding speed) and (7 cm) sliding distance.

In this study, the main objective is to develop a good chelation and ion exchange hydrogel. This hydrogel is obtained by polymerization of dimethyl amino ethyl methacrylate (DMAEMA) and acrylic acid (AAc) by gamma irradiation, for the purpose of separation of some heavy and toxic metals from water. UV spectroscopy is applied to determine the metal ion concentration before and after treatment. The FTIR spectral analysis has identified the bond structure of PAAc, DMAEMA and P (DMAEMA/AAc) hydrogels. Microstructure and nanostructure are investigated by means of SEM and positron annihilation lifetime spectroscopy (PALS) respectively. A maximum swelling percent is found for 80/20 DMAEMA/AAc at free-volume hole size and fraction of 97 Ǻ 3 and 3.4% respectively. The P (DMAEMA/AAc) and PAAc hydrogels have been applied for Cu +2 , Co +2 and Ni +2 removals from aqueous solutions, and the factors affecting the adsorption capacity are determined. The adsorption capacity of P (DMAEMA/AAc) is found to be higher than the corresponding ones PAAc. Its experimental results showed that, the maximum adsorption of P (DMAEMA/AAc) after 24 h occurs at pH 7 with concentration of 250 ppm for Ni +2 ions and at pH 5 with concentration of 40 ppm for Cu +2 and Co +2 ions. The adsorption affinity of P (DMAEMA/AAc) hydrogel at different treatment contact times is in the following order Ni > Cu > Co. However, the order becomes Co > Ni > Cu by the variation of the pH of the metal ion solution; the variation of its concentration leads to a different order of Cu > Co > Ni.