The Improvement Of The Mechanical Properties Of PMMA Denture Base By A1_2O_3 Particles With Nitrile Rubber

摘要

Poly methyl methacrylate (PMMA) is mostly used for fabrication of denture base by heat-curing technique. Therefore, the purpose of this study is to investigate the effect of A12O3 filler as toughening particles together with nitrile butadiene rubber (NBR) particles as impact modifier were used to reinforce PMMA denture base materials on the impact strength (IS) and fracture toughness (K_Ic). PMMA powder was mixed with liquid methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDMA) as crosslinking agent. The powder components are PMMA, benzoyl peroxide, NBR (5, 7.5 and 10 wt%), and A12O3 filler (5 wt%) treated by silane. The liquid components are 90% of methyl methacrylate and 10 % ethylene glycol dimethacryate. FTTR analyses confirmed that the AI2O3 filler was successfully treated with silane as coupling agent. The morphology of fracture surfaces was characterized using field emission scanning electron microscopy (FESEM). The results shown that IS and K_Ic improved significantly when using treated the A12O3 filler. IS has increased to 56% (8.26 KJ/m~2) and 73% (2.77 MPa.m~(1/2)) for K_Ic when treated Al_2O3 filler compared to unreinforced PMMA matrix. Statistical analyses of data results were significantly improved (P<0.05) when using 7.5 wt% NBR with treated Al2O3 filler compared to other the compositions.