Journal of Advanced Materials in Engineering (Esteghlal)

In this study, NBG was successfully achieved through a sol-gel technique, and to further improve its dispersibility, a crylate coupling agent was coupled onto the surface of the NBG. The 3-(Trimethoxysilyl)Propylmethacrylate coupling agent was used to the surface modification of the synthesized NBG by a wet-chemical method in a dynamic inert nitrogen atmosphere. The surface properties of the biomaterials before and after modification were characterized and compared using FTIR and AFM techniques. The characteristic peaks in FTIR spectra indicated that –CH2, –CH3 and C=O groups appeared on the surface of modified NBG, and also, AFM analysis revealed that the dispersibility of surface modified NBG was improved, significantly. The above results proved that the desired groups of 3-(Trimethoxysilyl)Propyl methacrylate had been covalently bonded onto the surface of NBG. Besides, a nanocomposite scaffold was synthesized using the synthesized NBG and polyurethane foam as raw materials. The morphology of pores, porosity contents, compress strength and bioactivity of the scaffold were studied. The results showed that the biological scaffolds for use in bone tissue engineering with the basic requirements (90% porosity and 200-600 μm pore diameter) were successfully prepared. The polymer component had no effect on the relationship between the scaffold pores and bioactivity of bioglass nanoparticles. Improvement of compressive strength and proper bioactivity of the resulted scaffold showed that it is an acceptable candidate for biomaterials applications.

The aim of the present study is to study the effects of adding  diopside (CaMgSi₂O₆) as well as silica sulfuric acid nanoparticles to ceramic part of glass ionomer cement (GIC) in order to improve its mechanical properties. To do this, firstly, diopside (DIO) nanoparticles with chemical formula of CaMgSi₂O₆ were synthesized using sol-gel process and then, the structural and morphological properties of synthesized diopside nanoparticles were investigated. The results of scanning electron microscopy (SEM) and particle size analyzing (PSA) confirmed that synthesized diopside are nanoparticles and agglomerated. Besides, the result of X-ray diffraction (XRD) analyses approved the purity of diopside nanoparticles compounds. Silica sulfuric acid (SSA) nanoparticles are also prepared by chemical modification of silica nanoparticles by means of chlorosulfonic acid. Fourier transform infrared spectroscopy (FTIR) technique was used to find about the presence of the (SO₃H) groups on the surface of silica sulfuric acid nanoparticles. Furthermore, various amounts (0.1, 3 and 5 wt.%) of diopside and silica sulfuric acid nanoparticles were added to the ceramic part of GIC (Fuji II GIC commercial type) to produce glass ionomer cement nanocomposites. The mechanical properties of the produced nanocomposites were measured using the compressive strength, three-point flexural strength and diametral tensile strength methods. Fourier transform infrared spectroscopy technique confirmed the presence of the (SO₃H) groups on the surface of silica nanoparticles. The compressive strength, three-point flexural strength and diametral tensile strength were 42.5, 15.4 and 6 MPa, respectively, without addition. Although adding 1% silica solfonic acid improved nanocomposite mchanical properties by almost 122%, but maximum increase in nanocomposite mechanical properties was observed in the nanocomposites with 3% diposid, in which 160% increase was seen in the mechanical properties.