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Biopolymer Congress 2018: E-BABE- Fabrication and characterization of chitosan/montmorillonite/ZrO2 nanocomposite scaffold - Abbas Teimouri - Payame Noor University

Abbas Teimouri 

Biopolymers have the same privileges as biodegradable and similar structural groups for natural extra cellular components. Chitosan as a functional material suitable for biomedical applications because of its excellent properties such as bio-compatibility, antigenicity, biodegradability, antibacterial, blood coagulation, and high mechanical strength suitable for tissue engineering are considered. It is often combined with clays such as Na-montmorillonite to enhance the mechanical strength, good chemical, dimensional stability and hardness of the chitosan. Within this study, a highly specialized scaffold freeze-drying method consisting of chitosan (CTS), montmorillonite (MMT) and nano-zirconia (nano-SRO2) was prepared.              CTS / MMT / ZrO2 Montmorillonite for nanocomposite, And strengthened by zirconia. SEM, XRD and FT-IR studies were characteristic of these, demonstrating the formation of nanocomposite scaffolds. The thermal stability was shown using the TGA method, so the area, pore size, and hence the pore distribution of CTS / MMT / SRO2 were calculated using the BET technique. Montmorillonite may also be a mild phyllosilicate group of minerals that can be formed after dissolving into water-soluble microparticles called clay crystals. It is named after Montmorillon, France. The smectite A member of the group, Montmorillonite, may be a 2: 1 clay, that is, a central octahedral sheet of alumina, two tetrahedral sheets of silica sandwich. The particles are in the shape of a plate with a diameter around 0.9 nm and a thickness around 1 μm; To "see" individual clay particles, they need to be enlarged approximately 25,000 times with a microscope. Members of this group include saponite.Montmorillonite could even be a subclass of smectite, a 2: 1 phyllosilicate mineral characterized as having an octahedral charge greater than 50%; its cation exchange capacity is due to the isomorphic substitution of Mg for Al in the central plane of alumina. Substitution of lower valence cations in such cases leaves the oxygen atoms nearby with a net charge which can attract the cations. In contrast, beidellite is smectite with a tetrahedral charge greater than 50% from the isomorphic substitution of Al for Si in the silica sheet. The individual crystals of montmorillonite clay are not closely linked, so that water can intervene, causing the clay to swell. The water content of montmorillonite is variable and it increases considerably in volume when it absorbs water. Chemically, it is sodium silicate hydroxide-aluminum-magnesium hydrate (Na, Ca) 0.33 (Al, Mg) 2 (Si4O10) (OH) 2 · nH2O. Potassium, iron and other cations are common substitutes, so the precise ratio of cations varies depending on the source. It often occurs in admixture with chlorite, muscovite, illite, cookeite and kaolinite. Montmorillonite is used in the oil drilling industry as a lubricant component, which makes mud mud viscous, which helps keep the bit cool and removes drilled solids. it is also used as an additive to retain soil water in drought prone soils, used in the development of dams and earthen pits, and to prevent leakage of fluids. it is also used as a component of foundry sand and as a desiccant to induce humidity in air and gases. Montmorillonite clays are widely used in catalytic processes. Cracking catalysts have used montmorillonite clays for more than 60 years. Other acid-based catalysts use acid-treated montmorillonite clays. Montmorillonites are expanding considerably quite other clays because of water penetrating the interlayer molecular spaces and asaithe concurrent. the quantity of expansion is mainly due to the type of interchangeable cation in the sample. The presence of sodium because the clay swelling to its original volume may be repeatedly caused by the greatest interchangeable cation. Accordingly, sodium montmorillonite was used because it is the most important ingredient in non-component agents for splitting rock in natural stone quarries in an attempt to limit the amount of waste, or to demolish concrete structures where it is impossible to use removal of explosive charges. Because of this reconstructive property bentonite containing montmorillonite is also useful as a seal or annular additive for water wells and as a protective liner for landfills. Other uses include as an antidepressant agent in animal feed, in paper-making to reduce deposit formation, and as a maintenance and drainage assistance component. Montmorillonite was used in cosmetics. In fine powder form, it can also be used as a flocculant in ponds. It is thrown to the surface because it falls into the water, making the water "cloudy", attracts small particles within the water and settles on the lower one, cleansing the water. Koi and goldfish (carpet) then feed the "clump" which helps digest the fish. it is sold in pond supply stores. Sodium montmorillonite is also used due to the origin of some cat litter products, due to its adsorbent and clumping properties.