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Raw materials used in the glass of high borosilicate glass bottles

The glass raw materials of the high borosilicate glass bottle are: quartz sand (SiO2), borax (Na2B4O7·10H2O), boric acid (H3BO3), sodium nitrate (NaNO3), aluminum hydroxide (Al(OH)3), salt (NaCl), Sodium fluorosilicate (Na2SiF6), broken glass.

 ①Quartz sand: mainly introduce silicon dioxide (SiO2). Silica is an important glass-forming oxide. In the glass, the structural units of silicon-oxygen tetrahedron [SiO4] form an irregular continuous structure to form the framework of the glass. Silica can reduce the thermal expansion coefficient of glass and improve the thermal stability, chemical stability, softening temperature, heat resistance, hardness, mechanical strength, transparency and viscosity of glass.

② Borax: Na2O and B2O3 are introduced at the same time during melting, and B2O3 is volatile. B2O3 can reduce the thermal expansion coefficient of the glass, improve the thermal and chemical stability of the glass, improve the gloss of the glass, and increase the mechanical strength of the glass. B2O3 can reduce the viscosity of glass at high temperature, and increase the viscosity of glass at low temperature. B2O3 also plays a role of fluxing.

③ Boric acid: Decomposes into molten B2O3 when heated at high temperature. The role of B2O3 is as described in the above-mentioned borax.

④Aluminum hydroxide: Al2O3 is generated by decomposition at high temperature. Al2O3 in the glass can improve the chemical stability of the glass, increase the mechanical strength, and reduce the tendency of glass to crystallize. Al2O3 can also reduce the thermal expansion coefficient of glass, improve the thermal stability of glass, and reduce the corrosion of glass melt to refractory materials. However, the increase of Al2O3 content will greatly increase the viscosity of glass melt.

⑤ Table salt: Table salt vaporizes and volatilizes at high temperature to promote glass clarification.

⑥Sodium fluorosilicate: Sodium fluorosilicate is used as clarification aid, cosolvent and turbidity aid.

⑦Sodium nitrate: NaNO3 has a low melting point and decomposition temperature. It can be decomposed into Na2O, N2, O2 when heated, and can form a eutectic with silicon dioxide (SiO2). It also has strong oxidation and clarification effects, thus accelerating the melting of glass. system.

⑧Cullet glass: The use of cullet can not only use waste, but also accelerate the glass melting process and reduce the heat consumption of melting under reasonable use, thereby reducing the production cost of glass and increasing output.

Post time: Dec-28-2021