Hardening and Strength of Plastic

In order to improve the drawbacks of slow hardening and low room temperature strength of plastic materials using soft clay as a binder after construction, appropriate amounts of air hardening and heat hardening binders are often added to the polymer.
Plastics without chemical binders are called ordinary plastics. This type of plastic has low strength before sintering, but as the temperature increases, moisture escapes and the strength increases. After high-temperature sintering, the cold strength increases. But the thermal strength decreases with increasing temperature at high temperatures.
The strength of plastic with added sodium silicate increases rapidly with temperature after construction, and the mold can be removed quickly after construction. However, during the drying process, this binder may migrate to the surface of the structure or product, preventing the smooth removal of moisture and causing stress and deformation on the skin. In addition, the plastic debris after construction should not be reused. Plastic containing this binder is suitable for large kilns with longer construction periods and for use on furnace roofs.
Aluminum phosphate is the most widely used thermosetting binder in plastics, which can achieve high strength after drying and baking after construction.