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The special structure of the extruded board has high compressive strength and strong impact resistance. The compressive strength is above 500Kpa and can withstand the ground load of various systems. It is a thermal insulation board material. In the later stage, it needs to be heated to add polymers or catalysts, and some pores will be formed on the surface, and these pores are continuous closed-cell structures.

Thermal insulation should be good and compressive strength should be high, but this is contradictory. High compressive strength and high product bulk density require low foaming ratio, and thermal insulation performance is easy to decline. Good thermal insulation and high foaming ratio make the product bulk density light. The closed-cell rate inside the extruded board can reach more than 99%, forming a vacuum layer to avoid air flow and heat dissipation, ensuring its long-lasting and stable thermal insulation performance. In other words, the higher the closed-cell rate, the better its thermal insulation performance.

Generally speaking, the color of high-quality extruded boards should be white, but most of the extruded boards on the market are colored, but this does not affect it. As long as the color is positive and there is no gray, black or dark phenomenon, it is good.

If the inferior extruded board gets wet during storage or use, or if it is soaked in water for a long time due to other reasons, it is easy to cause the extruded board to deform. In particular, the extruded board is not soaked in water evenly. Extruded boards, adhesives and mesh cloths should be tested when they enter the site, including the thermal conductivity, density, compression strength of the extruded board, the bonding strength of the adhesive, and the mechanical properties and corrosion resistance of the mesh cloth.