1. Highly foamed plastic sheet
        Expandable particles are pre-foamed, and then molded and foamed to form various high-foamed products and plates. Its structure and working principle are similar to those of a horizontal hydraulic press. After adding EFS particles into the mold cavity, heating, foaming and expanding, and cooling and shaping, a polystyrene foam board can be obtained. The processing conditions are heating steam pressure 98kPa, heating time 35-408, water cooling time 420-480s. The pre-expanded particles will expand after being softened by heat and bond to each other into a body. Since the plate is generally thicker, there is a temperature gradient between the center and the surface. In addition, the stress state of the plate surface and the center is different. The foam particles near the mold wall receive the outward expansion force of the center particle and the reaction force of the mold wall to the inside, and the metal mold wall can be regarded as a non-deformable body. Therefore, this stress condition makes the bulk density of the foam plastic skin on the surface of the board the highest. Then the bulk density decreases successively. Such a gradient of bulk density will also affect the quality of the foam plastic sheet, and attention must be paid to the control of its temperature and the limitation of the wall thickness. There are many ways to cut this kind of plate. Such as heating wire cutting, use 0.5 ~ 1.0mm heating wire, control voltage 6 ~ 12V. For mechanical cutting, sawing, milling, etc. can be used. This kind of board can also be processed like wood with woodworking tools.
      Since the expandable polystyrene foam board cannot be made too thick, it is often possible to obtain a thick board by the method of multi-layer junction. In addition, in practical applications, it is often used as a heat insulation material in building materials to bond with wood, wood, cement blocks, etc. The conditions for commonly used adhesives are: the physical strength of the expandable polystyrene foam board itself is not very high , So the bonding force of the binding agent does not have to be too large;

      ①The bond strength is reached within 24h after bonding.

      ② Solvent-based adhesives cannot be used to prevent the plate from being dissolved and damaged;
      ③The adhesive must be able to cure at room temperature;
      Commonly used binders include asphalt, polyurethane, phenolic glue and polyvinyl acetate emulsion. Asphalt adhesives are commonly used with 5, 6 asphalt and 30% gasoline, and this adhesive is evenly painted on the surface to be adhered and the plates can be firmly attached. This adhesive has good waterproof performance, but is not heat resistant. It is suitable for the adhesion of foamed plastic plates and wood, steel, cement walls and foamed plastics.
      Polyurethane adhesives can reach the bonding strength within 24 hours after bonding, and are suitable for bonding foam plastic sheets to concrete, steel, and other plastics. The adhesive layer has good chemical properties and waterproof properties, and is flexible.
     Phenolic glue can be 2127 phenolic glue, mixed with 5% to 10% petroleum sulfonic acid curing agent, and it can be cured after 24 hours at room temperature. The bonding layer has high strength, but it is brittle, so it must be applied as evenly and thinly as possible when applying.
     Polyvinyl acetate emulsion is suitable for mutual bonding with wood and foam plastic boards.