Environment friendly flame retardant PVC industrial wall panel
日期：2022/3/3 9:13:29 / 閱讀： / 來源：本站
Environment friendly flame retardant PVC industrial wall panel1. Material selection and formula design
Although PVC has many excellent properties, such as flame retardancy, aging resistance, corrosion resistance and moderate melting viscosity, but because of the strong attraction between PVC molecules, it is difficult to melt and flow. The hardness of the product and adding a certain amount of plasticizer can greatly improve the mechanical properties of PVC products. When exposed to ultraviolet light, the surface of PVC is easy to be damaged and become yellow, which is easy to be damaged by ultraviolet light. In order to improve the anti ultraviolet ability of products, a certain amount of stabilizer is added to absorb ultraviolet rays, so that the aging performance of products can be extended to 30 ~ 50 years.
Aluminum hydroxide is decomposed into Al2O and water by heating, and the reaction heat absorption can reach 1967.2kj/kgo. Aluminum hydroxide is dehydrated obviously at about 210 ℃. Adding aluminum hydroxide to plastics can effectively improve the flame retardant performance of plastics.
Hydrated zinc nitrate (FB flame retardant is a kind of inorganic additive flame retardant. Alumina trioxide not only has positive combustion performance, but also has smoke suppression function. Adding flame retardants such as oxygen oxide trioxide and hydrated zinc borate into hard PC can not only improve the smoldering performance of PVC, but also have good smoke elimination effect. In order to prepare environment-friendly flame retardant PC industrial board and realize the dual environmental protection of products and production process, a large number of experiments have been carried out The new composite heat stabilizer is used to manufacture industrial wall panels. The specific formula (mass parts) is as follows. 100 stearic acid 0.15-0.5
PVC 4 ~ 6 hydrated zinc borate, molybdenum trioxide, hydrogen cushion stabilizer, chlorinated polyethylene (CPE) 4 ~ 6 alumina and light calcium carbonate. In order to adjust and control the density of the product, a certain amount of AC foaming agent can be added At the same time, add an appropriate amount of ACR foaming adjustment. If it is necessary to further improve the tensile strength and impact properties of the product, the content of light calcium carbonate can be increased and a certain amount of coupling agent can be added. In order to further improve the aging performance of the product, 2 ~ 6 parts of UV series ultraviolet absorber can be added, and corresponding additives can be added to change the color of the product (such as 1 ~ 2 parts of titanium dioxide or
0.01 ~ 0.05 parts of phthalocyanine blue, or add 0.05 ~ 0.5 parts of medium chrome yellow, etc.) to prepare products with corresponding colors.
2. Main equipment
(1) Extruder single screw extruder can be used for both manufacturing and plate extrusion. (2) In the design of die, tool plate and die, compared with the common wall plate die, it is usually necessary to consider increasing the internal cross-sectional area of the fixed die channel and the cross-sectional area of the die. The mold of this product is transformed from an ordinary wall panel mold. Generally, we only need to pay attention to the following three aspects:
1) Increase the thickness of the forming die wall to 1.6 ~ 2mm, and the overall dimension remains unchanged, so as to facilitate the matching with the original mold.
2) Sharp corners and dead corners are not allowed on the surface of the flow channel, and the section change shall be smooth. 3) The surface roughness of the runner shall be less than 0.16.
3. Preparation process
1) Weigh each component material according to the above formula.
2) PVC, rare earth stabilizer, CPE and light calcium carbonate are successively added into the high-speed mixer for stirring at room temperature. When the temperature rises to 70 ~ 80 ℃, stop the machine, and then add stearic acid, dioctyl phthalate (DOP), zinc borate hydrate, molybdenum trioxide and aluminum hydroxide for stirring. When the temperature of plate (sheet) material 200 rises to 110 ~ 115 ℃, the material is discharged into the cold mixer and cooled to 38 ~ 45 ℃
Discharge and make loose dry mixed powder.
3. After heating the machine to the set temperature, keep it warm for 30min, and then add the prepared dry mixed powder to adjust the speed of the main machine of the granulator for granulation. The temperature of each zone of the granulator is one zone: (90 ± 5) ℃; Zone II: (105 ± 5) ℃; Zone III: (120 ± 5) ℃; Zone IV: (130 ± 5) ℃; Zone 5:
(145±5)℃; Zone 6: (140 ± 5) ℃.
4. Adjust the temperature setting according to the plasticization of the material, and no large temperature fluctuation is allowed. During extrusion molding, the temperature of each zone is one zone: (150 ± 5) ℃; Zone II: (160 ± 5) ℃; Zone III: (170 ± 5) ℃; Zone IV: (185 ± 5) ℃; Zone 5: (195 ± 5) ℃; Zone 6: (180 ± 5) ℃.
4. Product performance
According to the above formula and manufacturing method, the combustion performance of the product reaches the level of GB 8624-1997 BL (thermoplastic material). The oxygen index is ≥ 55 (standard requirement ≥ 32), the horizontal combustion reaches FH-1, and the smoke density grade is ≤ 61 (standard requirement 75). The environment-friendly flame retardant PVC industrial wallboard produced has high strength, good toughness, aging resistance, flame retardant, waterproof, thermal insulation and sound insulation. It can be used as the enclosure wall of various frame structures of industrial and civil buildings to replace metal, FRP and other corresponding products.