熱門關鍵詞：濟南彩鋼板 | 濟南復合板 | 濟南彩鋼瓦 | 濟南c型鋼 | 濟南鋼結構 |
With the increase of PAPI dosage, the crosslinking degree of foam increases, and the strength and stiffness increase. However, if PAPI is used too much, the foam will become brittle and the core material will crack easily.
First of all, the selection of polyether polyols is the most important. Polyether polyol is one of the basic raw materials for rigid polyurethane foam. It affects the physical and mechanical properties, dimensional stability and foaming process properties of foam core. The polyether model was determined according to initiator, hydroxyl value and viscosity.
應選用乳化能力強的泡沫穩定劑。主要控制氣泡孔的大小，保持氣泡孔的穩定，防止氣泡孔的坍塌。硅酮泡沫穩定劑在這方面效果較好，其用量可在1.5 ~ 2.5(質量分數)范圍內調節發泡劑的種類和用量，直接影響聚氨酯硬泡的密度、強度等物理性能。
Foam stabilizer with strong emulsifying capacity should be selected. It mainly controls the size of the bubble hole, maintains the stability of the bubble hole, and prevents the collapse of the bubble hole. Silicone foam stabilizer has better effect in this respect, and its dosage can regulate the type and dosage of foaming agent in the range of 1.5 ~ 2.5 (mass fraction), which directly affects the physical properties of polyurethane rigid foam, such as density and strength.
Foaming agent can not only regulate and control the density and performance of foaming products, but also reduce the combined viscosity of polyether, improve the foaming process, improve the fluidity of foam, and facilitate the formation of foam. In view of the need of sustainable development strategy, the use of fluorocarbons which are harmful to the ecological environment is limited, and the use of alternative foaming agents is also limited.
Choosing catalyst can choose delayed catalytic system, make the interval between milky white time and gel time longer, effectively improve the fluidity of foaming system and improve the performance of foam, so that it is suitable for production process operation. The uniformity of cavity foam, the fineness of the foam, the closing rate of foam and other factors have great influence on the overall insulation performance. These factors are related to the degree of adhesion between the foam and the hollow wall, and the stability of the foam.
Flame retardants can improve the flame retardancy of foam plastics, but the effect of flame retardants on foaming is greater during foaming process. The performance and dimensional stability of foamed plastics can be guaranteed on the premise of improving the flame retardant effect.
Polyurethane composite board has better wear resistance and corrosion resistance, which can be very prominent in building insulation, heat insulation, sound absorption and noise reduction, so how to choose better is very important. Of course, it is necessary to know more about the quotation of polyurethane composite board.