About the difference between PIR sandwich panel and PUR sandwich panel

author: serena

(1) The fireproof performance of PIR  panel  is better than that of PUR board and the mechanism of the difference in fireproof performance:  
PUR and PIR are two foam systems.Polyols are divided into polyester polyols and polyether polyols. PUR is a foam system generated by the reaction of polyether polyols and isocyanates, and PIR is formed by the reaction of polyester polyols and isocyanates.  The isocyanate index of PUR plate is usually between 110 and 120, and the crosslinking degree of PUR foam system mainly depends on the functional degree of polyether polyols.  However, with the increasingly strict requirements of fire rating, PUR panel  faces great challenges in meeting the fire code. Usually, in order to meet the requirements of the fire code, a large number of flame retardants will be added to the formula system, but at the same time, it will affect the compression strength, dimensional stability and other physical properties of the foam, and improve the cost of the product.  Crosslinking degree group of PIR system depends on the excessive isocyanate (reaction, isocyanate index reached 200 ~ 300, usually under the corresponding catalyst, excessive isocyanate can generate six-member ring, since the reaction gives bubble collective crosslinked also through their own molecular structure of six-member ring to make burning coking coal, improve the fireproof  performance of foam system.  
(2)PIR panel has simple reaction and can use low-cost raw materials;  
(3)PIR panel can give the product better high and low temperature dimensional stability, lower thermal decomposition rate, combustion process can form a protective carbon layer  
(4) The mechanical strength of PIR panel is superior to PUR panel  
(5) High production efficiency of PIR panel .  

Disadvantages of PIR sandwich board  compared with PUR sandwich board :  
(1) High brittleness and fluidity lower than PUR sandwich  panel :  
(2) Poor cohesiveness, and the bonding force with the surface material is only 1/2 of PUR sandwich board  :  
(3)PIR sandwich board  has the property of sharp secondary foaming, which will affect the performance of the panel  surface