Phenolic Board--the First Choice for Thermal Insulation Materials(part 1)

2023-02-07

Phenolic Board--the First Choice for Thermal Insulation Materials(part 1)

Phenolic insulation board

The application of thermal insulation materials in the construction industry is customarily divided into two categories: inorganic matter (divided into board, block, slurry or fiber according to shape) and organic matter (including thermosetting and thermoplastic).

Only through the comprehensive comparison among materials can it be identified, and the phenolic insulation board ranks first among the insulation materials with absolute advantages. Its advantages are listed in detail below.

1. Phenolic insulation board has the highest fire rating

Phenolic foam insulation materials (boards) are thermosetting plastics. Phenolic foam is made of phenolic resin as the main raw material, which is cross-linked and foamed by itself under the action of a catalyst, and solidified and formed. Without adding any flame retardant, it has fixed fireproof performance. It has a bulk polymer, stable aromatic structure. According to the fire rating of the GB8624 standard, the phenolic foam itself can easily reach the B1 fire rating, which is close to the A class, and is located between the B1 and A class combustion ratings. According to relevant information, Japan has designated phenolic insulation boards as "quasi-non-combustible" products.

Phenolic foam insulation material or specifically called phenolic insulation board, uses phenolic resin with inherent fireproof and temperature resistance as the main raw material. The outstanding feature of the phenolic insulation board produced through technical modification is that it forms a carbonized skeleton and gaseous substances such as CO and CO2 under direct contact with an ultra-high temperature open flame. The gas can not only dilute the combustible gas and oxygen concentration in the combustion zone, but also has a covering effect. There is no flame spread and spread, only charring on the surface of the phenolic foam without molten dripping. Phenolic foam board exhibits excellent resistance to flame penetration.

Polyurethane rigid foam (PUR) or polyisocyanurate rigid foam (PIR) is a two-component main raw material with polyether and isocyanate. Under the action of catalyst and curing agent, it is cross-linked and cured. At present, it is mainly through technical measures such as adding fire prevention additives, or isocyanate trimerization, or using special fireproof polyether, to improve the fireproof level of polyurethane rigid foam, but it is difficult to reach B1 level for spray foam.

Thermoplastic insulation materials (EPS/SMEPS/XPS) are linear polymers and belong to thermoplastics. Thermoplastic insulation materials and thermosetting modified polystyrene boards, because the addition of flame retardant materials is more random, it is this process that determines that they can reach the B1 level of fire protection. Its quality is very unstable, with flaws and large fluctuations.

Facts have proved that there have been many major fire accidents in the application or construction of organic thermal insulation materials, thermoplastic thermal insulation materials and polyurethane rigid foam. However, no fire accidents have occurred in the phenolic insulation material (board) either during construction or in application.

2. Phenolic insulation board has the highest oxygen index

Oxygen index refers to the minimum oxygen content required to maintain stable combustion of foam in the mixed flow of oxygen and nitrogen under specified conditions, expressed in terms of the volume percentage of oxygen in the mixed oxygen and nitrogen.

Oxygen index is an expression method to evaluate the flammability of plastics and other polymer materials. The atmosphere we live in contains 21% oxygen, that is, the oxygen index is 21%. When the oxygen index of the material is greater than 26%, it cannot be burned in normal air. Therefore, it is generally considered that when the oxygen index is less than 22%, it is a flammable material.

In other words, the level of the oxygen index represents the ease of combustion of the material. A material with a relatively high oxygen index indicates that the material is relatively non-combustible and will delay the spread of the fire in the event of a fire. On the contrary, if the oxygen index of the material is relatively low, it means that the material is relatively easy to burn. When a fire breaks out, the fire spreads rapidly and it is difficult to rescue.

Follow up please see Phenolic Board--the First Choice for Thermal Insulation Materials(part 2).

Phenolic insulation board - 1