What is the relationship between the thermal conductivity and wet rent factor of the insulation material?

Definition of thermal conductivity: It is usually represented by the character “λ”, and the unit is: Watt/meter·degree (W/(m·K), where K can be replaced by ℃. Thermal conductivity (also known as thermal conductivity or thermal conductivity) is a measure of the thermal conductivity of a material. It characterizes the thermal conductivity of a material under stable heat transfer conditions (under stable heat transfer conditions, a material of 1 meter thickness, with a temperature difference of 1 degree on both sides, transfers heat through an area of ​​1 square meter in 1 second). It indicates that thermal conductivity is one of the inherent physical and chemical properties of the material itself, and is related to the type, state (gas, liquid, solid) and conditions (temperature, pressure, humidity, etc.) of the material. Numerically, thermal conductivity is equal to the heat flux density generated by the inward contraction of an object under the action of a unit gradient. Different materials have different thermal conductivity values. As far as insulation materials are concerned, The higher the thermal conductivity, the worse the insulation performance. Generally speaking, the thermal conductivity of solids is greater than that of liquids, which is greater than that of gases.

The wet rent factor µ is a parameter that characterizes the material’s ability to resist water vapor penetration and is a dimensionless quantity. The unit is m, which means that it is equivalent to the water vapor permeability of air of m. It describes the material performance, not the performance of the product or structure.

For insulation materials with the same initial thermal conductivity K but different µ, the higher the µ value, the more difficult it is for water vapor to enter the material, so the thermal conductivity rises more slowly, and the longer it takes to reach insulation failure, and the longer the service life.
When the µ value is lower, the thermal conductivity reaches the failure value in a shorter time due to the rapid penetration of water vapor. Therefore, only a thicker design thickness can achieve the same service life as high µ value materials.
Jinfulai products use high wet rent factors to ensure relatively stable thermal conductivity, so a thinner initial thickness can ensure service life.

What is the relationship between the thermal conductivity and wet rent factor of the insulation material?

Definition of thermal conductivity: It is usually represented by the character “λ”, and the unit is: Watt/meter·degree (W/(m·K), where K can be replaced by ℃. Thermal conductivity (also known as thermal conductivity or thermal conductivity) is a measure of the thermal conductivity of a material. It characterizes the thermal conductivity of a material under stable heat transfer conditions (under stable heat transfer conditions, a material of 1 meter thickness, with a temperature difference of 1 degree on both sides, transfers heat through an area of ​​1 square meter in 1 second). It indicates that thermal conductivity is one of the inherent physical and chemical properties of the material itself, and is related to the type, state (gas, liquid, solid) and conditions (temperature, pressure, humidity, etc.) of the material. Numerically, thermal conductivity is equal to the heat flux density generated by the inward contraction of an object under the action of a unit gradient. Different materials have different thermal conductivity values. As far as insulation materials are concerned, The higher the thermal conductivity, the worse the insulation performance. Generally speaking, the thermal conductivity of solids is greater than that of liquids, which is greater than that of gases.

The wet rent factor µ is a parameter that characterizes the material’s ability to resist water vapor penetration and is a dimensionless quantity. The unit is m, which means that it is equivalent to the water vapor permeability of air of m. It describes the material performance, not the performance of the product or structure.

For insulation materials with the same initial thermal conductivity K but different µ, the higher the µ value, the more difficult it is for water vapor to enter the material, so the thermal conductivity rises more slowly, and the longer it takes to reach insulation failure, and the longer the service life.
When the µ value is lower, the thermal conductivity reaches the failure value in a shorter time due to the rapid penetration of water vapor. Therefore, only a thicker design thickness can achieve the same service life as high µ value materials.
Kingflex products use high wet rent factors to ensure relatively stable thermal conductivity, so a thinner initial thickness can ensure service life.
If you have any other technical question, please feel free to contact with Kingflex team.