VIP for cold chain

How are VIPs built?

A Vacuum Insulation Panel consists of a rigid, highly-porous core material encased in a thin, gas-tight outer envelope. The envelope is evacuated and sealed to prevent outside gases from entering the panel. The combination of porous material and the vacuum results in an extremely high thermal resistance. The thermal resistance allows for thinner insulation in applications where space is at a premium.

Core materials for VIPs

Core Materials for VIPs require a completely open-porous structure to allow evacuation. These materials must have a sufficiently high compressive strength to withstand the mechanical pressure load. Core material classes basically comprise three structures as microporous powders, fibres and foams.

Optimum materials have a microporous structure and are able to absorb humidity. Otherwise, getters have to be added. The most common core materials are fumed silica and glass fibres. In a few cases open-cell polymer foams, such as special polyurethane or polystyrene foams, are used.

VIP envelope materials

Gas impermeability is the main factor influencing the selection of envelope materials for VIPs. In terms of a VIP’s life expectancy, its impermeability to water vapour is also important. Furthermore, a low thermal conductivity is also vital in order to keep the thermal bridge effect as low as possible along the edges of the panels. Because of the mechanical loads that occur during construction, the envelope materials should also have sufficient puncture resistance.