Testing the insulation value of blowing agents

Essentially an experimental procedure based on the transient hot wire method, with apparatus developed in cooperation with the University of Stuttgart, Germany, it has been tested for vapour-phase thermal conductivity of 10 blowing agents, of which CFC-11 showed the lowest level. Of the alternatives, cyclopentane showed the next best results, especially at low temperatures (which is a key point for refrigeration). 

The method is claimed to give accurate results and provide absolute values. No calibration is required (as, for example, when a gas chromatograph is used) and the method and resulting data are useful in modelling and predicting the insulation value of the foam produced with the blowing agent. 

Endex ABS 50 is a new endothermic foaming agent for a wide range of thermoplastics, including polycarbonate, polyphenylene ether, nylon. 

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