The thermal conductivity of polyethylene foams manufactured by a nitrogen solution process

The thermal conductivity, the cellular structure and the matrix polymer mor phology of a collection of chemically crosslinked low-density closed cell p olyethylene foams, manufactured by a high-pressure nitrogen gas solution pr ocess, have been studied. With the aid of theoretical models, the relative contributions of each heat transfer mechanism to the total thermal conducti vity has been evaluated. The results show that, the relative contribution o f the thermal radiation is (22-34%), and that this contribution is mainly c ontrolled by the mean cell size and by the carbon black content in the foam .