Cell structure, thermal properties and flammability of extruded non-crosslinked LDPE/ Cloisite 20A nanoclay foams

In this study non-crosslinked low density polyethylene (LDPE) foams were produced by single screw extrusion process. In this process, talc (SiO2: 65 wt % and MgO: 35 wt %) and n-butane/n-propane were used as nucleating agent and physical blowing agent respectively, as well as glycerol monostearat(GMS) was used to obtain dimensional stability in LDPE foams. The effects of organophilic Montmorillonite (OMMT) Cloisite 20A nanoclay (with 0.1 wt%, 0.3 wt% and 0.6 wt%) on thermal conductivity, flame retardancy and morphology, of LDPE foams have been examined. To study nanoclay dispersion state in LDPE foam matrix, X-ray diffraction (XRD) method, and to observe the foam cell structure an optical microscope were used. Thermal conductivity was determined by a simple transient probe conductivity meter, and the flame retardancy of the samples was examined by flammability test. The optimum nanoclay content was determined by comparison of the results in nanocomposite and neat LDPE foams.