Clay filled rigid polyurethane foams

P.M. STEFANI; L. ESPÓSITO; L.B. MANFREDI; A. VAZQUEZ

Polymer and Biopolymer Analysis and Characterization

Nova Science, Pubs.

Lugar: NY; Año: 2007; p. 127 - 137

Rigid polyurethane foam were prepared from a commercial system using clay as filler (0, 5, 10 and 20 wt.%). The effect of foaming process on the dispersion of clay in the polymeric matrix and their consequences on the physical properties of the final foams were investigated. X-ray diffraction data indicate the intercalation of polymer chains inside the interlayer spacing of clay. The highest spacing layer was observed in the sample modified with 5wt% of clay. Transmission electron microscopy photographs showed that the clay layers were dispersed heterogeneously in the polymeric matrix. Regions with some agglomerates, intercalation of the polymeric chain in the clay galleries and small amount of the exfoliated clay sheet were observed. Also the analysis by TMA showed the alignment of silicate layers as a result of biaxial flow during the foaming process. A universal testing machine was used to investigate the compressive properties of the filled foam. The modulus and compressive strength showed a maximum for a clay content of 5 wt.%. However, the thermal stability did not change with the clay content. Keyword: clay, polyurethane, foam, mechanical propertiesclay, polyurethane, foam, mechanical properties