Polyurethane foams containing nanoclay were fabricated by mixing Nanocor? I-28E, a organically modified clay. Nanoclay was irradiated with polymeric isocyanate (Part A) by means of high power ultrasonic processor. The solution was then mixed with polyol (Part B) through a high speed mechanical mixer. The mixture was cast into rectangular mold to make nanophased foam panels. Test coupons were extracted from the foam plates to characterize dynamic mechanical properties using DMA and static flexural strength. From DMA studies, it was found that the storage modulus increased from 157 MPa (for neat foam) to 254 MPa and 239 MPa respectively for 0.5% and 1% nanoclay-foams. Glass transition increased initially from 118° C (for neat foam) to 128° C (for 0.5% nanoclay-foam) before reducing to 115° C (for 1% nanoclay-foam). Flexural strength showed a similar trend with neat foam exhibiting a value of 7.97 MPa, 0.5% nanoclay-foam 8.87 MPa and 1% nanoclay-foam 7.72 MPa. Flexural modulus increased from 240 MPa (for neat foam) to 270 MPa (for both 0.5% and 1% nanoclay-foam). However, strain to failure under flexure decreased from 6.14% for neat foam to 4.73% and 4.15% for 0.5% and 1% nanoclay-foam respectively.
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