In order to understand the effect of both UV radiation and isothermal crystallization temperature on LDPE/MMT nanocomposites we used one composition of LDPE/MMT nanocomposites. All samples were crystallized isothermally at two selected temperatures of 100 and 104oC for a fixed time of 5h. The crystallization temperature was chosen to be above the non-isothermal crystallization of LDPE/MMT nanocomposites. XRD showed that the material used consisted of two stable monoclinic and orthorhombic phases. Both phases have shown different respond to the crystallization process. Intercalation of clay was also affected by the crystallization temperatures and UV exposure. Results obtained from XRD, DSC and FTIR were in agreement with each other. A third phase that is thermally less stable was also observed, its thermal respond was larger since it contains low molecular weight entities which makes it more vulnerable to any UV exposure.
Key words: LDPE; montmorillonite; isothermal, crystallization; UV irradiation, nanocomposites
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