Addition Of Sepiolite Research Articles

Compatibilization of semicrystalline polymeric alloys through sepiolite addition

AbstractThis study was conducted to examine the possibilities offered by sepiolite as a compatibilizing agent in the incompatible blend consisting of poly(vinylidene fluoride) and polystyrene. The effect of sepiolite on the crystalline microstructure and morphology was determined through isothermal crystallization and spherulite growth of the system under study. The effect of sepiolite on the compatibility of the system was also studied. The glass‐transition temperature was determined, as well as the Flory–Huggins thermodynamic interaction parameter through two different routes: differential scanning calorimetry and inverse gas chromatography. A parallel study was conducted for the compatible system poly(vinylidene fluoride)/poly(methyl methacrylate). © 1994 John Wiley & Sons, Inc.

Dynamic mechanical analysis of polypropylene composites based on surface‐treated sepiolite

AbstractThe dynamic mechanical properties in terms of the storage modulus G′, loss modulus G″, and loss tangent δ have been studied for polypropylene‐sepiolite composites. The effect of surface treatment on the relaxation spectra has been elucidated, and quantitative values indicating the extent of polymer‐filler interaction have been given. Analysis of the results show that the addition of sepiolite leads to an increase in the values of the modulus, a value of the glass transition temperature lower than that of unfilled polypropylene, and displacement towards higher temperatures of the αc relaxation associated with the crystalline regions. Surface treatment of the sepiolite, by esterification with organic acids of different chain length, does not have a marked effect on the relaxation spectra of the composites, even though the polymer‐filler interaction parameter decreases with respect to untreated sepiolite.

Effect of addition of sepiolite on the mechanical properties of glass fiber reinforced polypropylene

AbstractShort glass fiber reinforced polypropylene is one of the composites with the widest range of applications in the plastics industry. The partial replacement of the glass fibers by sepiolite, brings forth a hybrid composite with better mechanical properties and, as a result, enhanced compatibility and better interfacial adhesion as a consequence of the surface properties of the sepiolite. The results obtained are also interesting from a practical point of view, as they allow for considerable reductions in the costs of the formulation.