Analytical interpretations of static and dynamic mechanical properties of thermoplastic elastomer toughened PLA blends

作者：Nehra Ranjana; Maiti Saurindra Nath; Jacob Josemon

来源：Journal of Applied Polymer Science, 2018, 135(1): 45644.

DOI：10.1002/app.45644

<jats:title>ABSTRACT</jats:title><jats:p>Poly(lactic acid) (PLA) was melt blended with thermoplastic elastomer (TPE) styrene–ethylene–butylene–styrene‐<jats:italic>g</jats:italic>‐maleic anhydride (SEBS‐<jats:italic>g</jats:italic>‐MA) copolymer using a micro compounder which used melt recirculation approach for efficient dispersion of SEBS‐<jats:italic>g</jats:italic>‐MA in PLA. The SEBS‐<jats:italic>g</jats:italic>‐MA volume fraction (Φ<jats:sub><jats:italic>d</jats:italic></jats:sub>) was varied between 0.07 and 0.48. Dynamic mechanical analysis showed 10.4 °C decrease in glass transition temperature at Φ<jats:sub><jats:italic>d</jats:italic></jats:sub> = 0.48. Differential scanning calorimetry results exhibited shift in cold crystallization temperature to a higher temperature in the presence of SEBS‐<jats:italic>g</jats:italic>‐MA. Thermogravimetric analysis presented enhanced thermal stability of PLA/SEBS‐<jats:italic>g</jats:italic>‐MA blends. Tensile strength and modulus decreased while elongation‐at‐break and Izod impact strength increased in the blends. Theoretical models were employed to analyze the tensile properties of the blends in order to evaluate the blend structure. The microstructural attributes were characterized by wide‐angle X‐ray diffraction, Fourier‐transform infrared spectroscopy, and scanning electron microscopy of cryofractured, impact fractured, and tensile fractured surfaces.

• 出版日期2018-1-5