Interfacial compatibility of super‐tough poly(lactic acid)/polyurethane blends investigated by positron annihilation lifetime spectroscopy

Abstract

Supertough polylactide (PLA)/polyurethane (PU) blends were prepared by reactive blending of PLA with polyester polyol and toluene‐2,4‐diisocyanate. The free volume and interfacial compatibility between the two polymers were investigated by positron annihilation lifetime spectroscopy. The PU particles dispersed homogeneously in the PLA matrix and self‐assembled into a subinclusion microstructure, resulting in fibrils and significant plastic deformation occurs during impact process. More phase interface and free volume cavities formed between PLA and PU boundary because of a good interfacial compatibility between the two polymers, leading to smaller sizes of free volume cavities, and the increasing of the number of these cavities. Therefore, the toughness of PLA was greatly improved by blending PU. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46596.

Bromination Modification of Butyl Rubber and Its Structure, Properties, and Application

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The Thermal Effect on PLA And PLA / Curcumin Composite Properties under Positron Annihilation Lifetime Spectroscopy

“…By substituting the value of electron propability density in equation ( 9) instead of electron number density in equatin (7), and given that the cross-section values of 2  and 3  are known from equation ( 6) for our slow positron system, then the annihilation velocity values of parapositronium and orthoposironium can be obtained. The reverse of annihilation velocity of (p-Ps) and (o-Ps) gives the theoretical annihilation lifetime of p-Ps in polymer.…”

“…intensities, respectively [6][7][8][9][10]. The lifetime 3 ( ) o Ps   is very sensitive to the dimension and size free volume cavities .…”

“…By applying the wave function found in equation ( 15) , then substituting them in equation ( 17), then we obtain the velocity of annihilation and orthopositronium lifetime as in below [7]:…”

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