Study of multiblock polyamide-6/Poly-(isoprene) copolymers by positron annihilation spectroscopy

Abstract

Positron annihilation lifetime spectroscopy (PALS) has been used to determine the free volume in multiblock polyamide-6/poly-(isoprene) copolymers (PA-6/PI), synthesized via activated anionic bulk copolymerization. The diisocyanate functionalized telechelic PI, blocked with caprolactam (CL) has been used as a commoner and an activator at the same time. The elastic PI block incorporated into the main chain of PA-6 affects the amorphous and crystal phase of the copolymer leading to changing in degree of crystallinity. The positron annihilation lifetime spectroscopy (PAL) and Doppler broadening of annihilation line (DBAL) technique in a set of pure PA-6 and PA-6/PI copolymers with two different compositions have been applied and evaluation of the size of free-volume holes (pores), localized mainly in the disordered regions of the PA-6/PI copolymer by measuring the o-Ps lifetime (τ 3 ) and o-Ps intensity (I 3 ) has been performed. © Versita Warsaw and Springer-Verlag Berlin Heidelberg.

Crystallization Behaviour of Nanostructured Hybrid SiO<SUB>2</SUB>-TiO<SUB>2</SUB> Gel Glasses to Nanocomposites

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Dynamic study of free volume properties in polyethylene/styrene butadiene rubber blends by positron annihilation lifetime method

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