Order-Disorder Melt Transformation, Hierarchical Multiphase Separation and Transition, Complex Crystal Polymorphism and Self-Toughening of Isotactic Polypropylene/Poly(1-butene) Blends

02 June 2025, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

A sequential annealing, subsequent crystallization and melting procedure (SA-SMC) is developed to characterize the order–disorder melt transformation at TO-D of 190–200 °C and the corresponding temperature- and time-dependent hierarchical multiphase separation and transformation in melt-compounded isotactic polypropylene/poly(1-butene) blends. Rheological measurements confirmed the transition from an ordered melt with extended random coils to a disordered melt with quasi equilibrium globular chain conformations. Thermodynamically unstable and metastable β-form crystals of the iPP phase with a content of 44–97 wt% are generated in situ from the ordered melts without the addition of β-nucleators. Self-nucleation at 170 °C and macro-phase segregation in the melt unexpectedly result in -form crystallization in the iPP phase. Confined crystallization in the iPB nanophase favor the formation of Form I crystals. Moreover, the blends exhibit scalable self-toughened mechanical properties via synergistic control of the β-phase proportion and nano/mesophase separation. The threshold domain size of the dispersed iPB phase is less than 2 μm for tensile ductile–brittle transformation.

Keywords

Polypropylene
poly(1-butene)
ordered melt
crystal polymorphism
multiphase separation
toughening
melt blending

Supplementary materials

Title
Description
Actions
Title
Order-Disorder Melt Transformation, Hierarchical Multiphase Separation and Transition, Complex Crystal Polymorphism and Self-Toughening of Isotactic Polypropylene/Poly(1-butene) Blends
Description
Experimental details, materials, and methods, including photographs for processing and crystallization procedures; order–disorder melt transition via SA-SCM procedures; morphologies; bi-notched tensile deformation.
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.