Supramolecular Structural Variations in iPP/ZnO Nanocomposites: Effect on Optical and Dielectric Performance
Sevinj Nuriyeva1, Habiba Shirinova2, Aynura Karimova3
1Nano Research Laboratory, Center of Excellence in Research, Development and Innovation, Baku State University, 33 Z. Khalilov Street, Baku 1148, Azerbaijan.
ACS Omega
|July 3, 2026
Summary
Controlling the cooling rate of isotactic polypropylene (iPP) nanocomposites with zinc oxide (ZnO) nanocrystals influences their structure and properties. Slow cooling enhances optical properties like photoluminescence (PL) but reduces dielectric performance.
Area of Science:
- Materials Science
- Polymer Science
- Nanotechnology
Background:
- Isotactic polypropylene (iPP) is a versatile polymer with applications in various fields.
- Zinc oxide (ZnO) nanocrystals offer unique optical and electrical properties.
- Understanding the structure-property relationships in iPP/ZnO nanocomposites is crucial for material design.
Purpose of the Study:
- To investigate the effect of melt-cooling rate on the structural, optical, and electrical properties of iPP/ZnO nanocomposites.
- To explore how different cooling rates influence the phase formation and morphology of the nanocomposites.
- To establish a process-structure-property relationship for tunable material performance.
Main Methods:
- Synthesis of iPP/ZnO nanocomposites using solution-blending and hot-pressing.
- Controlled cooling of nanocomposite melts under three modes: slow cooling, ice-water quenching, and liquid-nitrogen quenching.
- Characterization using X-ray diffraction (XRD), atomic-force microscopy (AFM), photoluminescence (PL) spectroscopy, and dielectric measurements.
Main Results:
- Slow cooling promoted the formation of both α- and γ-phases in iPP, while rapid cooling yielded only the α-phase.
- Morphological analysis revealed rougher surfaces in slow-cooled samples.
- Slow cooling increased photoluminescence (PL) due to γ-phase interactions but decreased interfacial polarization, consistent with Maxwell-Wagner-Sillars (MWS) theory.
Conclusions:
- Melt-cooling rate is a critical parameter that governs supramolecular structure and interfacial ordering in iPP/ZnO nanocomposites.
- Precise control over cooling rate allows for simultaneous tuning of optical (PL) and dielectric properties.
- This study demonstrates the potential of processing-induced modifications for designing advanced materials for optoelectronics, flexible dielectrics, and coatings.
