Work

Failure investigation and degradation study of long term hydrothermally stressed PVC reinforced with ZnO nanocomposites for cable insulation applications

Year: 2026

Type: article

Abstract: Water and temperature are critical environmental stresses that significantly affect the performance and longevity of insulation systems, particularly polymeric insulators. These factors lead to the degradation of the physical and chemical properties of polymers, ultimately resulting in failure. To investigate this, ZnO-based PVC nanocomposites (PZ0, PZ2, PZ4, and PZ6) were developed with varying concentrations of ZnO (0, 2, 4, and 6 phr). These nanocomposites were subjected to hydrothermal aging for 5000 h, divided into five cycles of 1000 h each, to assess their structural stability and performance over prolonged exposure to harsh conditions. Characterization of the nanocomposites was performed using techniques such as X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The analyses revealed that the nanocomposites generally outperformed neat PVC in terms of structural integrity and resistance to aging. Notably, PZ2 exhibited the highest contact angle of 78° after the aging period, indicating improved hydrophobicity. Additionally, surface roughness measurements showed that PZ2 had significantly less roughness compared to the other composites, suggesting better durability and performance against environmental stresses. The FTIR analysis highlighted substantial degradation of the polymer structure, with all samples experiencing over 80% chain scission after 5000 h of aging. In particular, PZ4 demonstrated 56% and 86% degradation in specific absorption bands related to -CH2 stretching and C–C bending. Thermal stability was assessed using differential scanning calorimetry (DSC), which indicated that hydrothermal aging affected the melting points of the composites. Despite this, effective dispersion of the ZnO nanofiller within the polymer matrix provided enhanced stability, mitigating some adverse effects of aging. The failure analysis showed that PZ0 experienced 77% degradation after the first aging cycle, while PZ4, PZ0, and PZ6 exhibited 55%, 50%, and 66% degradation, respectively, underscoring the critical role of nanocomposite formulation in enhancing performance under environmental stress.

Source: Scientific Reports

DOI: 10.1038/s41598-025-01544-8

Authors: Faiza Faiza, Safi Ullah Butt, Abraiz Khattak, Azhar Mahmood, Yasin Khan, Khalid Hamad AlKhalid

Institutions: Case Western Reserve University, University of Waterloo, National University of Sciences and Technology, King Saud University

Language: English

Topic: Polymer Science and PVC

Subfield: Polymers and Plastics

Field: Materials Science

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $2,690