Silica surface-modification for tailoring the charge trapping properties of PP/POE based dielectric nanocomposites for HVDC cable application
Year of publication
2020
Authors
He, Xiaozhen;Rytöluoto, Ilkka;Rytöluoto, Ilkka;Anyszka, Rafal;Mahtabani, Amirhossein;Saarimäki, Eetta;Lahti, Kari;Paajanen, Mika;Dierkes, Wilma;Blume, Anke
Abstract
This paper focuses on novel insulation polypropylene/poly(ethylene-co-octene) (PP/POE) nanocomposites for High Voltage Direct Current (HVDC) cable application. The composites contain silica modified by a solvent-free method using silanes differing in polarity and functional moieties. Thermogravimetric Analysis and Fourier Transform Infrared Spectroscopy showed that the solvent-free method is an effective way to modify silica by silanes. Silica/PP/POE nanocomposites were prepared in a mini twin-screw compounder, and the effect of silica on crystallization, dispersibility and dielectric properties of the samples was investigated. Differential Scanning Calorimetry results showed that the unmodified and modified silicas acted as nucleation agents and increased the onset of the crystallization temperature of the polymeric matrix. Scanning Electron Microscopy images showed that the silica is mostly located in the PP phase matrix. For the PP/POE nanocomposites filled with unpolar silica, a higher trap density (measured by Thermally Stimulated Depolarization Current, TSDC) was found; this might be caused by the larger interfacial area due to a better dispersion of the unpolar silica in the polymeric matrix. Polar silicas introduce deeper traps than the unpolar ones, which is most likely due to the hetero-atom introduction. Nitrogen atoms were found to have the strongest effect on the charge trapping properties. According to these results, amine-modified silica is a promising candidate for PP/POE nanocomposites for HVDC cable applications.
Show moreOrganizations and authors
Publication type
Publication format
Article
Parent publication type
Journal
Article type
Original article
Audience
ScientificPeer-reviewed
Peer-ReviewedMINEDU's publication type classification code
A1 Journal article (refereed), original researchPublication channel information
Journal
Volume
8
Article number
9088133
Pages
87719-87734
ISSN
Publication forum
Publication forum level
2
Open access
Open access in the publisher’s service
Yes
Open access of publication channel
Fully open publication channel
License of the publisher’s version
CC BY
Self-archived
Yes
Other information
Fields of science
Computer and information sciences; Electronic, automation and communications engineering, electronics; Materials engineering
Keywords
[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Internationality of the publisher
International
Language
English
International co-publication
Yes
Co-publication with a company
No
DOI
10.1109/ACCESS.2020.2992859
The publication is included in the Ministry of Education and Culture’s Publication data collection
Yes