Effects of temperature and crystallinity on partial discharge resistance of poly-L-lactic acid

Yoshimichi Ohki, Kazuhiro Miyata

    Research output: Contribution to journalArticle

    3 Citations (Scopus)

    Abstract

    Partial discharge (PD) resistance of biodegradable poly-L-lactic acid (PLLA) was examined at temperatures between room temperature and 70°C, namely at around the glass transition temperature of 57°C. The PD activity becomes more pronounced at temperatures above 60°C, reflecting that the permittivity increases in the rubber state. Furthermore, we have changed the crystallinity of PLLA by drawing or annealing thermally, and have examined its effect on the PD resistance. Although the depth eroded by a fixed period of PD degradation becomes shallower when the sample was crystallized by the drawing or the heat treatment, its reduction ratio is almost equal to the reduction ratio of PD activities due to the decrease in permittivity. Therefore, it is hard to assume that crystallization of PLLA improves its PD resistance to a unit amount of charge.

    Original languageEnglish
    Pages (from-to)323-327
    Number of pages5
    JournalIEEJ Transactions on Electrical and Electronic Engineering
    Volume5
    Issue number3
    DOIs
    Publication statusPublished - 2010 May

    Fingerprint

    Partial discharges
    Lactic acid
    Temperature
    Permittivity
    Rubber
    Crystallization
    Heat treatment
    Annealing
    Degradation

    Keywords

    • Biodegradable polymer
    • Crystallization
    • Glass transition
    • Partial discharge
    • Poly-L-lactic acid

    ASJC Scopus subject areas

    • Electrical and Electronic Engineering

    Cite this

    Effects of temperature and crystallinity on partial discharge resistance of poly-L-lactic acid. / Ohki, Yoshimichi; Miyata, Kazuhiro.

    In: IEEJ Transactions on Electrical and Electronic Engineering, Vol. 5, No. 3, 05.2010, p. 323-327.

    Research output: Contribution to journalArticle

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