
Influence of antioxidants in epoxy-anhydride resin used for HV applications
Author(s) -
Chau Hon Ho,
E. Logakis,
A. Krivda
Publication year - 2018
Publication title -
proceedings of the nordic insulation symposium
Language(s) - English
Resource type - Journals
ISSN - 2535-3969
DOI - 10.5324/nordis.v0i23.2456
Subject(s) - epoxy , materials science , composite material , polymer , thermal stability , degradation (telecommunications) , thermoplastic , polyethylene , gravimetric analysis , dielectric strength , dielectric , glass transition , chemistry , organic chemistry , telecommunications , optoelectronics , computer science
In this work, various antioxidants with different chemical structures and functionalities were investigated in respect to their influence in the processibility and properties of a standard epoxyanhydride resin formulation used in HV applications. Such antioxidants are mainly used in thermoplastic materials as they are known for their long- and shortterm stabilizing effect against thermal and thermooxidative degradation. They are also used as UV stabilizers against decomposition and discoloration of the polymer and as metal deactivators by catching and eliminating metal ions. Recently, the use of such antioxidants as voltage stabilizers in cross-linked polyethylene has been reported showing a significant increase in breakdown voltage.Our investigations show that the processing requires additional mixing steps in order to completely dissolve antioxidants in the epoxy formulation. While little amounts of antioxidants or voltage stabilizers have a large influence in thermoplastics regarding thermal stability and electrical properties, the studied antioxidants in a concentration range of 1-5 weight-% show surprisingly only little impact in breakdown voltage as well as in dielectric properties and also in degradation behavior as detected by thermo-gravimetric analyses. Only the glass transition temperature of the cured epoxy resin is decreased in a few cases where the antioxidants have a plasticizing effect.