Purpose/Aim
The oil-paper insulation in transformers is subjected to complex mechanical and thermal stresses in the process of operation, and it will gradually deteriorate with the increase of operating life. In order to improve the mechanical properties of insulating paper, a method of preparing insulation paper by doping nanocellulose was proposed in this paper. By performance test and control of doping content, the influence of nanocellulose on modified insulation paper was studied.
Experimental/Modeling methods
Cellulose nanowhisker (CNW) and nanofibrillated cellulose (NFC) were added into the paper pulp to make modified insulation paper. Scanning electron microscopy (SEM) was used to observe the dispersion of nanoparticles in insulation paper doped with different types and mass fractions of nanocellulose. By tensile strength test, the mechanical properties of the modified insulation paper were measured when nano-cellulose was doped.
Results/discussion
In this paper, the preparation method of insulation paper doped with nanocellulose was studied, the mechanical properties of modified insulation paper under deteriorating conditions were compared, and the mechanical life of modified insulating paper under different doping conditions was analyzed. The results show that the doping of nanocellulose can improve the mechanical properties of insulation paper in a certain range of mass fraction.
Conclusions
The results show that doping nanocellulose can introduce more hydroxyl groups, which can form hydrogen bonds with adjacent cellulose chains, enhance the bonding strength between chains, and improve the tensile strength of insulation paper significantly.
Appendix

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