Preparation of a modified diatomite filler via polyethyleneimine impregnation and its application in papermaking

Abstract

ABSTRACT In this study, we sequentially modified diatomite (DM) particles with sodium dodecyl sulfate and polyethyleneimine with an impregnation method. Modified DM was used as both a filler and an anionic trash catcher in the papermaking process. The surface morphology, ζ potential, particle size, and Fourier transform infrared spectrum of the modified DM were investigated, and the application performance of the modified DM was evaluated through filler retention, ζ potential, drainability, and cationic demand of the papermaking furnish and the paper strength properties. The results show that the modified DM could be used as a good, novel filler in papermaking. The ζ potential of the surface of the modified DM particles was changed from electronegative to electropositive, and the particle size of the modified DM particles was increased. The retention of the modified DM filler was 16% higher than that of the unmodified DM when the filler dosage was 40%. The higher ζ potential was responsible for the higher retention of the modified DM filler. The drainability of the papermaking furnish was improved efficiently. The anionic trash in the papermaking system was anchored efficiently, and the cationic demand of the papermaking furnish decreased over 85% when the dosage of modified DM was 35%. Compared with the handsheets filled with unmodified DM, the handsheets filled with modified DM had higher strength properties. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46275