Powder Technology, Vol.332, 27-32, 2018
Preparation of core/shell structured silicate composite filler and its reinforcing property
Core/shell structured composite particles have been frequently reported to enhance the performance of products. In this work, core/shell structured calcium silicate composite filler was prepared to mitigate the negative effect of calcium silicate filler on paper strength and allow for increasing filler content in paper. Calcium silicate as the core which was used as silica source, and reacted with hydrochloric acid to form SiO2 as shell. Results from XRD, FT-IR, SEM and BET specific surface area analysis indicated that nano-SiO2 particles were formed on the surface of calcium silicate. The active Si-OH group on the surface of the composite filler enhanced the bondability between fillers and fibers. Physical testing of handsheets showed notable improvement in mechanical properties (tensile index increased 33.0%, tear index increased 18.1%). In addition, the Si-OH group also helped to flocculate of composite filler to larger particles, which was also beneficial to the paper strength. (C) 2018 Elsevier B.V. All rights reserved.