WOOD RESEARCH Volume 67, Number 3, 2022
Xu Sheng, Xu Peng, Du Yuting, and Zhao Puqi

Short notes: A research on the application of industrial by-product calcium sulfate whiskers in paper filling

The basic properties of calcium sulfate whiskers were studied and compared with commercial ground calcium carbonate (GCC) fillers. The modified whiskers were used for paper filling and compared with a commercial precipitated calcium carbonate (PCC). As a result, it shows that when the unmodified calcium sulfate whisker is used to fill the paper, the ash content of the handmade sheet is low because of its dissolution problem. The ash content of the paper increased obviously when the modified calcium sulfate whisker was added, which reached the ash level of PCC filling. In addition, the paper strength increased greatly, but the light scattering coefficient decreased. In addition, the strength property of the modified calcium sulfate whisker filling paper is basically the same as that of the PCC filling paper with 14.99% ash content when the ash content of the modified calcium sulfate whisker filling paper is 21.95%.

WOOD RESEARCH Volume 62, Number 4, 2017
Xu Peng

Fiber in-situ synthesis of calcium silicate for usage in fine paper

This paper researches fiber in-situ synthesis of calcium silicate that is made from sodium silicate solution extracted from fly ash, lime milk and fiber and its usage in fine paper. The in-situ synthesis technique was used to prepare man-made calcium silicate loaded in paper. The paper is in line with the copy paper standards. The experiments determined the optimum conditions for papermaking as follows, the pre-processing time of fiber immersed in the silicon solution 6h, pulp freeness 42°SR, the SiO2 concentration of the silicon solution 65.5g/L, the effective calcium concentration milk of lime 175g/L, stirring speed 550r/min, the reaction temperature 95°C, the reaction time 90min. Under these conditions, the filler retention rate in fine paper can reach more than 80%. A scanning electron Microscope-Spectroscopy (SEM-EDX), X-ray diffraction (XRD), infrared spectroscopy (FT-IR) was used to analyze paper products and structure. The results showed that the calcium silicate generated within the cell lumen, cell wall, and other open spaces of the fibers, and good bonding was demonstrated between the filler and fibers.