کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4512770 | 1624837 | 2015 | 12 صفحه PDF | دانلود رایگان |
• Bio-based additives were tested as retention and drainage agents.
• Cationic microfibrillated cellulose has a very low effect on drainage and retention.
• Chitosan used together with bentonite allows improving retention and drainage.
• Additives are more efficient with the tested bagasse pulp than with a softwood pulp.
Water soluble cationic chitosan (C-Ch) and surface-modified microfibrillated cellulose (C-MFC) were prepared and characterized. C-MFC was prepared by reaction of MFC (microfibrillated cellulose) with β-chloroethyldiethylamine followed by quaternization using methyl iodide while C-Ch was prepared by reaction of a commercial chitosan (Ch) with 2,3-epoxypropyltrimethyl ammonium chloride. C-Ch and C-MFC were characterized by elemental analysis (nitrogen content), Fourier transform infrared spectroscopy (FTIR) and surface charge determination. The prepared C-Ch and C-MFC were used with bentonite in order to improve drainage and filler retention in paper handsheets made from softwood and bagasse pulps. Dosage rates were 0.05–0.2% (w/w, weight of additive by weight of fibres) and 0.05–1% (w/w) for C-Ch and C-MFC, respectively. When used alone, these polymers did not induce any noticeable effect on drainage but they improved the retention of ground calcium carbonate (GCC). The effect of C-MFC/bentonite and C-Ch/bentonite systems on filler retention was more pronounced in case of bagasse pulp than for softwood pulp. The use of C-Ch improved filler retention more than C-MFC did. Comparisons with a commercially available cationic polyacrylamide (CPAM) showed that CPAM was the most efficient additive regarding both drainage and GCC retention, followed by Ch, C-Ch, and finally C-MFC.
Journal: Industrial Crops and Products - Volume 72, 15 October 2015, Pages 34–45