Improvement of Paper Properties Using Starch-Modified Precipiated Calcium Carbonate Filler

摘要

Commercial filler, precipitated calcium carbonates (PCC), were modified with corn and potato raw starches.rnThese modified fillers were used to improve the sheet strength in high filler content papers. The filler treatmentrnwas performed by mixing the PCC filler with uncooked starch at high solid content (>45%), and then cookingrnthe mixture. It was found that the water content in the cooking mixture plays an important role in the fillerrnmodification. Experiments indicate that the PCC could be coated by starch gel by the method described in thisrnpaper. No significant dissolution of the PCC coated starch gel was found during the papermaking process.rnHandsheet physical properties including tensile, tearing, and folding could be improved dramatically withrnstarch-coated PCC compared to the conventional method of adding cooked starch. These improvements werernconsistent when different types of starch were evaluated. Negligible differences in physical and optical paperrnproperties were observed among the starch-modified PCC fillers added handsheets using different types ofrnstarches.