ABSTRACT:In order to improve the strength properties of high filler filled papers, a new technique of coating starch on the clay surface was developed. The stability of the coated starch and its effects on paper properties were studied. It was found that the starch coated on the clay surface swelled in water. This swelled starch film on the filler surface contributes significantly to the filler-filler bonding. The strength properties of handsheets made from starch coated clay, even with unmodified corn starch, could be increased by more than 15% versus those from the traditional method of adding cationic or amphoteric potato starch directly to 50% bleached softwood pulp/50% bleached hardwood pulp. This research suggests that the starch coated filler can be used to make high filler content paper products.
AbstractEucalyptus residues from pulp mill were pretreated with aqueous ammonia soaking (AAS) method to improve the efficiency of enzymatic hydrolysis. The optimized condition of AAS was obtained by response surface methodology. Meanwhile, hydrogen peroxide was introduced into the AAS system to modify the AAS pretreatment (AASP). The results showed that a fermentable sugar yield of 64.96 % was obtained when the eucalypt fibers were pretreated at the optimal conditions, with 80 % of ammonia (w/w) for 11 h and keeping the temperature at 90 °C. In further research it was found that the addition of H2O2 to the AAS could improve the pretreatment efficiency. The delignification rate and enzymatic digestibility were increased to 64.49 % and 73.85 %, respectively, with 5 % of hydrogen peroxide being used. FTIR analysis indicated that most syringyl and guaiacyl lignin and a trace amount of xylan were degraded and dissolved during the AAS and AASP pretreatments. The CrI of the raw material was increased after AAS and AASP pretreatments, which was attributed to the removal of amorphous portion. SEM images showed that microfibers were separated and explored from the initial fiber structure after AAS pretreatment, and the AASP method could improve the destructiveness of the fiber surface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.