Analysis Of The Stability And Adhesion Properties Of Microstickies Originated From Papermaking Chemicals

Currently,recycling paper has become one of the most important materials in the papermaking industry.However,the utilization of recovered paper and extent of whitewater circulation has increased continuously,and microstickies in the whitewater have a greater influence on the paper machine running and product quality.Meanwhile,the more complex sources and properties of stickies also bring a series of difficulties to its research.Analyzing the properties of stickies from different sources is helpful to understand the problems of stickies comprehensively.In this study,the common sizing agent,alkyl ketene dimer(AKD),and the coating binder carboxylated-butadiene latex(XSBRL),were taken as whitewater microstickies to investigate their stability and adhesion properties as well as the effect of other components in whitewater on the adhesion properties of stickies originated from papermaking chemicals.The results are as follows:Two kinds of microstickies originated from papermaking chemicals were sticky and in high elastic stated in papermaking system.With the temperature increasing,the aggregation tendencies of these two stickies were slightly increased.XSBRL was more sensitive to temperature and its aggregation degree was higher than AKD's.When the system temperature was kept at 50 ?,the aggregation stated of two stickies increased slightly and changed marginally with time went on.The effect of mechanical agitation on the particle size distribution of the two stickies were related to the strength of agitation.With the change of the concentration of stickies in the system,these dispersion/aggregation trends were different.When there was only microstickies originated from papermaking chemicals in suspension,the adhesion efficiency of microstickies on the hydrophobic surface was higher and increased with the increase of microstickies concentration.Other components,such as fine fiber,fillers and Pressure Sensitive Adhesives(PSAs),appeared in suspension,the adhesion properties of microstickies were affected by these components:There are differences in the adhesion properties of AKD and XSBRL on different surface when fine fibers and Precipitated Calcium Carbonate exist.Compared with the fine fractions and the hydrophobic material surface,microstickies originated from papermaking chemicals will preferentially adhere on the former surface,which will weaken its adhesion on the hydrophobic surface and decreased with the increase of its.When fine fibers and PCC exist at the same time,they have stronger effect on microstickies from paper chemicals,which leads to weaker adhesion on hydrophobic materials.Fines,Pressure Sensitive Adhesives and microstickies originated from papermaking chemicals coexist in the suspension,they binded with each other,which resulted a large number of stickies kept in suspension.What's more,Precipitated Calcium Carbonate can reduce the surface viscosity of sticky particles,making it difficult to adhered on hydrophobic materials.