Shrinkage binder effects

Another potential problem in water-soluble binder systems is the achievement of easily processable viscosities. Celluloses are used as thickeners in some industries (food, pharmaceutical), and they behave similarly in tape casting. PVA slips also tend toward higher viscosities, but not to the extent of celluloses. Reported slip recipes have addressed this thickening effect by using additional water to lower slip viscosities. This results in castable slips, but it also results in wet dry ratios of 6.5 1 or 8 1, or z-dimension shrinkage of 77%P The additional water also results in comparatively low solids to solids plus solvent ratios. Some reported formulations display viscosities of 37,500 mPa-s (cP) at 38.6 wt% solids,>17,800 mPa-s (cP) at 43 wt%, or solids loading as low as 17.3 wt%. The role of pH on the viscosity of the multicomponent slip is not widely reported. 

---