Compositions and methods for manufacturing sheets having a
starch-bound matrix, optionally reinforced with fibers and optionally including an inorganic mineral filler. Suitable mixtures for forming the sheets are prepared by mixing together water, unmodified and ungelatinized
starch granules, a cellulosic
ether, optionally fibers, and optionally an inorganic mineral filler in the correct proportions to form a sheet having desired properties. The mixtures are formed into sheets by passing them between one or more sets of heated rollers to form green sheets. The heated rollers cause the cellulosic
ether to form a
skin on the outer surfaces of the sheet that prevents the
starch granules from causing the sheet to adhere to the rollers upon gelation of the starch. The green sheets are passed between heated rollers to gelatinize the starch granules, and then to dry the sheet by removing a substantial portion of the water by
evaporation. The starch and cellulosic
ether form the binding matrix of the sheets with the fibers and optional
inorganic filler dispersed throughout the binding matrix. The starch-bound sheets can be
cut, rolled, pressed, scored, perforated, folded, and glued to fashion articles from the sheets much like paper or
paperboard. The sheets are particularly useful in the
mass production of containers, such as food and beverage containers.