Bound aggregate method and composition

Abstract

A method and composition is disclosed which is particularly suitable for forming a firm, bound aggregate-water support for floral arrangements with at least 60% by weight water. The composition comprises a water-insoluble, water-retaining binder, such as a particulate, water-insoluble, water-swellable, cross-linked polymer, and inert non-packing, highly porous water-trapping, aggregate particles dispersed throughout, the particles being present in an amount and having a bulk density and surface area effective to disperse the composition throughout the water as the composition is added to it without hand kneading or stirring. The binder should have water retention properties of at least 100 gm/gm. The aggregate particles should have an open structure and water retention properties of at least 4 gm/gm, have a surface area of at least about 10 m.sup.2 /gm and an apparent bulk density of not over 30 lbs/sq.ft. to avoid packing. Only sufficient binder should be present to firmly bind the aggregate particles together, for example from about 0.1% to about 1.0% by weight, although higher amounts of binder can be used. Rice hull ash is preferred as the aggregate and the preferred binder is a starch, acrylonitrile graft copolymer. For most cut live flowers and to avoid mold, the composition should be acidic, but not too acidic to break the bond, for example a pH down to about 5.5 for some binders is satisfactory; although a pH down to 4 and below for cut flowers is satisfactory so long as the binder's bond is not broken. If desired, a higher pH, for example up to about 8.5 can be used. Advantageously, the composition can be added to water in a container of any size or shape in an amount sufficient to form the bound aggregate and the composition sinks in and disperses throughout the water and forms a support without the need for mixing with a mixer or kneading with the hands. Advantages and representatives uses are set forth below.