Abstract: A method and apparatus for the preparation of thermosetting foam products on a substantially continuous basis, and wherein the products are characterized by uniformity of formulation, dimensional accuracy, and dimensional stability. The invention contemplates the utilization of an extruder which receives raw, partially or fully expanded resin and fillers or additives at inlets thereof, with initial expansion occurring within the confines of the extruder. The initially expanded resin is passed through a first expansion chamber with an intermediate expansion zone therein, with the outlet from the first expansion chamber being modestly constricted. From the first expansion chamber, the partially or fully expanded resinous product is moved through a second expansion chamber wherein the intermediate zone is enlarged, so as to permit substantially full expansion of the resinous material therewithin.

Abstract: Hydrophilic floral display foam blocks are prepared from frothed urea-formaldehyde, and wherein the urea-formaldehyde contains an alkyl-aryl sulfonate, and wherein the alkyl-aryl sulfonate has been exposed to an aqueous solution of a quaternary ammonium salt in an amount sufficient to provide at least equal molar concentrations of the quaternary ammonium salt to the alkyl-aryl sulfonate present in the foam. The urea-formaldehyde foam may also contain quantities of sodium molybdate to enhance the stability and lifetime of cut flowers retained in the foam material. Also, the urea-formaldehyde foam may contain starch to help suppress the free formaldehyde odor and help increase the biodegradability of the cured foam. The resulting foam is hydrophilic in nature, and hence is readily wetted, with the hydrophilic characteristic not adversely affecting the life of cut flowers retained therein.