A rigid open-cell plastic foam body useful, for example, as a filter is prepared by mixing equal parts of a diglycidal ether of bisphenol A epoxy resin and the reaction product of an excess of a polyfunctional amine and a polyfunctional fatty acid with two parts of water while avoiding the entrapment of air in the mixture to form an emulsion in which water is the continuous phase, casting the emulsion in the desired form and curing the emulsion.
Disclosed is a method of producing a porous material having open pores, comprising the steps of preparing a slurry from a mixture comprising a bisphenol-type epoxy resin, a specific mixture amide compound as a hardener, a filler and water, casting the slurry in a water-impermeable mold, hardening the slurry while it contains the water and dehydrating the hardened body.
Stable aqueous emulsions of epoxy resins containing as an emulsifying agent between 2 and 10% by weight relative to the weight of the epoxy resin of ethylene oxidepropylene oxide block polymers having the formulae and in which X is an integer of at least 8 and at most 22, Y is an integer from at least 25 and at most 40, and R is a radical of the group consisting of alkenyl, aralkyl, cycloalkyl, aralkenyl and cycloalkenyl radicals.
A coating formulation for making a porous coating on a laboratory apparatus is provided. The formulation comprises 100 parts by weight hardenable resinous material, and from about 0.1 to about 50 parts by weight blowing agent based on the 100 parts by weight resinous material. The resinous material has a hardening time which is sufficiently short such that gas generated by the blowing agent is entrapped within the resinous material. The coating formulation is hardenable upon application to a surface of a laboratory apparatus to form a porous coating which is used for marking purposes or for the retention of biological samples. Methods of retaining a biological sample on a coated laboratory apparatus having a surface made of the coating formulation are also provided.
A coating formulation for making a porous coating on a laboratory apparatus is provided. The formulation comprises 100 parts by weight hardenable resinous material, and from about 0.1 to about 50 parts by weight blowing agent based on the 100 parts by weight resinous material. The resinous material has a hardening time which is sufficiently short such that gas generated by the blowing agent is entrapped within the resinous material. The coating formulation is hardenable upon application to a surface of a laboratory apparatus to form a porous coating which is used for marking purposes or for the retention of biological samples. Methods of retaining a biological sample on a coated laboratory apparatus having a surface made of the coating formulation are also provided.
