Polymer foam material, device and use

A method for manufacture of a flexible hydrophilic polyurethane foam porous matrix comprising two matrix faces and therebetween a structural matrix framework defining a network of cells, having a cell network surface and therein a network of pores and a powder charge comprising at least two additives loaded in said structural matrix framework, said method comprising:

• providing an isocyanate phase and an aqueous phase making up a foamable polymerisable system;
• providing one or more slurry phase or solid concentrate of said powder charge, or insoluble portion thereof, making up said isocyanate phase or part thereof;
• and
• intimately admixing said isocyanate phase and said aqueous phase with reaction and foaming thereof;
• wherein the one or more slurry phase or solid concentrate makes up a part of one of said phases, said method comprises prior to, simultaneously with, or subsequent to admixing the other part thereof with the other phase thereof, or admixing said phases, combining the one or more slurry phase or solid concentrate with the other part thereof or with one or both of said phases;
• wherein the powder charge retains solid form after polymerization of the flexible polyurethane material and the powder charge is homogeneously distributed within the flexible hydrophilic polyurethane foam porous matrix;
• wherein a first additive comprises silver salt;
• wherein a second additive comprises an absorbent additive that retains a capacity for aqueous absorption properties of the powder charge;
• and
• wherein the flexible polyurethane material provides an accumulated release of approximately 1.2 mg/cm2 to 1.8 mg/cm2 of the silver salt into 50 mL of aqueous media over a period of 7 days or more.