What materials are used to make an ice pack?

The simplest ice pack can be made using a plastic bag, such as a Ziplock bag, filled with crushed or cubed ice. An alternative homemade solution is a gel ice pack. Gel ice packs can be made using two cups of water and one-third cup of vodka in a freezer bag. Once these ingredients are added to the bag, it is recommended to seal and enclose it in an additional freezer bag, and then placing it in the freezer until frozen. The Watersorb website also sells Sodium polyacrylate as an alternative to an alcohol-water solution. Sodium polyacrylate should be used as one teaspoon per quart of water.