Keeping Cool With a Sodium Polyacrylate Ice Pack
Finding a reliable sodium polyacrylate ice pack in the back of your freezer is usually a lifesaver when you've tweaked your back or need to keep a lunch cool. We've all seen them—those squishy, gel-filled pouches that seem to stay cold forever without ever turning into a solid block of hard ice. But have you ever actually wondered what's going on inside that plastic film? It's not just "blue goo." It's actually a pretty clever bit of chemistry that makes our modern lives a whole lot easier. ...