Researchers make it easier to squirt out the last of the shampoo with science


If you’ve ever gnawed your way through a plastic bottle to get out the last delicious drops of soap you’ll be pleased to learn that researchers at The Ohio State University have created a type of plastic containing small structures that “cradle the droplets of soap aloft above tiny air pockets.” In other words, the soap never touches the bottle so it never sticks.

The “structures are built up using much smaller nanoparticles made of silica, or quartz—an ingredient in glass—which, when treated further, won’t stick to soap,” wrote the researchers.

The material can actively repel soaps and shampoos and allows you to shake and squeeze out the last drops of washing liquid. The problem wasn’t easy to solve. Because soap is a surfactant the researchers had to discover a way to create a surface to repel a surfactant.

“It’s what you’d call a first-world problem, right? ‘I can’t get all of the shampoo to come out of the bottle.’ But manufacturers are really interested in this, because they make billions of bottles that end up in the garbage with product still in them,” said Bharat Bhutan, a professor at OSU.

The bottles are environmentally friendly and can be recycled normally. The structures look like “shaggy heart-shaped pillows” and are hard as glass. The product can actually improve recycling because the bottles do not have to be rinsed clean. Instead, they can be simply shaken to get out the last drops of sweet, sweet shampoo. The technology could also help other plastic objects – like car headlights – repel nasty materials and may help you get out the final portion of fancy face cream or expensive dandruff-control conditioner.