PP, #5
Like a lot of other types of plastic on this list, polypropylene (designated by the number 5) can be recycled—but it depends a lot on what its final form is. In terms of household items, PP is used to make various food containers (like for yogurt and rotisserie chicken), some kinds of pill bottles, and plastic straws.
The market for polypropylene got shaken up in recent years after China, which used to be one of the main markets for much of the U.S.’s recycled plastic, stopped importing plastic from overseas in 2018. Despite the widespread popularity of polypropylene, Greenpeace has calculated that less than a third of the U.S. population has access to a recycling system that will accept these plastics.
There are some key problems plaguing recycled polypropylene materials, including lingering smells from stinky container ingredients (gasoline, yogurt) and the fact that the recycled version often comes out an unappealing gray or black color, making it unsuitable for consumer products. Recent innovations have shown some promise in solving these problems, which could mean more uses for the recycled material.
