However, a great deal of work is needed in order to realize this potential. For example, the waste management industry and plastics manufacturers need to learn from one another. The recyclers often don’t realize what standards industries set for possible recycled materials, and the plastics manufacturers don’t understand the problems that recycling involves. For one thing, it’s difficult to sort the different kinds of plastics out of piles of waste. As a result, the recycled materials that are available today are of lower quality than their pure original versions. For example, if the widely used plastics polyethylene (PE) and polypropylene (PP) are mixed together, the original materials lose their durability.