Why Some Materials Cannot Be Recycled Together
Launch library · evergreen read
Different materials melt, break down or react at different temperatures and under different chemical conditions, which means mixing them during reprocessing usually ruins the batch rather than simply blending it. A small amount of the wrong plastic type mixed into a batch of another can weaken the finished product significantly.
Glass is a particularly clear example: a small amount of ceramic or heat resistant glass mixed into a batch of bottle glass can create weak points in the finished product, since these materials melt at different temperatures and do not bond properly with standard container glass once cooled and reformed.
This is why sorting facilities invest heavily in separating materials by type before reprocessing even begins, rather than relying on later stages to fix mixing problems. Once contamination happens at the material level, rather than just the bin level, there is often no practical way to separate it back out again.