Metallocene polyolefins (mPOs) are increasingly gaining ground in adhesive applications due to their unique characteristics, supply security and enhanced performance in different fields. However, these materials also have their limitations and, in certain formulations, their applicability is a concern that manufacturers find difficult to overcome.
Most tackifying resins for adhesives have good compatibility with the traditional polymers that have been used for decades. These materials are relatively polar, which makes them work well with a range of raw materials. In contrast, metallocene polyolefins are completely different and, due to the PE and PP base, such structures tend to be non-polar. This property has a great impact on compatibility; therefore, when it comes to mPOs, the choice of resins is limited. MPOs work well with non-polar resins (i.e., aliphatic hydrocarbon resins), but they tend to be incompatible with natural-based resins that are more polar tackifiers.