Technology tip: Gels in polyethylene films
In the purest sense, a “gel” is a three-dimensional polymer network of sufficient crosslink density that prevents it from flowing. In practice, however, the term “gel” is also used to describe a variety of visual defects in films. Such defects can include crosslinked polymeric gels, non-crosslinked polymeric gels and nonpolymeric defects such as fibers, dust, additives and moisture. Nonpolymeric gels are typically introduced from external sources.