Blending of High-Performance LLDPEs with Butene-LLDPEs and LDPEs

Several high-performance LLDPE resins for film applications have been developed in the past few years through Advanced Ziegler–Natta or Single-Site catalysts. These new resins significantly improve the film properties of conventional Ziegler–Natta resins, but they are generally more costly and/or more difficult to process. A relatively simple strategy for addressing the cost and processability issues is via post-reactor blending, either with butene-LLDPEs in order to reduce cost, or with LDPEs in order to improve processability. Blending of high-performance resins has a generally detrimental effect on film strength properties, although there are exceptions in certain compositions. Viability of a certain blend composition thus hinges on a cost versus performance evaluation of the properties of interest. The present work focuses on the performance aspect, through a study of the effect of blending butene-LLDPEs and LDPEs on the optical and mechanical properties of Advanced Ziegler–Natta and metallocene-LLDPEs.