WEB EXCLUSIVE: DSM Engineering Plastics, Birmingham, Mich., claims it has made a breakthrough in nylon 6 blown-film processing for flexible food packaging with the development of its new Akulon XS. Improved crystallization behavior of this new grade results in an extended processing window, which provides new opportunities in designing coextruded as well as monolayer film structures. DSM says processors are noticing significant improvements in production when using Akulon XS. The high crystallization rate of conventional nylon 6 can limit its processing window. Processors must either compromise on productivity, or obtain improved processability by blending in more expensive amorphous nylons or nylon copolymers.
Akulon XS crystallizes much slower in the film bubble than conventional nylon 6, matching the crystallization rate of other material layers. This creates a more stable bubble and gives processors more leeway in their processing conditions. Also, the film is said to be more stretchable, so less force is needed to achieve the same blow-up ratio, or the same force can be used to produce a bubble with a BUR between 7% and 10% higher. Fewer wrinkles in the flat film are also claimed.
Even through slower crystallization creates larger crystals that might be expected to produce a less clear film, tests on full-scale production lines have shown that there is virtually no discernible difference in the optical properties of films made with a benchmark film-grade nylon 6 and Akulon XS. DSM offers support to Akulon XS customers to optimize film structure designs, based on its DSM Film Structure Calculation Model. This model predicts the barrier properties of different film structures, even after retort processing, and enables blown film producers to find the optimal layer structure and processing conditions for Akulon XS.