These include a new solution for reducing lactam pollution in BOPA film production and in co-extrusion of PA6 outer layer(s), and a breathable, cost-effective film to replace highly polluting cellulose in smoked meat applications.
DSM Engineering Plastics has introduced a low oligomer polyamide (LOPA), following successful trials that showed a marked reduction in lactam pollution. LOPA is an upgraded polyamide (PA) material with a lower C1 monomer count. Compared to conventional PA6 at a viscosity of RSV 3.0, which has a C1 level of about 0.18 percent, LOPA has a significantly lower level of about 0.10 percent. DSM launched LOPA in June 2010.
Production of bi-axial oriented polyamide (BOPA) film using conventional polyamide 6 (PA6) resins leads to significant pollution by lactams, which are internal (cyclic) amides. Lactams evaporate and condense in the form of a fine, white powder that adheres to equipment, walls and ceilings, and is easily transported through the air where it can be inhaled by workers. The cause of this evaporation is high C1 (caprolactam) content in the PA6 resin.
BOPA film is used for flexible packaging, particularly food packaging, because it provides excellent protection from deterioration. A typical BOPA film line can produce up to 15 tons of lactams per year. This ubiquitous powder requires frequent cleaning of stretching ovens and the overall production facility, which is costly and disruptive. More importantly, it may pose a health risk to workers due to ongoing inhalation of the material into the lungs. Finally, production of lactams has a negative impact on air quality and can contribute to overall environmental degradation.
While many BOPA converters had become resigned to lactams as an inconvenientbut unavoidable byproduct of film production, DSM Engineering Plastics took the initiative to develop a better polyamide material that could reduce lactams and solve a latent industry need.
According to customers’ feedback during DSM film event in June 2010, BOPA converters are impressed that DSM took a proactive approach to a chronic industry problem and was able to engineer a high-performance material with a lower
The casings used to produce sausage, ham, cheese and other smoked items must be permeable so that smoke can reach the food to impart flavor and color. Currently, natural gut, collagen and cellulose are the primary materials used for smokable casings. A new smokable casing solution with better environmental performance and a lower price was needed, however, polymeric casings historically have not been used, due to a lack of permeability.
DSM Engineering Plastics has combined its understanding of the specific needs of customers, and applied its expertise, to combine highly breathable Arnitel VT (vapour transmission) with Akulon polyamide 6 (PA6) resin in a patented solution for new smokable casings. These enable customers to avoid the serious environmental issues of cellulose whilst at the same time offering significant cost savings.
The addition of up to 40 percent Arnitel VT increases the permeability of Akulon significantly, enabling smoke to pass through the casing to reach the sausage or ham inside. In some cases, smoked food production can be simplified from three steps to one, with higher quality, due to the excellent smoke transmission of the polymer.
At the same time, Arnitel VT, which is a monolithic technology without micropores or perforations, provides a highly protective barrier against oxygen and other contaminants for safety and long shelf life of the food.
According to Paul Habets, Global Segment Manager DSM Engineering Plastics, several customers have adopted this unique blend of materials to manufacture smokable casings for bacon and sausage: “The Arnitel VT/Akulon solution is helping them provide a more price-competitive casing product and even target new market sectors which were traditionally dominated by cellulose casings.”