Application of Dynamar™ polymer processing additives in film manufacture significantly facilitates its production and gives perfect consumer properties to products
Best assistant to a processor
Dynamar™ processing additives designed and manufactured by 3M Company - the leading supplier of fluoropolymers and special additives - are widely applied in production of wares from polyethylene, polypropylene and other polymers.
Dynamar™ additives are of a fluoropolymer nature. Their activities lie in generation of a thinnest slip-layer between the melt and extruder walls in high shear load zones. As a result, pattern of polymer melt flow changes, melt flow index increases and surface defects of a product are corrected. Application of Dynamar™ additives gives another essential advantage - removal or significant reduction of carbon deposit, as well as decrease in time of film colour changeover.
How efficient application of Dynamar™ additives is can be shown on example of single-layer film production by blow hose extrusion method (clearance gap 0.6 mm) from LDPE and LLDPE composites (LDPE MFR 0.9, density 0.920; LLDPE MFR 0.8, density 0.925), containing 6% of TiO2. Dynamar™ FX5911X additive was used at concentration 0.05%.
Application of processing additive, infused as a concentrate, enabled to reduce the melt temperature during extrusion process due to efficient decrease in shear load on a polymer, that means due to increased melt flow index. It also helped to prevent surface defects, such as "sharkskin". Decreased processing pressure had a considerable influence on productivity of the process. Besides, the polymer processing additive enabled to improve surface appearance of finished goods.
Say No to sharkskin!
Impact of Dynamar™ processing additive on working melt temperature is shown in picture 1. The blue line features parameters of composite processing using Dynamar™ FX5911X additive, the red line - processing without this additive. As we can see, application of Dynamar™ additive allows to lower polymer processing temperature approximately by 15 degrees, which reduces the risk of carbon and defect formation in a product.
Another line chart (picture 2) reflects impact of Dynamar™ processing additive on pressure within an extruder by constant output and temperature. The red line recreates the initial stage of the experiment before application of polymer additive; the blue line represents the results obtained owing to use of polymer additive. As we can see, application of FX5911X processing additive at concentration of 0.05% allows to reduce melt pressure during extrusion process. As a result, it brings about productivity gain.
With the help of Dynamar™ additive one can significantly improve surface properties of film. A micrograph traces substantially increased smoothness of film surface and removal of a "sharkskin" defect. Moreover, application of Dynamar™ enables to manufacture films of more homogeneous thickness.
Dynamar™ processing additives allow to process polymers the way as if they had a lower melt viscosity rate. The line chart (picture 4) reflects indices of effective viscosity of high-molecular HDPE (MFR 3 (21.6 kg, density 0.950) and reduction of effective viscosity due to introduction of 0.07% of Dynamar™ FX5911X additive. Without this polymer processing additive "sharkskin" defect occurs at shear rate about 200 sec. -1. Infusion of the additive at concentrate of 0.07% increased this index up to 1000 sec. -1, which brought it to shear rate typical for HDPE with melt flow index 10. For reference the line chart (picture 4) presents rheological properties of a polymer with melt flow index 10.
Efficiency by any application
Thus, application of Dynamar™ polymer additives gives processors an opportunity to use for their products polymers with higher mechanical properties, possessing lower melt flow index and higher viscosity rate - without any problems aroused during processing of such polymers.
Application of Dynamar™ FX5911X polymer processing additive helped to obtain the following positive results:
- to prevent carbon formation;
- significantly to reduce number of gels formed;
- to increase output capacity by 20%;
- to improve outward appearance of wares, to enhance surface smoothness;
- to lower melt temperature in processing, which enables to diminish the smell of "burning" polyethylene and film;
- to improve control over the products thickness, as a result to reduce material consumption of production;
- to reduce processing pressure;
- to cut down time of colour changeover.
Dynamar™ polymer processing additives are also efficient in other extrusion processes, such as manufacture of various containers by blow extrusion method, production of fiber, tubes, cables, extrusion profiles.
Dynamar™ additives are introduced by polymer compounds manufacture or at the processing stage in the concentrate form; they are permitted for usage in production of packaging coming in touch with food products.
JSC 3M Russia invites for cooperation polymer compounds producers, concentrate producers, as well as processors interested in application of Dynamar™ additive concentrates.