AFFINITY™ Polyolefin Plastomers for blown film - Dow Specialty Packaging & Films - #1

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Processing Overview AFFINITY™ Polyolefin Plastomers (POPs) shear process similar to LLDPE and ULDPE, but with improved bubble stability, blow-up-ratio response, and gauge control. Resin Selection Choice of resin comonomer content (density) will largely dictate the melt profile and cooling requirements. High comonomer content resins have significantly lower melting and freezing points than LLDPE or ULDPE resins with similar density. Melt Index 0.5-3.0 g/10 min – best suited for monolayer fabrication 1-5 g/10 min – best suited for coextrusion Extruders L/D 24-32:1 L/D with comparable results to LLDPE Barrel Cooling Suggested with control within ±1°C Gear Boxes/DC Drives Sized for LLDPE extrusion Horsepower »5 lb/hr/hp (1.38 kg/hr/kw) Screw Choice/Operation Single flight and “moderate-work” barrier screws. Melt Flow Characteristics Similar to LLDPE of same melt index Pumping Efficiency Similar to LLDPE of same melt index Melt Quality Similar to LLDPE of same melt index Amps Slightly lower than LLDPE of same melt index Back Pressure Slightly lower than LLDPE of same melt index Dies and Blow-Up Ratios Blown film dies of low-pressure design are suggested. AFFINITY POPs show more response to drawdown and BUR. Die Gaps 30-120 mils (0.75-3.0 mm) BUR 1.8:1 to 4:1 Temperature Profile Standard “feed to meter” ramp-up with care taken not to pre-melt in feed zone. Feed Zone 280-325°F (138-163°C) Desired Melt Temperature 375-450°F (190-232°C) Bubble Cooling Frost line control is enhanced with dual-lip or multiple air rings and internal bubble cooling. AFFINITY POPs exhibit decreased sensitivity to melt fracture and produce smooth extrudates at lower melt temperatures. Handling/Processing Review current Material Safety Data Sheet (MSDS) included in Considerations every order. Blown Film Processing of AFFINITY™ Polyolefin Plastomers ®™Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow 1 of 2 Processing Guide