BLOW-UP RATIOS EFFECT ON LLDPE FILMS PROPERTIES WITH DIFFERENT MATERIAL TYPES Bayu Krisnamurti, Mas Ayu Elita Hafizah, Azwar Manaf
Departement of Physics,Faculty of Mathematics and Natural Sciences. University of Indonesia. Depok, Indonesia
Abstract
This research explores producing high-impact LLDPE films for flexible packaging, focusing on the influence of the blow-up ratio (BUR) in the blown film extrusion process. LLDPE films with varying material grades were produced using a mini blown film extrusion process, with BUR systematically varied between 1.5 to 2.45. Standardized tests evaluated mechanical properties and thickness. The best sample, with material & ratio variation 1.3 and BUR 2.0 (LLDPE/Hexene Copolymer & Plastomer mixture), showed outstanding impact strength and tearing resistance among of the references sample and another material type & variation. Differential scanning calorimetry (DSC) analyzed thermal properties for optimal high-impact LLDPE films. The research also aims to identify optimal parameters for high-impact LLDPE films suitable for mono-material applications in flexible packaging. LLDPE outstanding mechanical and thermal properties have drawn attention across industries. A mini blown film extrusion process produced LLDPE films with varying material grades, while BUR ranged from 1.5 to 2.45. Mechanical properties, including tensile strength, elongation, Young modulus, impact resistance, tearing strength, and thickness, were evaluated. The best optimization sample achieved an impact strength of 2,808 J/mm2 with a 25% increase in outer/inner positions compared to references. Tensile strength values were 50/48 N/mm2 in MD/TD positions, with elongation reaching 870/825%. Secant Modulus was 100/55 in MD/TD positions, and thickness variations were observed across the BUR range. Tearing strength measurements resulted in 872/843 gram-forces in MD/TD positions, highlighting the best material and BUR combination LLDPE for flexible packaging. The research also investigated film sealing strength using the sealing initiation temperature (SIT), confirming excellent sealing integrity at lower temperatures. DSC analysis provided insights into thermal properties for creating High Impact LLDPE films in flexible packaging applications. In conclusion, this research identifies optimal parameters for high-impact LLDPE films, enhancing their suitability for flexible packaging applications and contributing to sustainability in the flexible packaging industry.
Keywords: Blow Up Ratio, Impact Strength, LLDPE, Flexible Packaging
