The choice of extrusion process is a decisive factor that affects the finished product quality for polybag manufacturing. One important component influencing the quality of the finished product is the selection of the extrusion technique. Two popular procedures that vary in the kind of dye used and the final product’s texture are cast film and blown film. In the horizontal extrusion moulding method known as “cast film”, heated resin is injected into a flat dye and allowed to cool on chill rolls. The film produced is clear, lightweight, and appropriate for lamination; its thickness varies based on the winding speed and the film is slower to crystallize and has less clarity but more durability because the resin molecules have reoriented, facing limitation of high wastage generation. This study primarily focused on the preparation of polybag film using the blown film extrusion process, utilizing high-quality polymer resins such as polyester polyethylene (PP) and linear low-density polyethylene (LLDPE) to minimize waste generation. The novelty of the process was reflected in minimising the waste generation. The control parameters considered in this study are temperature, pressure, and air intake volume. We investigated the influence of these critical process control parameters on the gauge thickness, optical properties, and mechanical strength of the polybag film produced through blown film extrusion. Additionally, we replicated the blown film process using simulation software developed at Pennsylvania College of Technology. The simulation results confirmed the overall stability of the polybag film produced through the blown film extrusion process.
References
[1]
Sikora, J.W. (2001) Experimental Research on the Blown Film Extrusion Process of Polyethylene. JournalofPlasticFilm&Sheeting, 17, 307-319. https://doi.org/10.1106/5tg5-y6bv-85u4-x40w
[2]
Graziano, A., Jaffer, S. and Sain, M. (2018) Review on Modification Strategies of Polyethylene/Polypropylene Immiscible Thermoplastic Polymer Blends for Enhancing Their Mechanical Behavior. JournalofElastomers&Plastics, 51, 291-336. https://doi.org/10.1177/0095244318783806
[3]
Dartora, P.C., Santana, R.M.C. and Moreira, A.C.F. (2015) The Influence of Long Chain Branches of LLDPE on Processability and Physical Properties. Polímeros, 25, 531-539. https://doi.org/10.1590/0104-1428.1732
[4]
Dutta, A. (1984) On Viscosity? Melt Flow Index Relationship. Rheologica Acta, 23, 565-569. https://doi.org/10.1007/bf01329290
[5]
Dobkowski, Z. (1986) Application of Melt Flow Index for Rheological Characterization of Branched and Linear Polymers. RheologicaActa, 25, 195-198. https://doi.org/10.1007/bf01332139
[6]
Cantor, K. (2018) Blown Film Extrusion. Carl Hanser Verlag.
[7]
Ilg, A.D., Price, C.J. and Miller, S.A. (2007) Linear Low-Density Polyoxymethylene versus Linear Low-Density Polyethylene. Macromolecules, 40, 7739-7741. https://doi.org/10.1021/ma702066y
[8]
Tremblay, B. (1992) Elongation Viscosity Estimates of Linear Low-Density Polyethylene/Low-Density Polyethylene Blends. PolymerEngineering&Science, 32, 65-72. https://doi.org/10.1002/pen.760320111
[9]
Saini, D.R. and Shenoy, A.V. (1983) Viscoelastic Properties of Linear Low Density Polyethylene Melts. EuropeanPolymerJournal, 19, 811-816. https://doi.org/10.1016/0014-3057(83)90151-9
[10]
Cran, M.J., Bigger, S.W. and Scheirs, J. (2005) Characterizing Blends of Linear Low-Density and Low-Density Polyethylene by DSC. JournalofThermalAnalysisandCalorimetry, 81, 321-327. https://doi.org/10.1007/s10973-005-0786-3
[11]
Belloli, D., Savaresi, S.M., Cologni, A., Previdi, F. and Cazzola, D. (2012) Modeling and Control of an Internal Bubble Cooling System. 2012 8thInternationalSymposiumonMechatronicsanditsApplications, Sharjah, 10-12 April 2012, 1-6. https://doi.org/10.1109/isma.2012.6215168
[12]
Butler, T.I. and Patel, R. (1993) Blown Film Bubble Forming and Quenching Effects on Film Properties. JournalofPlasticFilm&Sheeting, 9, 181-200. https://doi.org/10.1177/875608799300900303
[13]
Neubert, B., Dohm, C. and Wortberg, J. (2019) A New Scale-up/Scale-Down Method for the Blown Film Extrusion. AIP Conference Proceedings, Cancun, 10-14 December 2017, Article ID: 040001. https://doi.org/10.1063/1.5121659
[14]
Wagner Jr, J.R. (2012) Handbook of Troubleshooting Plastics Processes: A Practical Guide. John Wiley & Sons.
[15]
Chen, H.Y., Bishop, M.T., Landes, B.G. and Chum, S.P. (2006) Orientation and Property Correlations for LLDPE Blown Films. JournalofAppliedPolymerScience, 101, 898-907. https://doi.org/10.1002/app.23583
[16]
Dunning, D.J. (1982) Blown Film Production. In: Whelan, A. and Dunning, D.J., Eds., DevelopmentsinPlasticsTechnology—1, Springer, 75-153. https://doi.org/10.1007/978-94-009-6622-2_3
[17]
Wagner, J.R. (2016) Blown Film, Cast Film, and Lamination Processes. In: Wagner Jr., J.R., Ed., MultilayerFlexiblePackaging, William Andrew, 137-145. https://doi.org/10.1016/b978-0-323-37100-1.00010-7
[18]
Karttunen, A.T. and von Hertzen, R. (2011) Polymer Cover Induced Self-Excited Vibrations of Nipped Rolls. JournalofSoundandVibration, 330, 3959-3972. https://doi.org/10.1016/j.jsv.2011.03.016
[19]
Richards, H.A. (1962) Transportation Costs and Plant Location: A Review of Principal Theories. TransportationJournal, 2, 19-24.
[20]
Marini, J. and Bretas, R.E.S. (2017) Optical Properties of Blown Films of PA6/MMT Nanocomposites. MaterialsResearch, 20, 53-60. https://doi.org/10.1590/1980-5373-mr-2017-0280
[21]
Majumder, K.K., Ding, Y., Hobbs, G. and Bhattacharya, S.N. (2008) Prediction and Experimental Verification of Bubble and Processing Characteristics in Blown-Film Extrusion. JournalofAppliedPolymerScience, 111, 2657-2668. https://doi.org/10.1002/app.29219
[22]
Simpson, D.M. and Harrison, I.R. (1992) The Use of Deformation Rates in the Scale-Up of Polyethylene Blown Film Extrusion. Journal of Plastic Film & Sheeting, 8, 192-206. https://doi.org/10.1177/875608799200800304
[23]
Sun, Y. and Gupta, M. (2006) An Analysis of the Effect of Elongational Viscosity on the Flow in a Spiral-Mandrel Die. AdvancesinPolymerTechnology, 25, 90-97. https://doi.org/10.1002/adv.20061
[24]
Huang, C. (1998) A Systematic Approach for the Design of a Spiral Mandrel Die. PolymerEngineering&Science, 38, 573-582. https://doi.org/10.1002/pen.10220
[25]
Knittel, R. (1987) Blown Film Bubble Collapsing Improvement. Journal of Plastic Film&Sheeting, 3, 23-32. https://doi.org/10.1177/875608798700300104
[26]
Sidiropoulos, V., Tian, J.J. and Vlachopoulos, J. (1996) Computer Simulation of Film Blowing. JournalofPlasticFilm&Sheeting, 12, 107-129. https://doi.org/10.1177/875608799601200204
[27]
Muslet, I.A. and Kamal, M.R. (2004) Computer Simulation of the Film Blowing Process Incorporating Crystallization and Viscoelasticity. Journal of Rheology, 48, 525-550. https://doi.org/10.1122/1.1718500
[28]
Brown, S., Chance, F., Fowler, J.W. and Robinson, J. (1997) A Centralized Approach to Factory Simulation. Future Fab International.
[29]
Graul, M., Boydstun, F., Harris, M., Mayer, R. and Bagaturova, O. (2003) Integrated Framework for Modeling & Simulation of Complex Production Systems. Knowledge Based Systems, Inc.
[30]
Schumann, M., Bluemel, E., Schulze, T., Strassburger, S. and Ritter, K.C. (1998) Using HLA for Factory Simulation. Proceedings of the 1998 Fall Simulation Interoperability Workshop, Orlando.
[31]
Henriksen, J.O. (1997) An Introduction to SLX. Proceedings of the 29th Conference onWinter Simulation, Atlanta, 7-10 December 1997, 559-566. https://doi.org/10.1145/268437.268579
[32]
Gopura, R.A.R.C. and Jayawardane, T.S.S. (2012) Analysis, Modeling and Simulation of a Poly-Bag Manufacturing System. Engineering, 4, 256-265. https://doi.org/10.4236/eng.2012.45034
[33]
Most Reliable Shrouds, Polybag and Flexible Packaging Manufacturer for the Sri Lanka Apparel Industry. http://www.thermosl.com/
[34]
Products and Services. http://www.mathworks.com/products/
[35]
Wang, J. (2008) Process Bottleneck Analysis and Production Scheduling of Process Industry. Ph.D. Thesis, Tsinghua University.
