Cambered and Non-flat Polyethylene Webs Induced by Thickness Variation

One of the most common web defects is web bagginess. Although it appears in most web materials, it is very difficult to categorize since its appearance changes from one case to the other; hence it has been given different definitions by different people. The most general way to define a baggy web is a web that does not lie flat/straight and has an intrinsic length difference across the width of the web. In this study, polyethylene webs were used as the main material to develop an understanding on some of the web bagginess cases through experimentation. Viscoelastic material properties behavior of polyethylene web was also characterized using time-temperature superposition. Digital image acquisition was used to detect web bagginess. With these results, it is now possible to correctly model this defect using a numerical simulation under development by the Web Handling Research Center.Mechanical & Aerospace Engineerin

WEBS INDUCED BY THICKNESS VARIATION

you will always be in my thoughts…. iii ACKNOWLEDGEMENTS In our lifetime, rarely we will encounter significant people who are willing to go the distance with us; to assist, to nurture life’s hard-earned lessons and most importantly to guide us through uncharted waters till we reached safe harbor. The important roles these people play, to whom we are always grateful. First and foremost, I will like to extend my deepest gratitude to my mentor, advisor and thesis chair, Dr. Hongbing Lu, for his insightful guidance, encouraging confidence and immeasurable kindness. To whom which without generous financial assistance, this thesis will never materialize. As well, my heartfelt appreciation goes to my other committee members Dr. J. Keith Good and Dr. Eric Price; for the encouragement, experimental equipments and invaluable trust. I will also like to take the opportunity to thank two most esteem authority in the field of web handling: Prof. Bruce Feiertag; for taking me into his wing as an apprentice and teaching me everything there is to know about web handling, and Prof. John Shelton; for helpful suggestions and valuable discussion, especially when I was stuck