TY - THES

T1 - An investigation on parameters influencing the properties of machine direction oriented polyethylene films

AU - Klobasa, Johanna

N1 - embargoed until 21-08-2024

PY - 2019

Y1 - 2019

N2 - The present work focuses on developing fundamental understanding around the property evolution process when a PE-based film is subjected to selective Machine Direction Orientation (MDO). The main objective is to provide a series of design guidelines for MDO-structures starting with their simplest building blocks, the monolayers, which subsequently make part of much more complex co-extruded structures. Of particular interest are stiffening effects observed in both machine and cross direction as well as improvement in optical properties such as haze and gloss, all of the above as a function of resin architecture and processing, specifically stretching conditions. The study relies on data sets generated with help of two lab scale MDO-units as well as several OEMs which are active in MDO process equipment manufacturing. The first part summarizes extensive analyses on a broad selection of carefully chosen MDO monolayer structures produced and stretched under similar conditions for optimum comparability. Special emphasis is given to mapping of “stretchability” broadly defined as operating window of temperature and stretching ratios a given material is able to withstand and its resulting properties. In a second step applicability of the findings to multilayer structures is investigated.

AB - The present work focuses on developing fundamental understanding around the property evolution process when a PE-based film is subjected to selective Machine Direction Orientation (MDO). The main objective is to provide a series of design guidelines for MDO-structures starting with their simplest building blocks, the monolayers, which subsequently make part of much more complex co-extruded structures. Of particular interest are stiffening effects observed in both machine and cross direction as well as improvement in optical properties such as haze and gloss, all of the above as a function of resin architecture and processing, specifically stretching conditions. The study relies on data sets generated with help of two lab scale MDO-units as well as several OEMs which are active in MDO process equipment manufacturing. The first part summarizes extensive analyses on a broad selection of carefully chosen MDO monolayer structures produced and stretched under similar conditions for optimum comparability. Special emphasis is given to mapping of “stretchability” broadly defined as operating window of temperature and stretching ratios a given material is able to withstand and its resulting properties. In a second step applicability of the findings to multilayer structures is investigated.

KW - Machine direction orientation

KW - MDO

KW - Polyethylene

KW - Flexible packaging

KW - PE

KW - Films

KW - Verstreckung

KW - Machine direction orientation

KW - MDO

KW - Polyethylen

KW - PE

KW - Flexible Verpackungen

KW - Folien

M3 - Master's Thesis

ER -