Scanning Small-Angle X-ray Scattering of Injection-Molded Polymers: Anisotropic Structure and Mechanical Properties of Low-Density Polyethylene
Journal article, 2023

Injection molding is known to create a layered anisotropicmorphologyacross the sample thickness due to varying shear and cooling ratesduring the manufacturing process. In this study, scanning small-angleX-ray scattering was used to visualize and quantify the distributionof hierarchical structures present in injection-molded parts of low-densitypolyethylene (LDPE) with varying viscosities. By combining scatteringdata with results from injection molding simulations and tensile testing,we find that oriented shish-kebab structures, as well as elongatedspherulite structures consisting of semicrystalline ellipsoids, contributeto high ultimate tensile strength along the flow direction. Furthermore,we show that a higher degree of orientation is found close to theinjection gate and in LDPE with higher viscosity, consequently fromelevated shear and cooling rates present during the injection moldingprocess.

morphology

computational modeling

scanning SAXS

polyethylene

mechanical performance

Author

Linnea Björn

Chalmers, Physics, Materials Physics

Renan Melhado Mazza

Tetra Pak

Eskil Andreasson

Tetra Pak

Fredrik Linell

Tetra Pak

Viviane Lutz-Bueno

Paul Scherrer Institut

Manuel Guizar-Sicairos

Paul Scherrer Institut

Elin Persson Jutemar

Tetra Pak

Marianne Liebi

Chalmers, Physics, Materials Physics

ACS Applied Polymer Materials

26376105 (eISSN)

Vol. 5 8 6429-6440

Subject Categories

Polymer Chemistry

Polymer Technologies

DOI

10.1021/acsapm.3c01007

More information

Latest update

3/7/2024 9