Tearing properties, crystallization behavior, microstructure, and morphology of LLDPE with different short branched chain distributions

Yi Ren; Wenjun Shao; Ying Wang; Li-Zhi Liu

doi:10.1515/ipp-2023-4432

Article

Tearing properties, crystallization behavior, microstructure, and morphology of LLDPE with different short branched chain distributions

Yi Ren , Wenjun Shao , Ying Wang and Li-Zhi Liu

Published/Copyright: October 30, 2024

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From the journal International Polymer Processing Volume 39 Issue 5

Abstract

The length and distribution of comonomers with short-chain branching (SCB) have a significant influence on the crystallization behavior and crystal structure of polymers, as well as the mechanical properties of the material. This study investigates the crystallization behavior and properties of linear low-density polyethylene (LLDPE) samples with similar density, molecular weight, and branching degree but varying SCB distributions. The results show that LLDPE with butene as the comonomer has a stronger ability to suppress crystallization compared to LLDPE with hexene as the comonomer due to its more uniform SCB distribution. Additionally, among LLDPEs with comonomers of octene, hexene, and butene, the LLDPE with the most uniform SCB distribution exhibits the weakest crystallization ability. Small-angle X-ray scattering (SAXS) and scanning electron microscopy (SEM) results indicate that LLDPE with more uniform distribution of SCB has smaller long-period and more regular lamellar structure. Therefore, LLDPE with more uniform SCB distribution exhibits weaker inhibition ability towards crystallization, leading to less agglomerated phases and weaker phase separation, resulting in higher tear strength.

Keywords: short-chain; LLDPE; crystal behavior; lamellar structure; comonomers

Corresponding author: Li-Zhi Liu, Advanced Manufacturing Institute of Polymer Industry, Shenyang University of Chemical Technology, Shenyang, 110142, China, Email: violetlj@yahoo.com

Research ethics: Not applicable.
Informed consent: Not applicable.
Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Competing interests: The authors state no competing interests.
Research funding: None declared.
Data availability: The raw data can be obtained on request from the corresponding author.

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Received: 2023-08-21

Accepted: 2024-01-06

Published Online: 2024-10-30

Published in Print: 2024-11-26

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Articles in the same Issue

https://doi.org/10.1515/ipp-2023-4432

Keywords for this article

short-chain; LLDPE; crystal behavior; lamellar structure; comonomers