Additive-like amounts of HDPE prevent creep of molten LDPE: Phase-behavior and thermo-mechanical properties of a melt-miscible blend
Journal article, 2017

Low-density polyethylene (LDPE) is the preferred type of polyolefin for many medical and electrical applications because of its superior purity and cleanliness. However, the inferior thermo-mechanical properties as compared to, for example, high-density polyethylene (HDPE), which arise because of the lower melting temperature of LDPE, constitute a significant drawback. Here, we demonstrate that the addition of minute amounts of HDPE to a LDPE resin considerably improves the mechanical integrity above the melting temperature of LDPE. A combination of dynamic mechanical analysis and creep experiments reveals that the addition of as little as 1 to 2 wt% HDPE leads to complete form stability above the melting temperature of LDPE. The investigated LDPE/HDPE blend is found to be miscible in the melt, which facilitates the formation of a solid-state microstructure that features a fine distribution of HDPE-rich lamellae. The absence of creep above the melting temperature of LDPE is rationalized with the presence of tie chains and trapped entanglements that connect the few remaining crystallites.

thermo-mechanical properties

creep

miscible polyethylene blend

tie chains

phase behavior

Author

Mattias Andersson

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Polymer Technology

Jonna Hynynen

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Polymer Technology

Mats Andersson

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Polymer Technology

Per Ola Hagstrand

Innovation and Technology

Thomas Gkourmpis

Innovation and Technology

Christian Müller

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Polymer Technology

Journal of Polymer Science, Part B: Polymer Physics

0887-6266 (ISSN) 1099-0488 (eISSN)

Vol. 55 2 146-156

Subject Categories

Chemical Sciences

DOI

10.1002/polb.24262

More information

Latest update

9/6/2018 2