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Title: Continuous one-pot melt extrusion approach for high-density polyethylene-based vitrimers
In this presenation, I will discuss a continuous melt extrusion approach in one go for the synthesis of high-density polyethylene (HDPE)-based vitrimers. Vitrimers are produced with two grafting two agents, with maleic anhydride serving as a reactive agent to facilitate crosslinking while dimethyl maleate helped to lower the surface energy for better maleation. This improved property is reflected in the 2 wt% system, where the crosslinking density had doubled and enhanced the stiffness of the material. Overall, these vitrimers had enhanced tensile stress at break and impact resistance as compared to that of HDPE, while yet having a similar melting temperature and tensile stress at yield. The crystallinity of the polymers decreased and thus these materials may be strong candidates for 3D printing applications as they are less susceptible to the warping issues that are encountered with unmodifed HDPE. These vitrimers are reprocessable with torque pf ~ 30 Nm, and thus they can be readily recycled despite the crosslinking of layers which imparts them with better mechanical and thermal properties.  more » « less
Award ID(s):
2044877
PAR ID:
10524733
Author(s) / Creator(s):
Publisher / Repository:
ACS
Date Published:
ISSN:
3928296
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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