Page 61 - Plastics News September 2023

TECHNOLOGY

Molecular Breakthrough Boosts Durability of Plastics

“The molecule not only solves current
issues but significantly opens up de-
sign space for more innovations in the
hen incorporated into plastics, deterioration is repeated exposure future,” said Dugger, a Sandia chemi-
Wthe molecule invented at Sandia from hot to cold temperatures and cal engineer who has been looking
Labs contracts instead of expanding back. Most materials expand when at potential applications, especially in
when exposed to heat by changing its heated and contract when cooled, defense systems.
shape. but each material has its own rate of The invention also can be incorporat-
Plastic typically expands and contracts change. Polymers, for example, ex- ed into different parts of a polymer at
when exposed repeatedly to hot and pand and contract the most, while different percentages for 3D printing.
cold temperatures, affecting its dura- metals and ceramics contract the “You could print a structure with cer-
bility in a range of applications. Addi- least. Complications ensue when sev- tain thermal behaviors in one area,
tives can mitigate this issue, but most eral materials are used in a product, as and other thermal behaviors in anoth-
products combine different materials, is often the case. er to match the materials in different
and managing fillers to compensate “Take for example, your phone, parts of the item,” Dugger said.
for thermal expansion mismatch gets which has a plastic housing, coupled
complicated. Researchers at Sandia to a glass screen, and inside that, the The molecule also has potential in
National Laboratories may have a so- metals and ceramics that make up the lightweighting applications and adhe-
lution — it all begins at the molecular circuitry,” Redline said. “These mate- sive formulations.
level. rials are all screwed, glued, or some- Currently, the molecule is only be-
The team modified a molecule so how bonded together and will start ing produced in small quantities — it
that it can easily be incorporated into expanding and contracting at different takes about 10 days to make between
a polymer to change its properties. rates, putting stresses on one another 7 and 10 grams.
When the molecule is heated, it con- which can cause them to crack or The team is working to reduce the
tracts instead of expanding by under- warp over time.” production steps using $100,000 in
going a change in its shape, explained “I thought, what if I conjured up a per- funding through Sandia’s technol-
research team leader Erica Redline, a fect material. What would that look ogy maturation program, which helps
materials scientist. like,” Redline said. ready products for the marketplace.
“When [the molecule is] added to a Redline thinks she’s done it, with the “My role is to see if there is an easier
polymer, it causes that polymer to help of her team: Chad Staiger, Jason way to make it at a commercial lev-
contract less, hitting expansion and Dugger, Eric Nagel, Koushik Ghosh, el,” said postdoc Eric Nagel. “There
contraction values similar to metals. Jeff Foster, Kenneth Lyons, Alana is nothing like it out there. I am re-
To have a molecule that behaves like Yoon and academic alliance collabo- ally excited at the possibilities of what
metal is pretty remarkable,” said Red- rators Professor Zachariah Page and this technology can do and the appli-
line. graduate student Meghan Kiker. cations that could be associated with
Reducing material deterioration Applications in 3D printing and light- this.”
One of the biggest factors in material weighting

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September 2023 PLASTICS NEWS