@materiologist

Professor of Chemical, Biological, and Materials Engineering at @USouthFlorida. Research in #Polymers #SoftMaterials #Thermodynamics. Views are my own.

Joined February 2015
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Our new paper provides a new proposed leading-order understanding of why nanoparticles reinforce rubber, potentially addressing a 100-year mystery. @PolymerPolymath @EngineeringUSF @USFResearch pnas.org/doi/10.1073/pnas.25…

Glassy interphases reinforce elastomeric nanocomposites by enhancing volume expansion under strain...

For nearly a century, introduction of nanoparticles to elastomers has yielded extraordinarily tough nanocomposites that are critical to technologie...

pnas.org
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David S. Simmons retweeted
Gizmodo
@GizmodoApr 16
The formula for reinforced rubber is so effective that we've counted on it for nearly 100 years. But scientists had never reached a verdict as to why it works so well. gizmodo.com/after-100-years-…

After 100 Years, Engineers Finally Discover Why Rubber Is So Tough

Essentially, reinforced rubber fights against its own incompressibility.

gizmodo.com
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(the answer is no) read here: doi.org/10.1021/acs.macromol… feel free to DM if you cannot access! – at Philadelphia, PA
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Very excited about this new paper from our group (former student @_Drayerv2 ), on the origins of the molecular weight dependence of Tg. We think these findings will ultimate require the textbook understanding of this trend to be rewritten. lnkd.in/eAnpc2rj 🧵

LinkedIn

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lnkd.in
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At least one model, a substantial Tg dependence on molecular weight is observed even when the ends are dynamically identical to the interior. Even in models where a chain end effect is observed, its importance weakens on cooling such that it has little effect on Tg.
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These findings are inconsistent with chain end dilution models of the molecular weight Tg dependence. They suggest a need to reopen the problem of the Tg molecular weight dependence, with attention given to more modern theories of Tg and its dependence on molecular weight.
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Luke Landherr@danteshepherd26 Aug 2023
The Boston Globe printed my letter today:
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Tarak Patra@tarak_patra30 Apr 2023
Our new paper in @Nature with @sanatkk and @TomislavRovis, and Eugene Chen reports a new method that compatibilizes immiscible mixed plastics. So happy to contribute to this collaboration and excited about the future potential. nature.com/articles/s41586-0…
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Pre-print out! So proud of the culmination of my PhD work in this paper.
Douglas Tree@TreeSoftMatter24 Mar 2023
At #APSMarch, I gave a talk based on work by my former student @pierrekawak on simulations of low-T phase diagrams relevant for polymer crystallization. We now have a pre-print up: doi.org/10.26434/chemrxiv-20… We'd love any feedback or questions.
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Our new paper in @NaturePhysics, with K. Schweizer and A. Phan, reveals a signature of a combined caging and elasticity origin of the #glasstransition within dynamics at the surface of glass-forming liquids. Surface gradients have long-range tails! rdcu.be/c8jTu 🧵
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This finding provides compelling new support for the physics underlying the ECNLE model of glass formation. In essence, this long-range 1/z gradient is a direct signature of collective elastic physics within the ECNLE theory.
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The shorter-range gradient is of mixed nature, combining elastic effects with a gradient in segmental localization length scale. Our results thus point to a dual-barrier mechanism of glass-formation, with contributions from local caging and from long-ranged collective elasticity.
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