Abstract
The development of new polymer composites is highly dependent on the design of novel fillers that can bring more benefits in the design and control of structure-property-function than conventional solid particles. Here, inspired by the unique coupling structures of tough mussel byssus, we employ nanodroplets of high-boiling-point oligomers as the liquid filler to fabricate a new class of polymer-droplet composites (PDCs). The combination of nanodroplets and chain end/tail modifier in PDCs finally generates soft-coupling structures with chain ends coupled by the nanodroplets. With this strategy, brittle poly(lactic acid) is successfully transformed into a tough bioplastic with toughness improved by over 2000% via a minimal amount of the modifiers (1.5 wt %). Moreover, the composites show unexpected speed-enhanced energy absorption capability. A soft-coupling toughening mechanism is further proposed for the first time to understand the PDCs' mechanical properties. This work also indicates the potential of nanodroplets as a new tool for tuning the mechanical properties and even functions of polymer composites.
| Original language | English |
|---|---|
| Pages (from-to) | 4568-4576 |
| Number of pages | 9 |
| Journal | Macromolecules |
| Volume | 53 |
| Issue number | 11 |
| DOIs | |
| State | Published - Jun 9 2020 |
Funding
This research is sponsored by the Technology Innovation Program of Oak Ridge National Laboratory and the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under Contract DE-AC05-00OR22725 with UT-Battelle, LLC. The authors thank Dr. Yuzhan Li for his assistance with 2D SAXS testing, Dr. Ryan S. Ginder and Dr. Phillip F. Britt for helpful discussions, and Dr. Kunlun Hong for access to gel permeation chromatography measurements. Gel permeation chromatography and electron microscopy of this research were conducted at the Center for Nanophase Materials Sciences (CNMS), which is a DOE Office of Science User Facility. This manuscript has been authored by UT-Battelle, LLC, under Contract DE-AC05-00OR22725 with the U.S. Department of Energy. The U.S. government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript or allow others to do so, for U.S. government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ).