By using a self-designed pressure-jump apparatus, we investigated the melt solidification behavior in the rapid compression process for poly-ethylene-terephthalate (PET), polyether-ether-ketone (PEEK), isotactic polypropylene (iPP), high-density polyethylene (HDPE), and the living polymer sulfur. The experimental results clearly show that crystallization could be inhibited, and some melts were solidified to the full amorphous state for PET, PEEK, and sulfur. Full amorphous PEEK that was 24 mm in diameter and 12 mm in height was prepared, which exceeded the size obtained by the melt quenching method. The bulk amorphous sulfur thus obtained exhibited extraordinarily high thermal stability, and an abnormal exothermic transition to liquid sulfur was observed at around 396 K. Since the solidification of melt is realized by changing pressure instead of temperature and is not essentially limited by thermal conductivity, it is a promising way to prepare fully amorphous polymers. In addition, novel properties are also expected in these polymers solidified by the pressure-jump within milliseconds.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6403784 | PMC |
| http://dx.doi.org/10.3390/polym10080847 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Structure-Stability Relationships in Pt-Alloy Nanoparticles Using Identical-Location Four-Dimensional Scanning Transmission Electron Microscopy and Unsupervised Machine Learning.
ACS Nano
January 2025
Department of Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
Nanoparticulate electrocatalysts for the oxygen reduction reaction are structurally diverse materials. Scanning transmission electron microscopy (STEM) has long been the go-to tool to obtain high-quality information about their nanoscale structure. More recently, its four-dimensional modality has emerged as a tool for a comprehensive crystal structure analysis using large data sets of diffraction patterns.
View Article and Find Full Text PDFHigh-Aspect-Ratio InGaO Integrated with Amorphous AlO Nanofibers: All-Inorganic Self-Supporting Wearable Membranes for Ultralow-Concentration NO Sensing in Simulated Exhalation.
Nano Lett
January 2025
School of Optical and Electronic Information, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
Article Synopsis
- The study addresses challenges in creating flexible, breathable, and sensitive inorganic semiconductor gas sensors for wearable use in humid conditions.
- Researchers developed a self-supporting InGaO-AlO/AlO nanofiber membrane sensor using an innovative dual-spinneret electrospinning technique, featuring a unique bilayer structure.
- The resulting sensor is highly effective for detecting low concentrations of NO biomarkers (≈15 ppb) under breath-simulated conditions and maintains performance after extensive bending cycles, paving the way for advances in breath-based diagnostic applications.
Molecular insights into kinetic stabilization of amorphous solid dispersion of pharmaceuticals.
Phys Chem Chem Phys
December 2024
Department of Physical Chemistry, University of Chemistry and Technology Prague, Technická 5, CZ-166 28 Prague 6, Praha, Czech Republic.
Poor aqueous solubility of crystalline active pharmaceutical ingredients (APIs) restricts their bioavailability. Amorphous solid dispersions with biocompatible polymer excipients offer a solution to overcome this problem, potentially enabling a broader use of many drug candidate molecules. This work addresses various aspects of the design of a suitable combination of an API and a polymer to form such a binary solid dispersion.
View Article and Find Full Text PDFUnlocking the Ultrafast Deposition Kinetics within Bi-Tailored Core-Shell Structured Carbon Nanofibers for Highly Efficient and Ultrastable Sodium Metal Batteries.
Angew Chem Int Ed Engl
December 2024
School of Chemical Engineering, Sungkyunkwan University (SKKU), 2066, Seoburo, Jangan-gu, Suwon 440-746, Republic of, Korea.
Sodium metal anodes (SMA), featuring high energy content, low electrochemical potential and easy availability, are a compelling option for sustainable energy storage. However, notorious sodium dendrite and unstable solid-electrolyte interface (SEI) have largely retarded their widespread implantation. Herein, porous amorphous carbon nanofiber embedded with Bi nanoparticles in nanopores (Bi@NC) was rationally designed as a 3D host for SMA.
View Article and Find Full Text PDFHigh Entropy Oxide Duplex Yolk-Shell Structure with Isogenic Amorphous/Crystalline Heterophase as a Promising Anode Material for Lithium-Ion Batteries.
Small
November 2024
State Key Laboratory of Coordination Chemistry, Coordination Chemistry Institute, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China.
Article Synopsis
- Achieving precise composition and structure in high entropy materials is crucial for enhancing their energy storage capacity.
- A novel high entropy oxide, (CrMnFeCoNi)O, with a unique duplex yolk-shell structure was created using a simple reaction process, ultimately leading to an effective anode material for lithium-ion batteries.
- The resulting anode, DYSHEO-450, demonstrated impressive performance, achieving high charge capacities and excellent cycle stability, paving the way for further innovations in high-entropy materials.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!