Skip to main content
Sister Publication Links
  • Rubber & Plastics News
Subscribe
  • My Account
  • LogIn
  • News
  • Technology Focus
    • Features
    • Technical Papers
    • Analysis: Rubber mixing plants of the future
      Analysis: US probes dumping by ESBR suppliers
      Opinion: Tire labels stuck in a rut
      Analysis: NR pricing takes one step forward, two steps back
    • Technical paper: Varying Si-substituents for rubber silanes
      White paper: Role of tire innerliners in improving 'in-use rolling resistance'
      White paper: Why tire air retention matters now more than ever
      Nippon Soda: Use of 1,2-polybutadiene in CSM rubber applications
  • Events
    • ERJ Events
    • ERJ Livestreams & Webinars
    • Industry Events
    • Journey to Automation Awards 2020
      Sustainability: Top 10 E4S projects table
  • Maps & Reports
  • People
  • Directory
  • Digital Edition
  • Brainiac
MENU
Breadcrumb
  1. Home
  2. News
August 15, 2017 12:00 AM

Harvard researchers advance self-healing rubber

Patrick Raleigh
  • Tweet
  • Share
  • Share
  • Email
  • More
    Print

    Harvard researchers advance self-healing rubber

    Cambridge, Massachusetts – Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new type of rubber that is as tough as natural rubber but can also self-heal, the Harvard University school has reported.

    In order to make a rubber self-healable, the team needed to make the bonds connecting the polymers reversible, so that the bonds could break and reform, explained a 14 Aug release.

    “Previous research used reversible hydrogen bonds to connect polymers to form a rubber but reversible bonds are intrinsically weaker than covalent bonds,” said Li-Heng Cai, a postdoctoral fellow at SEAS.  “This raised the question, can we make something tough but can still self-heal?”

    Cai, along with Jinrong Wu, a visiting professor from Sichuan University, China, and senior author David Weitz, Mallinckrodt professor of physics and applied physics, developed a hybrid rubber with both covalent and reversible bonds.

    The concept of mixing both covalent and reversible bonds to make a tough, self-healing rubber was proposed in theory by Cai but never shown experimentally because covalent and reversible bonds don’t like to mix.

    “These two types of bonds are intrinsically immiscible, like oil and water,” said Cai.

    The researchers developed a molecular ‘rope’ of randomly branched polymers to tie these two types of bonds together: allowing two previously unmixable bonds to be mixed homogeneously on a molecular scale. This, said Harvard, enabled the creation of a transparent, tough, self-healing rubber.

    “Typical rubber tends to crack at certain stress point when force is applied,” the SEAS release noted. “When stretched, hybrid rubber develops so-called crazes throughout the material, a feature similar to cracks but connected by fibrous strands.

    “These crazes redistribute the stress, so there is no localized point of stress that can cause catastrophic failure. When the stress is released, the material snaps back to its original form and the crazes heal.”

    Harvard’s office of technology development has filed a patent application for the technology and is actively seeking commercialisation opportunities, continued the release, adding that the self-healing ability is appealing for a wide variety of rubber products.

    “Imagine that we could use this material as one of the components to make a rubber tire,” said Wu. “If you have a cut through the tire, this tire wouldn’t have to be replaced right away. Instead, it would self-heal while driving enough to give you leeway to avoid dramatic damage.”

    But there is still much more to do, said Weitz, who is also director of Harvard’s materials research science and engineering center, co-director of the BASF Advanced Research Initiative, a member of the Kavli Institute for Bionano Science and Technology, and a core faculty member at the Wyss Institute for Biologically Inspired Engineering.

    “For materials science, it is not fully understood why this hybrid rubber exhibits crazes when stretched,” concluded Weitz. “For engineering, the applications of the hybrid rubber that take advantage of its exceptional combination of optical transparency, toughness, and self-healing ability remain to be explored.”

    RECOMMENDED FOR YOU
    Chemours ups sustainability efforts with new executive role
    Chemours ups sustainability efforts with new executive role
    Dates announced for virtual World Rubber Summit 
    Dates announced for virtual World Rubber Summit 
    Calender maker Comerio Ercole on a roll
    Calender maker Comerio Ercole on a roll
    Free Newsletters

    Breaking news and in-depth coverage of essential topics delivered straight to your inbox.

    Subscribe today

    Get the latest news impacting the European rubber industry, from breaking news to razor-sharp analysis, in print and online.

    Subscribe now
    Connect with Us
    • LinkedIn
    • Twitter
    • Youtube

    Logo
    Contact Us

    @ 2019 European Rubber Journal. 
    European Rubber Journal is published bi-monthly by NUERJ Ltd.

    Registered Office: Castle House, 89 High Street,
    Berkhamsted, Hertfordshire HP4 2DF, United Kingdom. 

    Tel. + 44 (0)203 196 0141 

    Registered No. 13104613 England

    Email: [email protected]

    Website www.european-rubber-journal.com

    Customer service 

    Tel. + 44 (0)203 196 0141 

     

    Resources
    • About us
    • Contact Us
    • Advertise with Us
    • Media Kit
    • Ad Choices Ad Choices
    • Sitemap
    Legal
    • Terms and Conditions
    • Privacy Policy
    • Privacy Request
    Copyright © 2021. NUERJ LTD. All Rights Reserved.
    • News
    • Technology Focus
      • Features
      • Technical Papers
    • Events
      • ERJ Events
      • ERJ Livestreams & Webinars
      • Industry Events
    • Maps & Reports
    • People
    • Directory
    • Digital Edition
    • Brainiac