Polymers
Supramolecular “Velcro” aids underwater adhesion
February 22, 2013 8:50 am | News | CommentsWhen gluing things together, both surfaces usually need to be dry. Gluing wet surfaces or surfaces under water is a challenge. Korean scientists have now introduced a completely new concept. They were able to achieve reversible underwater adhesion by using supramolecular "Velcro".
New imaging device is flexible, flat, and transparent
February 20, 2013 12:20 pm | News | CommentsA research team in Austria has developed an entirely new way of capturing images based on a flat, flexible, transparent, and potentially disposable polymer sheet. The new imager, which resembles a flexible plastic film, uses fluorescent particles to capture incoming light and channel a portion of it to an array of sensors framing the sheet. With no electronics or internal components, the imager’s elegant design makes it ideal for a new breed of imaging technologies.
Photo-growth of pores in a polymer gel network
February 7, 2013 9:08 am | News | CommentsResearchers at the Massachusetts Institute of Technology have pioneered a new method for producing polymer gels with tailored mechanical properties. The approach, which depends on the use of ultraviolet to break chemical bonds and prime them for new connections, could be used to make new materials that physically grow towards a light source in order to optimize their properties.
Stronger than Kevlar, light as a tee-shirt
February 4, 2013 8:52 am | by Angela Herring, Northeastern University | News | CommentsTraditionally, carbon fibers are made by “carbonizing” a polymer called poly-acrylonitrile, or PAN, by spinning it into a fiber and heating to form a homogenous carbons structure. Since its invention, improvement have been incremental, and version made with 100% carbon nanotubes are extremely expensive. A researcher at Northeastern University is working on a much cheaper, and stronger, alternative.
Exotic chemical compound could be useful in batteries
January 24, 2013 2:08 pm | News | CommentsNorthwestern University graduate student Jonathan Barnes had a hunch for creating an exotic new chemical compound, and his idea that the force of love is stronger than hate proved correct. He and his colleagues are the first to permanently interlock two identical tetracationic rings that normally are repelled by each other. Many experts had said it couldn't be done.
New antimicrobial hydrogels fight superbugs and drug-resistant biofilms
January 24, 2013 8:20 am | News | CommentsBacterial biofilms, which diseased groupings of cells found in 80% of infections, are a significant health hazard and one of the biggest headaches for hospitals and their constant battle against disease. Researchers from IBM, with the help of scientists in Singapore, revealed today a synthetic antimicrobial hydrogel that can break through diseased biofilms and completely eradicate drug-resistant bacteria upon contact. It is the first hydrogel to be biodegradable, biocompatible, and non-toxic.
Sensors from a spray can: Organic materials increase camera sensitivity
January 23, 2013 5:41 pm | News | CommentsResearchers in Germany have developed a new generation of image sensors that are more sensitive to light than the conventional silicon versions. Simple and cheap to produce, they consist of electrically conductive plastics which are sprayed onto the sensor surface in an ultra-thin layer. The chemical composition of the polymer spray coating can be altered so that even the invisible range of the light spectrum can be captured.
Bisphenol A substitute could spell trouble
January 23, 2013 8:35 am | News | CommentsIn the same week that a team of researchers in France announced the harmful effects of bisphenol A (BPA) on hormone levels in human tissue, researchers in Texas have demonstrated through experiments that the BPA substitute bisphenol S also disrupts hormone activity at an extremely low level of exposure, and in an even more problematic way.
A light switch inside the brain
January 18, 2013 11:06 am | News | CommentsScientists in Germany and Switzerland have developed an implant that is able to genetically modify specific nerve cells, control them with light stimuli, and measure their electrical activity all at the same time. This new tool relies on an innovative genetic technique that forces nerve cells to change their activity by shining light of different colors onto them.
Self-assembled “soft Legos” create complex crystal shapes
January 17, 2013 12:24 pm | News | CommentsA team of researchers in Austria has shown that so-called block copolymer stars—polymers that consist of two different blocks and are chemically anchored on a common point—have a robust and flexible architecture and they possess the ability to self-assemble at different levels. The team has called their invention, which can form complex crystal diamonds or cubes, the “soft Lego”.
New material harvests energy from water vapor
January 10, 2013 2:50 pm | by Anne Trafton, MIT News Office | News | CommentsMassachusetts Institute of Technology engineers have created a new polymer film that can generate electricity by drawing on a ubiquitous source: water vapor. The new material changes its shape after absorbing tiny amounts of evaporated water, allowing it to repeatedly curl up and down. Harnessing this continuous motion could drive robotic limbs or generate enough electricity to power micro- and nanoelectronic devices, such as environmental sensors.
Stopping leaks the way blood does
January 8, 2013 2:00 pm | by David L. Chandler, MIT News Office | News | CommentsA team of Massachusetts Institute of Technology researchers has analyzed the blood clotting process and found, for the first time, exactly how the different molecular components work together to block the flow of blood from a cut. Now, they are working on applying that knowledge to the development of synthetic materials that could be used to control different kinds of liquid flows, and could lead to a variety of new self-assembling materials.
Scientists develop indium-free OLEDs
December 4, 2012 8:56 am | News | CommentsScientists at Ames Laboratory have discovered new ways of using a well-known polymer in organic light-emitting diodes (OLEDs), which could eliminate the need for an increasingly problematic and breakable metal-oxide used in screen displays. The polymer, known as PEDOT:PSS, has been around for about 15 years. However, until recently, the material wasn't sufficiently conductive or transparent enough to be a viable ITO substitute.
ORNL develops lignin-based thermoplastic conversion process
December 3, 2012 7:15 am | News | CommentsTurning lignin, a plant's structural glue and a byproduct of the paper and pulp industry, into something considerably more valuable is driving a research effort headed by Oak Ridge National Laboratory. The research team has developed a process that ultimately transforms the lignin byproduct into a thermoplastic by reconstructing larger lignin molecules either through a chemical reaction with formaldehyde or by washing with methanol.
Scientists image molecular structure of polymer blends
November 29, 2012 9:31 am | News | CommentsUsing an enhanced form of "chemical microscopy" developed at NIST, researchers there have shown that they can peer into the structure of blended polymers, resolving details of the molecular arrangement at sub-micrometer levels. The capability has important implications for the design of industrially important polymers like the polyethylene blends used to repair aging waterlines.
Scientists image the molecular structure of polymer blends
November 28, 2012 11:34 am | News | CommentsUsing an enhanced form of "chemical microscopy" developed at NIST, researchers there have shown that they can peer into the structure of blended polymers, resolving details of the molecular arrangement at sub-micrometer levels. The capability has important implications for the design of industrially important polymers like the polyethylene blends used to repair aging waterlines.
Computer memory could increase fivefold with self-assembly
November 13, 2012 7:39 pm | News | CommentsEngineers in Texas have adopted the nanoscale fabrication technique of directed self-assembly to increase the surface storage density of hard disk drives. The method, which relies on block copolymers, is able to organize magnetic dots into patterns far finer than existing methods. And it does so without risking the integrity of the magnetic fields.
Fighting bacteria with mucus
November 9, 2012 9:28 am | by Anne Trafton, MIT News Office | News | CommentsSlimy layers of bacterial growth, known as biofilms, pose a significant hazard in industrial and medical settings. Once established, biofilms are very difficult to remove, and a great deal of research has gone into figuring out how to prevent and eradicate them. Results from a recent study suggest a possible new source of protection against biofilm formation: polymers found in mucus.
Improving lithium battery performance
November 8, 2012 8:50 am | News | CommentsLithium batteries are used in many devices such as cell phones, computers, and cameras, among others. University of Delaware doctoral student Wei-Fan Kuan is investigating ways to improve membranes used in lithium batteries by capitalizing on the innate properties of block copolymers.
Stem cells and nanofibers produce promising nerve research
November 7, 2012 2:45 pm | News | CommentsNerves often die or shrink as a result of disease or injury. Researchers in Michigan and California have recently reported success in developing polymer nanofiber technologies for understanding how nerves form, why they don’t reconnect after injury, and what can be done to prevent or slow damage. The breakthrough involves growing and myelinating nerve cells along thin polymer nanofibers.
Butterfly wings inspire new high-tech surfaces
November 7, 2012 2:33 pm | by Pam Frost Gorder, Ohio State University | News | CommentsAfter carefully studying the structure of butterfly wings and rice leaves, Ohio State University engineers designed a coated plastic surface resembling a butterfly wing’s texture. Butterflies in the wild need to have bright, clean wings for reproduction and flying, and the surface created by engineers was reportedly easier to keep free of dust particles than a flat surface. The finding could inform designs for a variety of surfaces in various industries.
A step toward stronger polymers
November 6, 2012 8:56 am | by Anne Trafton, MIT News Office | News | CommentsA team from Massachusetts Institute of Technology have developed, for the first time, a way to measure how many loops are present in a given polymer network, an advance they believe is the first step toward creating better materials that don't contain weak spots.
Super-microbes engineered to solve world environmental problems
October 8, 2012 1:29 pm | News | CommentsMicroorganisms isolated from nature use their own metabolism to produce certain chemicals. But they are often inefficient, so metabolic engineering is used to improve microbial performance. Recent work at the Korea Advanced Institute of Science and Technology highlights the potential for engineered organism, such as Escherichia coli, to aid in common industrial processes such as polymer production.
Chemical nanofiber sensor finds landmines and buried IEDs
August 2, 2012 5:21 am | News | CommentsA chemical sensing system developed by engineers at the University of Connecticut is believed to be the first of its kind capable of detecting vapors from buried landmines and other explosive devices with the naked eye rather than advanced scientific instrumentation. The key to the system is a fluorescent nanofiberous film that can detect ultra-trace levels of explosive vapors.
Wrinkled surfaces could have widespread applications
August 1, 2012 4:30 am | by David L. Chandler, MIT News Office | News | CommentsA group of Massachusetts Institute of Technology engineers has discovered a way of making perfectly ordered and repeatable surfaces with patterns of microscale wrinkles. The method involves chemical vapor deposition of a layer onto a stretched silicon-polymer substrate. When tension is released first one way, then the other, a perfectly ordered wrinkled pattern emerges.
