""Our goal was to develop an eco-friendly herding molecule as an alternative to the current silicone-based polymers,
and duration by creating a gel with 3d microscopic structures of a polymer compound called polyethylene glycol (PEG) that resembles"reservoirs."
Compared to other polymers like plastics, the wood nanomaterial is biocompatible and has relatively low thermal expansion coefficient,
They have been able to make further chemical modifications to the pores of the 3dom hydrogels by grafting with organic compounds and polymers.
A number of polymer structures were tested for their ability to deliver DNA into two rat glioma cell lines.
Among the many polymers tried, the one known as PBAE 447 was found to be the most efficient in delivering the HSVTK gene into the cultured rat glioma cells.
#Polymer mold makes perfect silicon nanostructures Using molds to shape things is as old as humanity.
In a breakthrough for nanoscience, Cornell polymer engineers have made such a mold for nanostructures that can shape liquid silicon out of an organic polymer material.
whose lab previously has led the creation of novel materials made of organic polymers. With the right chemistry, organic polymers self-assemble,
and the researchers used this special ability of polymers to make a mold dotted with precisely shaped and sized nanopores.
Normally, melting amorphous silicon, which has a melting temperature of about 2, 350 degrees, would destroy the delicate polymer mold,
which degrades at about 600 degrees. But the scientists in collaboration with Michael Thompson, associate professor of materials science and engineering, got around this issue by using extremely short melt periods induced by a laser.
The researchers found the polymer mold holds up if the silicon is heated by laser pulses just nanoseconds long.
but the melt duration is so short the polymer doesn't have time to oxidize
They essentially tricked the polymer mold into retaining its shape at temperatures above its decomposition point.
Semiconductors like silicon don't self-assemble into perfectly ordered structures like polymers Do it's almost unheard of to get a 3-D structured single crystal of a semiconductor.
porous nanomaterials using specially structured molecules called block copolymers. They first used a carbon dioxide laser in Thompson's lab to"write"the nanoporous materials onto a silicon wafer.
contained a block copolymer, which directed the assembly of a polymer resin. Writing lines in the film with the laser,
the block copolymer decomposed, acting like a positive-tone resist, while the negative-tone resin was left behind to form the porous nanostructure.
That became the mold.""We demonstrated that we can use organic templates with structures as complicated as a gyroid, a periodically ordered cubic network structure,
which makes polymer products more pliable and is still in use. igher everyday exposure levels were associated with menopause coming,
The Harvard team solved these problems by using a mesh of conductive polymer threads with either nanoscale electrodes
Neurons ook at this polymer network as friendly, like a scaffold he says. The next steps will be to implant larger meshes containing hundreds of devices, with different kinds of sensors,
they developed a 3-D printing process that uses two types of polymers: one rigid, one flexible.
The printer inserts an array of the rigid polymers into a bed of squishy material composed of the more flexible type.
its naturally smooth surface takes on a patterned texture that depends on the spacing and shapes of the embedded rigid polymers.
its rigid polymers are stuck in a fixed array and cannot change positions relative to one another.
For example, by using elongated rigid polymers instead of spherical ones, scientists could create surfaces that are smooth along one direction but ridged in the opposite direction.
Some rigid polymers might yield differently textured surfaces depending on the strength of the applied force.
but further compression would cause the polymers to rotate relative to one another, creating a different topography.
Other polymers could swell or shrink relative to the soft material. In the sample Guttag and Boyce printed to physically test their code,
the rigid polymers were about a centimeter in diameter and the bed of soft material was about a meter across.
The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick
since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
the UW-Madison team drew on cutting-edge technologies that use polymers to selectively sort out the semiconducting nanotubes,
#New catalyst process uses light not metal for rapid polymerization A team of chemistry and materials science experts from University of California,
Santa barbara and The Dow chemical Company has created a novel way to overcome one of the major hurdles preventing the widespread use of controlled radical polymerization.
In a global polymer industry valued in the hundreds of billions of dollars, a technique called Atom Transfer Radical Polymerization is emerging as a key process for creating well-defined polymers for a vast range of materials, from adhesives to electronics.
However, current ATRP methods by design use metal catalysts a major roadblock to applications for which metal contamination is an issue,
This new method of radical polymerization doesn involve heavy metal catalysts like copper. Their innovative, metal-free ATRP process uses an organic-based photocatalyst
Their study was recently detailed in a paper titled etal-Free Atom Transfer Radical Polymerization, published in the Journal of the American Chemical Society.
but the new metal-free rapid polymerization process ushes controlled radical polymerization into new areas and new applications, according to Hawker. any processes in use today all start with ATRP.
Controlling radical polymerization processes is critical for the synthesis of functional block polymers. As a catalyst, phenothiazine builds block copolymers in a sequential manner,
achieving high chain-end fidelity. This translates into a high degree of versatility in polymer structure,
as well as an efficient process. ur process doesn need heat. You can do this at room temperature with simple LED LIGHTS,
said Hawker. ee had success with a range of vinyl monomers, so this polymerization strategy is useful on many levels. he development of living radical processes,
such as ATRP, is arguably one of the biggest things to happen in polymer chemistry in the past few decades,
he added. his new discovery will significantly further the whole field. w
#Chemists one step closer to new generation of electric car battery Lithium sulphur (Li-S) batteries can theoretically power an electric car three times further than current lithium-ion batteries for the same weight at much
Solid Polymer Ionic Liquid (SPIL) electrolyte enables the ultra-thin lithium metal anode and improves the cell-level energy density by 50%compared to graphite anodes
they will be manufactured from polymer-lined 5 mm-thick carbon fibre in the finished model. The lightweight lithium-polymer hybrid fuel cell that converts the hydrogen gas into electricity to power the rotors was developed by a sister company,
called Horizon Energy systems. y removing the design silos that typically separate the energy storage component from UAV frame development,
Gong and her students also have been based studying bio polymers for more than a decade. CNF offers many benefits over current chip substrates, she says. he advantage of CNF over other polymers is that it a bio-based material and most other polymers are based petroleum polymers.
Bio-based materials are sustainable biocompatible and biodegradable, Gong says. nd, compared to other polymers,
CNF actually has a relatively low thermal expansion coefficient. The group work also demonstrates a more environmentally friendly process that showed performance similar to existing chips.
we noticed that it was almost invisible and very flexible like a polymer and could literally be sucked into a glass needle or pipette.
researchers lay out a mesh of nanowires sandwiched in layers of organic polymer. The first layer is dissolved then, leaving the flexible mesh,
The global market for polymers such as this approaches $7 billion, and there are estimates the U s. spends up to $120 billion a year on probiotic products such as yogurt, sour cream and buttermilk.
beginning in the early 1990s when a novel polymer with an ability to rapidly thicken milk was discovered by an OSU microbiologist.
The polymer is known as Ropy 352 and produced by a non-disease-causing bacterium. his is one of many naturally occurring,
never-before reported grouping of genes that code for a unique polymer that naturally thickens milk.
In basic research, wee also broadened our understanding of how and why non-disease-causing bacteria produce polymers.
This polymer appears to give fermented foods a smooth thick, creamy property, and may initially find uses in sour cream, yogurt, kefir, buttermilk, cream cheese and artisan soft cheeses.
And unlike other polymers that are used now commonly as thickeners, it may add probiotic characteristics to foods,
non-disease-causing bacterial strains that produce unique polymers with characteristics desirable and safe for food products,
One of the most common polymers, xanthum gum, has been in use since 1969 and is found in a huge range of food products, from canned foods to ice cream, pharmaceuticals and beauty products.
Trempy research program has determined the new polymer will thicken whole and nonfat milk, lactose-free milk, coconut milk, rice milk,
Beyond that, the polymer may have a wide range of applications such as thickening of pharmaceuticals, nutraceuticals, fruit juices, cosmetics and personal care products.
In their broader uses, microbial polymers are used for food production, chemical production, detergents, cosmetics, paints, pesticides, fertilizers, film formers, lubricants, explosives, pharmaceutical production and waste treatment.
Polymer material produced by a 3-D printer includes soft, flexible material (clear or lighter tone) with particles of hard material (black) embedded, in predetermined arrangements.
involves a material that is composed of two different polymers with different degrees of stiffness: More rigid particles are embedded within a matrix of a more flexible polymer.
When squeezed, the material surface changes from smooth to a pattern determined by the spacing and shapes of the implanted harder particles;
In the acetone-soluble prototype, the outer layers were polystyrene. Slits cut into the outer layers by a laser cutter guide the folding process.
The scientists devised a new arrangement of solar cell ingredients, with bundles of polymer donors (green rods) and neatly organized fullerene acceptors (purple, tan.
you can vastly improve the retention of energy. he two components that make the UCLA-developed system work are a polymer donor and a nanoscale fullerene acceptor.
The polymer donor absorbs sunlight and passes electrons to the fullerene acceptor; the process generates electrical energy.
The plastic materials, called organic photovoltaics, are organized typically like a plate of cooked pasta a disorganized mass of long, skinny polymer paghettiwith random fullerene eatballs.
because the electrons sometimes hop back to the polymer spaghetti and are lost. The UCLA technology arranges the elements more neatly like small bundles of uncooked spaghetti with precisely placed meatballs.
The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerene
which can effectively keep the electrons away from the polymer for weeks. hen the charges never come back together,
these particles are coated with polymers, which fine-tune their optical properties and their rate of degradation in the body.
These polymers can be loaded with drugs that are released gradually. Finally, carbon nanoparticles are rather small, less than eight nanometres in diameter (in comparison,
Scientists also found that they can alter the infusion of the particles into melanoma cells by adjusting the polymer coatings.
Scientists say that they can be coated with different polymers to give them different optical properties to make them even easier to detect in the organism,
a conductive polymer material that responds to electromagnetic fields. Wen Gao, a postdoctoral researcher in the Center for Paralysis Research who worked on the project with Borgens,
and the shape change of the polymer that allows it to store and release drugs,
the polymer snaps back to the initial architecture and retains the remaining drug molecules . or each different drug the team would need to find the corresponding optimal electromagnetic field for its release,
and Steven P. Levitan, Phd, John A. Jurenko Professor of Electrical and Computer engineering, integrated models for self-oscillating polymer gels and piezoelectric micro-electric-mechanical systems to devise a new
When pressure is increased in the pores of the polymer, the structure swells and expands in a preferred direction.
The walls of the cells are made of a non-swellable polymer; a swellable polymer fills the interior of the chambers.
If the pressure inside the cells increases, for example, because the swellable polymer absorbs liquids, the structure expands in one direction.
Advanced Materials Interfaces/MPI of Colloids and Interfacesif you enjoy walking in the woods, you may well be familiar with the phenomenon.
To this end, they developed a computer simulation as well as tissue-like materials from a porous polymer in
Moveable parts of such robots, the actuators, might consist of a porous polymer with precisely defined pore properties. he actual motion could then be controlled by compressed air or an expandable fluid in the pores
The researchers were delighted also that the theoretical predictions from the computer simulation almost perfectly matched the results of their tests on synthesized porous polymer materials.
says Dunlop. Synthetic polymer honeycomb structures from a 3d printerthe composition of the cell walls plays a key role in the expansion process in the relevant cells of pinecones
The researchers simulated this structure for their practical experiments by bonding two different swellable polymer layers together.
The scientists envisage using porous polymer materials whose pores are filled with a hygroscopic fluid, for example a superabsorbing hydrogel, in future practical applications.
#Polymer mold makes perfect silicon nanostructures Using molds to shape things is as old as humanity.
In a breakthrough for nanoscience, Cornell polymer engineers have made such a mold for nanostructures that can shape liquid silicon out of an organic polymer material.
whose lab previously has led the creation of novel materials made of organic polymers. With the right chemistry, organic polymers self-assemble,
and the researchers used this special ability of polymers to make a mold dotted with precisely shaped and sized nanopores..
Normally, melting amorphous silicon, which has a melting temperature of about 2, 350 degrees, would destroy the delicate polymer mold,
which degrades at about 600 degrees. But the scientists, in collaboration with Michael Thompson, associate professor of materials science and engineering, got around this issue by using extremely short melt periods induced by a laser.
The researchers found the polymer mold holds up if the silicon is heated by laser pulses just nanoseconds long.
but the melt duration is so short the polymer doesn have time to oxidize and decompose.
They essentially tricked the polymer mold into retaining its shape at temperatures above its decomposition point.
Semiconductors like silicon don self-assemble into perfectly ordered structures like polymers Do it almost unheard of to get a 3-D structured single crystal of a semiconductor.
porous nanomaterials using specially structured molecules called block copolymers. They first used a carbon dioxide laser in Thompson lab to ritethe nanoporous materials onto a silicon wafer.
contained a block copolymer, which directed the assembly of a polymer resin. Writing lines in the film with the laser,
the block copolymer decomposed, acting like a positive-tone resist, while the negative-tone resin was left behind to form the porous nanostructure.
That became the mold. e demonstrated that we can use organic templates with structures as complicated as a gyroid, a periodically ordered cubic network structure,
as well as semiconductive and conductive polymers to tailor the behavior of natural cotton fibers. he layers were so thin that the flexibility of the cotton fibers is preserved always,
which are coated with a charged polymer layer that helps them adhere to the target microbes,
These materials include activated carbons, zeolites, metal-organic framework materials and certain porous polymers which act as olecular sponges Solid-like behaviour Using inelastic neutron scattering,
demonstrated that the conducting elastomers can be fabricated in diameters ranging from the very small about 150 microns,
string-like polymers storing the genetic information of life and, in a cell, are packed tightly into structures called chromosomes.
However, these devices, often created with nondegradable elastic polymers, bear an inherent risk of intestinal obstruction as a result of accidental fracture or migration.
Now, researchers at MIT Koch Institute for Integrative Cancer Research and Massachusetts General Hospital (MGH) have created a polymer gel that overcomes this safety concern
This polymer is ph-responsive: It is stable in the acidic stomach environment but dissolves in the small intestine near-neutral ph,
and folding of devices into easily ingestible capsules meaning this polymer can be used to create safe devices designed for extremely prolonged residence in the stomach. ne of the issues with any device in the GI TRACT is that there the potential for an obstruction,
polymer gel for creating gastric devices. Shiyi Zhang, a postdoc at the Koch Institute, is the paper lead author.
the researchers were interested in developing a polymer with elastic properties. n elastic device can be folded into something small,
But the size and shape of existing devices with elastic polymers have been limited by safety concerns,
Because of this, the researchers wanted their polymer to also be enteric or have a mechanism that would enable it to pass through the stomach unaltered before disintegrating in the intestines. o lower any possible risk of obstruction,
the researchers synthesized an elastic polymer and combined it in solution with a clinically utilized enteric polymer.
Adding hydrochloric acid and centrifuging the solution resulted in a flexible, yet resilient, polymer gel that exhibits both elastic and enteric properties.
The researchers used the gel polycaprolactone (PCL), a nontoxic, degradable polyester, to construct several device prototypes.
They first created ring-shaped devices by using the gel to link arcs of PCL in a circular mold.
the polymer gel dissolved, allowing for the safe passage of the small PCL pieces without obstruction.
Improving adherence The combined enteric and elastic properties of this polymer gel could significantly improve the design and adoption of gastric-resident devices.
With further work in adjusting the polymer composition or the design of the system they say that they could tailor devices to release drugs over a specific timeframe of up to weeks or months at a time.
Ribo-T may be able to be tuned to produce unique and functional polymers for exploring ribosome functions
or producing designer therapeutics and perhaps one day even non-biological polymers. No one has developed ever something of this nature. e felt like there was a small very small chance Ribo-T could work
the mesh is composed of nanoscale metal wires and polymers. Tiny electronic devices, such as sensors and electrode stimulators, can be built into it.
The researchers have been studying bio-based polymers for more than a decade. While they showed some promise,
The skin the team has developed is made from a soft electroactive dielectric elastomer, coated with black carbon grease.
Applying a current makes this elastomer expand and contract. Arranging these artificial chromatophores in a linear array, the team devised mathematical algorithms to control how the cells react to changes in state of neighbouring cells,
rubbery polymer with carbon grease electrodes, expand and contract in response to elextric current In a paper in the Journal of the Royal Society Interface,
#Superabsorbent Polymer Blows Up Brain Samples To Give a Better View Researchers have come up with an inexpensive technique for enlarging brain samples
They want to find more substances that can expand the specimens even more. ne thing we want to do is figure out how to expand the polymers even more.
Another priority for us is to build stronger polymers, or find a way of reinforcing them in the expanded state,
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