Rice University scientists build electronic application of the "super" graphene epoxy resin and epoxy resin foam better chemist James Tour of Rice Laboratories compared purity higher than pure epoxy, other than Epoxy resin composites are more conductive while maintaining a low density of materials. It is possible to improve currently used epoxy resin, by adding a conductive filler to weaken the structure of the material. The new material is described in detail in the American Chemical Society journal ACS Nano in. Epoxy resin itself is an insulator commonly used in coatings, adhesives, electronics, industrial tools and structural composites. Metal or carbon fillers are often added for applications that require electrical conductivity, such as electromagnetic shielding.

But there is a trade-off: more fillers bring better conductivity at the expense of weight and compressive strength, and composites become more difficult to process. The Rice solution replaces metal or carbon powder with a three-dimensional foam made of nano-scale graphene sheets, which are atomic-thick carbon. Tourism in cooperation with the Laboratory of Rice materials scientist Pulickel Ajayan, Rouzbeh Shahsavari, Jun Lou Beijing Beijing University of Aeronautics and Yan Zhao, project three-dimensional scaffold from epoxy resin injected into the inspiration, including graphene airgel, foam and all kinds of The skeleton of the craft.

The new solution consists of a stronger scaffold made of polyacrylonitrile (PAN), a powdered polymer resin used as a carbon source mixed with nickel powder. In a four-step process, they cold-pressed the material to make it dense, heated in a furnace to turn the PAN into graphene, chemically treated the resulting material to remove nickel and vacuum to pull the epoxy to the current porous material. “The graphene foam is a single layer of graphene,” says Tour. “Therefore, in fact, the entire foam is a macromolecule. When the epoxy penetrates the foam and hardens, any bending of the epoxy in one place can put pressure on the overall material in many other locations due to the embedded graphene support. The entire structure."

According to the researchers, ice-spheric composites with 32% foam are slightly dense, but the conductivity per centimeter is about 14 Siemens (measurement of conductivity or anti-ohms). The foam did not add significant weight to the compound, but its purity was 7 times the compressive strength of the epoxy resin. A simple interlock between graphene and epoxy also helps stabilize the structure of the graphene. “When the epoxy penetrates the graphene foam and then hardens, the epoxy is trapped in the micron-sized area of ​​the graphene foam,” says Tour.

The lab raises the stake by mixing multi-walled carbon nanotubes into graphene foam. The nanotube acts as a reinforcing strip bonded to graphene, making the composite 1732% harder than pure epoxy resin and nearly three times more conductive, about 41 Siemens/cm, much higher than almost all stent-based rings reported so far. Oxygen resin composites, according to researchers. Tour expects the process to scale for the industry. “People only need a large enough stove to produce the final part,” he said. “But this has been done by cold pressing and then heating to make large metal parts.” He said the material could initially replace the carbon composite resin used to pre-impregnate and enhance fabrics used in aerospace structures to tennis racket materials.

Xb200 Asbestos Rubber Gasket

Description:XB200 Asbestos Rubber Gasket is a kind of low pressure asbestos sealing materials,it made by good asbestos fiber with rubber and other chemical materials ,compression molding it in thick paper fashion.

Usage:Suitable for ordinary water caliduct equipment and low pressure.For water and steam transmitted in the joints of facilities and pipelines.

TEMP:200℃(max)

PRESS:1.5MPa(max)

Dimension:
4100×1500mm; 4500 x 1500mm;2000×1500mm;

1500×1500mm;1500×1000mm;1540x1360mm

1270×1300mm; 3810×1300mm 

Thickness:  0.5~6.0mm

Technical data:

Lateral Tensile Strength/MPa        â‰¥ 6.0

Aging coefficient                           ≥  0.9

Loss on ignition/%                         ≤  30.0

Compression ratio/%                     7~17

Recovery/%                                   ≥  35

Creep relaxation rate/%                ≤   50

Density(g/cm3)                           1.6~2.0

XB200 Asbestos Rubber Gasket

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