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Graphene Special Structure Graphene is a two-dimensional honeycomb carbon material, composed of carbon atoms in hexagonal arrangement. Carbon and carbon atoms by the combination of sp2 hybrid, its structure is very stable. The special structure of graphene leads to its many excellent properties. Graphene is currently found in the hardness of the largest material, and has excellent mechanical properties, the theoretical surface area of up to 2600m2 / g, with outstanding thermal conductivity, up to 3000W / (m · K). In addition, graphene also has good conductivity. At room temperature, its electron mobility can be as high as 20000cm2 / (V · s). Due to the excellent properties of graphene, the researchers consider adding it as a reinforcement to the matrix material to improve the performance of the matrix material. However, the specific surface area of graphene tends to be agglomerated together, which not only reduces its adsorption capacity but also affects the excellent performance of graphene itself, thus affecting the performance of graphene reinforced composites. Moreover, this reunion is irreversible, unless the application of external forces, such as ultrasound and strong mixing, so that evenly dispersed. In order to obtain excellent graphene reinforced composites, researchers have done some research in overcoming the graphene agglomeration. One of the commonly used methods is the preparation of off-oxide graphite by oxidized graphite and ultrasound, and then chemically reduced to graphene. There is a strong van der Waals force between the graphene prepared in this method and easy to accumulate in the solution. Another common method is to uniformly disperse the graphene in an organic solvent or an aqueous solution of a surfactant to adsorb the molecular or surfactant molecules on the surface of the graphene, and to achieve the effect of the monoclinic graphene by the classical repulsive force and the intermolecular force dispersion. The ability to inhibit the agglomeration of graphene by physical or chemical modification has been demonstrated, but whether the impurity introduced during the formation of the composite affects the properties of the composite remains to be studied. Some surface modifications and other methods may also be used to improve the dispersibility of graphene. Jiang by surface modification of graphene, thereby improving the interface between graphene and copper matrix, polystyrene in the copper uniform dispersion of the composite material. The morphology of the composites was found to be uniformly dispersed in the copper matrix. Jing used gallic acid with strong reducing ability as stabilizer and reducing agent to obtain high dispersibility of graphene. Their analysis is due to the formation of π-π conjugate interactions between the benzene ring structure and the graphene in the molecule, which is adsorbed on the surface of the graphene as a stabilizer. This makes the graphene sheet has a strong negative charge, to prevent the further accumulation of graphene together to make it more difficult to reunite, to ensure that the prepared graphene has a high dispersion performance. Through the above test can be seen, the material or process can be used to make gravel evenly dispersed in the matrix, thereby enhancing the performance of composite materials.
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Rešetku je dvodimenzionalni Saće ugljika materijal, sastavljen od ugljikovih atoma u šesterokutni aranžman. Ugljena i ugljikovih atoma kombinacijom sp2 hibrida, njegova struktura je vrlo stabilan. Specijalna struktura rešetku dovodi do mnogih izvrsna svojstva. Rešetku se trenutno nalazi u tvrdoće najveći materijal i ima odlična mehanička svojstva, teorijska površine do 2600m 2 / g, s izvanredna Toplinska vodljivost, do 3000W / (m · (K). osim toga, rešetku također ima dobru vodljivost. Na sobnoj temperaturi, njegova pokretljivost elektrona može doseći i 20000cm 2 / (V · s). Zbog izvrsna svojstva rešetku, istraživači, možete dodati kao pojačanje u matricu materijal za poboljšanje svojstava materijala matrice. Međutim, specifične površine rešetku sklon aglomerirani zajedno, koji ne samo da smanjuje kapacitet adsorpcije ali utječe i na odličan nastup rešetku, čime utječe na performanse rešetku ojačani kompoziti. Osim toga, ovo okupljanje je nepovratan, osim ako aplikacija vanjske snage, kao što su ultrazvuk i jako miješanje, tako da se ravnomjerno raspoređuje. Kako bi dobili odličan rešetku ojačani kompoziti, istraživači učinili neke istraživanja u prevladavanju rešetku aglomeracija. Jedan od najčešće korištenih metoda je priprema se oksid grafita oksidirani grafit i ultrazvuk, a zatim kemijski smanjio za rešetku. Postoji jaka van der Waalsove sile između rešetku pripremljen na ovaj način i lako da se akumuliraju u rješenje. Druga uobičajena metoda je ravnomjerno raspršiti rešetku u organskim otapalom ili vodene otopine površinski da ni da apsorbira na molekularnu ili površinski molekule na površini rešetku i postići efekt monoklinski rešetku od u klasične odbojna sila i međumolekulske sile disperzije. Dokazana je sposobnost da inhibiraju briketiranje rešetku od fizičkih ili kemijskih modifikacija, ali da li nečistoće predstavljen tijekom formiranja kompozitni utječe na svojstva kompozit ostaje da se. Neke površinske modifikacije i druge metode mogu se koristiti za poboljšanje dispersibility rešetku. Jiang po površinska modifikacija rešetku, čime se poboljšava sučelje između rešetku i bakrene matrice, polistirena u bakar uniformi disperzija kompozitnog materijala. Morfologija fotorobot utvrđeno je da ravnomjerno raspršiti u bakrene matrice. Jing koristi gallic kiselina s jakim smanjenje sposobnosti kao stabilizator i smanjenje agent za postizanje visoke dispersibility rešetku. Njihova analiza je zbog formiranja π π konjugirati interakcije između strukturu benzena i rešetku u molekula adsorbiranih na površini rešetku kao stabilizator. To čini rešetku list ima jak negativan naboj, spriječiti daljnje nakupljanje rešetku zajedno da bi ga više teško ujediniti, da bi se osiguralo da je spreman rešetku ima visoke disperzije performanse. Kroz gore navedeni test se može vidjeti, materijal ili proces može biti naviknut izraditi šljunka ravnomjerno raspršenih u matrici, time povećava performanse kompozitne materijale.