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Graphene Has Excellent Mechanical Properties Graphene is a two-dimensional honeycomb carbon material, composed of carbon atoms in accordance with the 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 is often brought together, not only reduces its adsorption capacity but also affects the excellent performance of graphene itself, thus affecting the performance of graphene reinforced composite materials. 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 graphene agglomeration. One of the commonly used methods is to oxidize graphite and ultrasound to produce off-oxide graphite, and then by chemical method to reduce the graphene, the preparation of graphene between the existence of a strong van der Waals force, easy to gather 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 monolithic graphene 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 can also be used to improve the dispersibility of graphene. In order to improve the surface bonding of graphene and copper matrix, it is possible to obtain the composite material in which the graphene is uniformly dispersed in copper. It is found that the graphene can be uniformly dispersed in the copper matrix by the observation of the composite material. Jing used gallic acid with strong reducing ability as stabilizer and reducing agent to obtain highly dispersible 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.
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Rešetku je odlična mehanička svojstva Rešetku je dvodimenzionalni Saće ugljika materijal, sastavljen od ugljikovih atoma prema 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 često okupio, ne samo da smanjuje kapacitet adsorpcije, ali utječe i na odličan nastup rešetku, dakle utječe na performanse rešetku ojačani kompozitni materijali. 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 za oksidaciju grafit i UZV za proizvodnju s oksid grafita, i zatim kemijskim putem smanjiti rešetku, priprema rešetku između postojanje jake van der Waals sila, polako se 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 disperzije monolitni rešetku. 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. Kako bi se poboljšala površinska vezivanja rešetku i bakrene matrice, to je moguće dobiti kompozitnog materijala u kojem rešetku ravnomjerno raspršene u bakar. Utvrđeno je da rešetku mogu ravnomjerno raspršiti u bakrene matrice promatranje kompozitnog materijala. Jing koristi gallic kiselina s jakim smanjenje sposobnosti kao stabilizator i smanjenje agent za dobivanje visoko oralnu 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.