3016-76-0Relevant articles and documents
Highly hydrophobic metal-organic framework for self-protecting gate dielectrics
Chen, Jenq-Wei,Chiang, Ming-Hsi,Chiou, Kuan-Ru,Inamdar, Arif I.,Kamal, Saqib,Liu, Yen-Hsiang,Lu, Kuang-Lieh,Mendiratta, Shruti,Pathak, Abhishek,Tsai, Pei-Hsien,Usman, Muhammad
, p. 11958 - 11965 (2020)
A hydrophobic metal-organic framework (MOF) showing high-κ behaviour was synthesized by the reaction of copper ions with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (HFDPA). The unique, highly hydrophobic nature of the material protects it from re-adsorbing water, even in a high humidity environment. The dielectric constant of the MOF showed an unprecedented increasing trend, reaching up to κ ≈ 99 at 300 K and 1 kHz after the complete removal of guest and coordinated water molecules. The unusual dielectric behaviour of the compound along with its water resistant properties is the first report of such behaviour and it paves the way for the development of moisture-stable microelectronic devices.
Preparation method of hexafluorodianhydride
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, (2021/10/11)
The invention relates to the field of preparation of fluorine-containing monomers, and particularly discloses a preparation method of hexafluorodianhydride. The preparation method comprises the following steps: S1, preparation of hexafluorotetracid according to the following reaction process flow: step (1), with o-dichlorobenzyl and hexafluoroacetone used as raw materials, adding a catalyst, and performing stirring reflux at 130-150 DEG C for 20-40 h to obtain a product a; step (2), hydrolyzing the product a into a product b under an alkaline condition; step (3), oxidizing a hydroxyl group into an aldehyde group to obtain a product c; and step (4), oxidizing the aldehyde group into a carboxyl group to obtain hexafluorotetracid; and S2, preparation of hexafluorodianhydride according to the reaction process flow that hexafluorotetracid is dehydrated and anhydridized to prepare hexafluorodianhydride. Compared with the prior art, the preparation method provided by the invention has the advantages that reaction conditions in the whole process are mild, the use of a potassium permanganate strong oxidant is avoided in a route, requirements on a reaction container are lower, and reaction safety is higher.
Synthesis method of 4, 4-(hexafluoroisopropenyl) diphthalic anhydride
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, (2020/09/09)
The invention belongs to the technical field of synthesis of 4, 4-(hexafluoroisopropenyl) diphthalic anhydride, in particular to a synthesis method of 4, 4-(hexafluoroisopropenyl) diphthalic anhydride. The synthesis method has the advantages of easy separation of intermediate products, high yield, less waste and good economic benefit, and a mixed solvent of isobutanol and butyl acetate is adoptedto reduce the solubility of the product, facilitate the separation of the product and increase the yield. Besides, the Pd/C catalyst is pretreated, a proper amount of sulfide is added for pretreatment, the sulfur poisoning resistance of the catalyst is improved, the service life of the catalyst is prolonged, and the application frequency of the catalyst is increased; because nitro compounds contain trace amount of sulfides such as sulfuric acid and like, catalyst is easily poisoned. In the step 2, an alumina-silica gel catalyst is added so that 2, 2-bis (3-amino-4-hydroxyphenyl) molecules canbe adsorbed on the surface of the catalyst in a flat shape, hydroxyl is closer to the surface of the catalyst, and the amination reaction of hydroxyl is facilitated; in the step 4, a small amount of urea is added in the cyanolysis reaction to prevent diazonium salt from being oxidized, becoming tar and other side reactions.
