Disilyl Bis(Secondary Amine)-Enabled Epoxy Ring-Opening and Silylotropic N → O Migration Leading to Low Dielectric Epoxy Copolymers

2021 ◽  
Author(s):  
Jiang Duan ◽  
Caihong Mei ◽  
Wenli Wu ◽  
Li Rao ◽  
Heping Fan ◽  
...  
2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jing Zhang ◽  
Ji Jun Tang ◽  
Jiao Xia Zhang

Several biorenewable vegetable oil-based polyols with different molecular weights and various hydroxyl functionalities were successfully prepared by ring-opening epoxidized soybean oil with a castor oil-based fatty diol. It was found that several factors, including reaction time, reaction temperature, and molar ratios between epoxidized soybean oil and castor oil diol, affect structures and rheology behaviors of the final polyols. Proton NMR, FT-IR, GPC, and rheometry results revealed that the hydroxyl functionalities, molecular weight, and viscosity of the polyols could be tailored by controlling the above-mentioned factors. Besides, the role of solvents in the epoxy ring-opening process was investigated as well.


2019 ◽  
Vol 36 (3) ◽  
pp. 1165-1173 ◽  
Author(s):  
Kaline A. Wanderley ◽  
Amanda M. Leite ◽  
Gabriel Cardoso ◽  
Anderson M. Medeiros ◽  
Caroline L. Matos ◽  
...  

Nanomaterials ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 350 ◽  
Author(s):  
Alina Pruna ◽  
Alfonso Cárcel ◽  
Adolfo Benedito ◽  
Enrique Giménez

Low-density three-dimensional (3D) N-doped graphene aerogels by a one-step solvothermal method in the presence of ethylenediamine (EDA) are reported. The gelation, formation, and properties of the aerogels were studied with solvothermal conditions, namely, operating temperature, time, graphene oxide (GO) concentration, and the GO/EDA w/w ratio. Two ranges of solvothermal conditions are employed: one involving an operating temperature below 100 °C and a conventional chemical reduction of GO with EDA at atmospheric pressure and a second one employing a higher temperature range up to 165 and a high pressure reduction with EDA. The results show that both solvothermal approaches allow for the fabrication of homogeneous N-doped 3D graphene aerogels with density values close to 10 mg cm−3. The measurements indicated that low values of GO concentration, temperature, and EDA are optimum for obtaining low-density 3D aerogels. N doping is improved with an EDA amount in lower temperature conditions. The N doping mechanism below 100 °C is dominated by the epoxy ring opening while at temperatures up to 165 °C both epoxy ring opening and amidation take place. The CO2 adsorption properties are strongly controlled by the nitrogen configuration, namely, pyridinic nitrogen in terms of its density.


2018 ◽  
Vol 41 (4) ◽  
pp. 856-867 ◽  
Author(s):  
Gaowa Jin ◽  
Yanming Liu ◽  
Fan Yang ◽  
Dongping Yu ◽  
Jingyu Yan ◽  
...  

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2513 ◽  
Author(s):  
Bo-Xin Lai ◽  
Saurav Bhattacharjee ◽  
Yi-Hao Huang ◽  
An-Bang Duh ◽  
Ping-Chieh Wang ◽  
...  

A functional greener solvent mixture containing water, isopropyl alcohol (IPA) and ethyl acetate with the ratio 10:20:70 (wt%) was found to accelerate hydrogenation of bisphenol A type epoxy resin BE503 with a molecular weight of 1500 through an on-water mechanism, and led to an increased H2 availability, due to high solubility of H2 in IPA. Different carbon-based supports were tested and VulcanXC72 was found as the best support among the tested carbon-based ones as it possessed the highest amount of electron deficient promoter, RhOx. The catalyst, Rh5/VulcanXC72-polyol, synthesized by the microwave assisted polyol method, yielded a 100% hydrogenation of aromatic rings with an epoxy ring opening below 20.0% at 50 °C and a H2 pressure of 1000 psi in 2.25 h. Intrinsic activation energies for the hydrogenation of aromatic rings and epoxy ring opening were experimentally estimated and a mechanism for the hydrogenation of BE503 was proposed, wherein the hydrogenation of aromatic rings and epoxy ring opening in BE503 proceeded simultaneously in parallel and in-series with parallel being the major pathway.


ChemInform ◽  
2005 ◽  
Vol 36 (52) ◽  
Author(s):  
Swapan Pramanick ◽  
Suparna Mandal ◽  
Sibabrata Mukhopadhyay ◽  
Sailen Jha

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