Claisen thermally rearranged (CTR) polymers
نویسندگان
چکیده
Thermally rearranged (TR) polymers, which are considered the next-generation of membrane materials because of their excellent transport properties and high thermal and chemical stability, are proven to have significant drawbacks because of the high temperature required for the rearrangement and low degree of conversion during this process. We demonstrate that using a [3,3]-sigmatropic rearrangement, the temperature required for the rearrangement of a solid glassy polymer was reduced by 200°C. Conversions of functionalized polyimide to polybenzoxazole of more than 97% were achieved. These highly mechanically stable polymers were almost five times more permeable and had more than two times higher degrees of conversion than the reference polymer treated under the same conditions. Properties of these second-generation TR polymers provide the possibility of preparing efficient polymer membranes in a form of, for example, thin-film composite membranes for various gas and liquid membrane separation applications.
منابع مشابه
Tuning microcavities in thermally rearranged polymer membranes for CO2 capture.
Microporous materials have a great importance in catalysis, delivery, storage and separation in terms of their performance and efficiency. Most microporous materials are comprised of inorganic frameworks, while thermally rearranged (TR) polymers are a microporous organic polymer which is tuned to optimize the cavity sizes and distribution for difficult separation applications. The sub-nano size...
متن کاملGold(I)-catalyzed formation of furans by a Claisen-type rearrangement of ynenyl allyl ethers
A series of ynenyl allyl ethers were rearranged into polysubstituted furans in the presence of a gold(I) catalyst. It is proposed that the transformation involves a Claisen-type rearrangement that allows the efficient creation of quaternary centers under mild experimental conditions.
متن کاملPreparation and Properties of Thermally Stable Polyureas Containing Ether and Ketone Units
The main objective of this search was to prepare novel soluble polyureas with improved thermal stability. Accordingly, a new types of polyureas was prepared through the polycondensation reaction of a prepared diamine containing ether, keto, and naphthyl groups with 4,4’-diphenylmethan diisocyanate (MDI), toluene-2,4-diisocyanate (TDI), and isophorone diisocyanate (IPDI) in N-methyl-2-pyrrol...
متن کاملCentral composite experimental design applied to fabrication of LLDPE microporous membrane via thermally induced phase separation (TIPS) method
متن کامل
Correction: Highly lithium-ion conductive battery separators from thermally rearranged polybenzoxazole.
Correction for 'Highly lithium-ion conductive battery separators from thermally rearranged polybenzoxazole' by Moon Joo Lee et al., Chem. Commun., 2015, 51, 2068-2071.
متن کامل