75835-96-0Relevant academic research and scientific papers
Writing monomer, preparation method thereof, photopolymer composition and grating thereof
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Paragraph 0225-0228, (2021/10/27)
The invention relates to a writing monomer, a preparation method thereof, a photopolymer composition and a grating thereof. The writing monomer is a fluorenyl-containing carbamate acrylate monomer, and has the following general formula structure: Fl-[Ar-NH-C (O)-O-R0-O-C(O)-C(R1)=C(R2)2]m, wherein Fl represents fluorenyl which can be substituted by phenyl, C1-C6 alkyl or alkoxy, or halogen, and phenyl, alkyl or alkoxy can be optionally substituted by halogen; the Ar represents a phenyl group, a biphenyl group or a naphthyl group which may be substituted by a phenyl group, a C1-C6 alkyl group, an alkoxy group or a halogen, and the phenyl group, the alkyl group or the alkoxy group may be optionally substituted by the halogen; if there are a plurality of Ar groups, the Ar groups can be bonded with each other; R0 represents a straight-chain or branched-chain alkyl group having 1-10 carbon atoms, and R0 may be substituted or not substituted; m represents an integer of 1 or 2; R1 is H or CH3; and R2 is the same or different in each occurrence and independently represents a hydrogen atom or a halogen atom.
Synthesis, characterization, and evaluation of novel polyhydantoins as gas separation membranes
Tejero, Ruben,Lozano, Angel E.,Alvarez, Cristina,De Abajo, Javier
, p. 4052 - 4060 (2013/09/23)
Novel polyhydantoins (PHYs) were synthesized from original aromatic diisocyanates and bisiminoacetates by a two-step polycondensation procedure, which involved the cyclization of polyurea intermediates promoted by acid catalysis. The physical properties of the novel PHYs were evaluated by comparing them with a classical PHY derived from 4,4′-methylenediphenyl diisocyanate. All PHYs were soluble and could be processed into dense films, which showed good mechanical properties (tensile strength up to 110 MPa) and thermal stability of >400 °C. High glass transition temperatures (T gs), ranging from 260 to 410 °C, were observed. Fractional free volume (FFV) was strongly dependent on the chemical structure, and a linear correlation between gas permeability and FFV of PHYs could be found. The gas separation properties were comparable to those of the commercial polyimide Matrimid, with the exception of one of the PHYs which exhibited very promising properties as its gas productivity was comparable to the gas separation performance of well-established experimental polyimides.
