480430-52-2Relevant academic research and scientific papers
Poly[(side-on mesogen)-Alt-(end-on mesogen)]: A compromised molecular arrangement
Wang, Meng,Bao, Wei-Wei,Chang, Wen-Ying,Chen, Xu-Man,Lin, Bao-Ping,Yang, Hong,Chen, Er-Qiang
, p. 5791 - 5800 (2019/08/26)
In recent years, sequence-controlled side-chain liquid crystal polymers (SCLCPs) have gained extensive interest because mesogenic units with different lengths and distributions can form various ordered sequences, which further endow LCP materials with diverse functions. In this manuscript, a side-chain side-on maleimide-containing monomer 2,5-bis-(4-butoxy-benzoyloxy)-benzoic acid 6-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-hexyl ester (Y1801) and a side-chain end-on styrene-containing monomer 4′-[6-(4-vinyl-phenoxy)-hexyloxy]-biphenyl-4-carbonitrile (Y1802) are combined in one single macromolecular chain and orderly polymerized in an alternative sequence to form an alternating copolymer Poly(Y1801-Alt-Y1802). The chemical structure and alternating sequence of Poly(Y1801-Alt-Y1802) are confirmed by GPC and NMR techniques. The combination of DSC, POM, and WAXS data indicates that, although the side-on homopolymer PY1801 and the end-on homopolymer PY1802 both exhibit the nematic phase, their alternating copolymer Poly(Y1801-Alt-Y1802) shows an interdigitated smectic A phase, a compromised molecular arrangement instead. In addition, a strong fluorescence emission of Poly(Y1801-Alt-Y1802) is observed, which might provide this novel alternating-structured liquid crystal polymer with potential applications in luminescent materials and devices.
Structure and properties of polymer electrolyte membranes containing phosphonic acids for anhydrous fuel cells
Lee, Sung-Il,Yoon, Kyung-Hwan,Song, Myeongsoo,Peng, Huagen,Page, Kirt A.,Soles, Christopher L.,Yoon, Do Y.
experimental part, p. 115 - 122 (2012/05/20)
Recently, water-free, proton-conducting polymer electrolytes have been attracting attention because of their possible application as fuel cell membranes at intermediate temperatures (100 to 200 °C). Phosphonic acid groups are considered feasible anhydrous proton conducting moieties due to the high degree of proton self-dissociation arising from their intrinsic amphoteric character and high mobility of protonic charge carriers. In this work, we have synthesized and characterized model, phosphonic acid-functionalized proton-conducting polymers, poly(vinylbenzyloxy-alkyl-phosphonic acid)s, for the purpose of exploring the relationship between molecular design, nanostructure, and performance characteristics. These novel proton conducting materials were characterized for their thermal stability, nanostructure, and performance properties. Thermogravimetric analysis (TGA) indicates that the polymers are thermally stable up to 140 °C, where the condensation of phosphonic acid groups starts to occur. Results from small-angle X-ray scattering (SAXS) show a peak corresponding to a Bragg spacing of approximately 21-24 A, which is attributed to layerlike structure formation of the phosphonic acid containing conducting channels. The proton conductivity increases with temperature, reaching a value on the order of 3 × 10-4 S/cm at 140 °C under nominally anhydrous conditions.
Polymer-supported protic functionalized ionic liquids for nucleophilic substitution reactions: superior catalytic activity compared to other ionic resins
Shinde, Sandip S.,Lee, Byoung Se,Chi, Dae Yoon
, p. 4245 - 4248 (2008/09/21)
Three polymer-supported quaternary ammonium mesylates were synthesized for recyclable polymeric phase transfer catalysts (PTCs). Through comparison study using nucleophilic fluorination, tertiary alcohol containing polymer 3c proved to be the best catalys
Polymeric boronic acid derivatives as lipase inhibitors
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Page/Page column 14, (2010/11/08)
Human obesity is a health problem affecting a significant proportion of the American population. Numerous methods of treating obesity have been developed, but all have serious drawbacks. The present invention discloses a novel class of polymers with eithe
Styrene-containing mesogens. Part 1: Photopolymerisable nematic liquid crystals
Cook, Anthony,Badriya, Samer,Greenfield, Simon,McKeown, Neil B.
, p. 2675 - 2683 (2007/10/03)
Several members of a novel series of styrene-containing liquid crystal monomers, based on the cyanobiphenyl mesogenic group, possess thermally stable nematic phases. These materials display a large odd-even effect, relating to the length of the flexible spacer between the styrene and cyanobiphenyl units, which is very similar to previously described liquid crystal 'dimers' composed of two cyanobiphenyl units. It is shown that styrene (i.e. 4-vinylphenoxy) is an excellent terminal group for cyanobiphenyl mesogens as compared to a number of other phenyloxy groups. In addition, a compatible bifunctional mesogenic crosslinker is described. Photopolymerisation of an aligned film of a low-melting eutectic mixture derived from these compounds is achieved using cationic initiation in aerobic conditions.
