Polyurethane-cyclodextrin

Urethane-forming reaction between isocyanate and hydroxyl group was utilized by Osakada et al. to prepare polyurethane-cyclodextrin pseudoro-taxanes (Scheme 15) [86]. Polyaddition of a diol and MDI in the presence of permethylated a-cyclodextrin or permethylated (5-cyclo dextrin was carried out in DMF for 20 h at 120 °C to yield the pseudopolyrotaxane. The molar... 

There are a number of inert binders such as polyester, epoxy, polysulfide, polyurethane which have been reported as binders for composite propellants and plastic bonded explosives (PBXs). At present, hydroxy-terminated polybutadiene (HTPB) is regarded as the state-of-the-art workhorse binder for such applications. However, the recent trend is to use energetic binders such as poly [3,3-bis(azidomethyl oxetane)] [poly(BAMO)], poly (3-azidomethyl-3-methyl oxetane) [poly(AMMO)], PNP, GAP diol and triol, nitrated HTPB(NHTPB), poly(NiMMO), poly(GlyN) and nitrated cyclodextrin polymers poly(CDN) for PBXs and composite propellants in order to get better performance. 

Not only analytical or preparative separations can be performed on cyclodextrin polymer columns, but also undesired components can be removed from aqueous solutions, bitter tasting substances (narin-gin, limonin) can be removed or at least their concentration can be strongly reduced after treatment of citrus juice with cyclodextrin polymers in batch or column process (65,66). Phenylalanine can be eliminated from dietetic protein hydrolysates (67), water-soluble organic substances (e.g. polychlorinated biphenyls (68), 2-naph-talenecarboxylate or phenol can be removed from aqueous solutions (e.g. from pharmaceutical wastewater) by polystyrene-cyclodextrin derivatives (69), by 8-cyclodextrin immobilized on cellulose (70) or by 6-cyclodextrin-polyurethane polymer (71). 

A fascinating self-assembly process is based on the spontaneous threading of cyclodextrins or crown ethers onto polyether polyamine" or polyurethane chains (Figure 5.30). The formed polyrotaxanes possess several cyclodextrin units which are trapped after appropriate capping of the ends. Polymerization of the threaded cyclodextrins and removal of the central thread then leads to molecular cyclodextrane tubules with an inner hydrophobic tunnel and a diameter of about 5 A. 

S.J. Lue and S.H. Peng, Polyurethane (PU) membrane preparation with and without hydroxylpropyl-P-cyclodextrin and their pervaporation characteristics, J. Membr. Sci., 222 (2003) 203-217. 

The synthesis and photochemical reactions of polyurethanes containing [CpFe(CX))2]2 molecules has been examined. Reactions of [CpFe(CX))2Rl, R = alkyl in cyclodextrins with CO and SO2 have been studied. Some cationic ruthenium nitriles, [(Cp)L2Ru(NCAryl)], L = phosphine as phosphite have been prqiared to use in Langmuir-Blodgett films. ... 

Korayem AH, Barati MR, Simon GP, Zhao XL, Duan WH (2014) Relrrforcing brittle and ductile epoxy matrices using carbon nanombes mastmbatch. Compos A Appl Sci Manuf 61 126-133 Kotchey GP, Zhao Y, Kagan VE, Star A (2013) Peroxidase-mediated biodegradation of carbon nanombes in vitro and in vivo. Adv Dmg Deliv Rev 65(15) 1921-1932 Krause RWM, Mamba BB, Dlamini LN, Durbach SH (2010) Fe-Ni nanoparticles supported on carbon nanombe-co-cyclodextrin polyurethanes fm the removal of trichloroethylene in watra-. J Nanopart Res 12(2) 449-456... 

Mases M, Noe M, Mercier G, Dossot M, Vigolo B, Mamane V, Fort Y, Soldatov AV, McRae E (2011) Effects on Raman spectra of functionalisation of single walled carbon nanotubes by nitric acid. Phys Status Solidi (B) Basic Res 248(11) 2552-2555 Masinga SP, Nxumalo EN, Mamba BB, Mhlanga SD (2013) Microwave-induced synthesis of p-cyclodextrin/N-doped caibon nanombe polyurethane nanocomposites for water purification. Phys Chem Earth... 

Li et al. (2007) also described a type of supramolecular shape memory elastomer that contains reversibly associating side groups, namely ureidopyridinone (UPy). In addition to its excellent shape memory effects (SMEs) - about 90% strain fixity and 100% strain recovery - a unique feature of this new SMP is the dynamies of its shape-memory response. More recently, Zhu et al. (2009) synthesized a novel supramolecular polyurethane for utiUzation as a SMP, by grafting the UPy nnit to the elastic polyurethane. Supramolecular SMPs based on o-cyclodextrin (a-CD) network through the inclusion of either PEG or polycaprolactone (PCL) with a-CD. In this system, the a-CD-PEG inclusion crystalhtes and a-CD-PCL crystallites serve as a fixing phase, while the naked PEG crystallites and PCL crystallites act as a reversible phase (Luo et al., 2008 Zhang et al., 2008). Fan... 

Polycyclic aromatic hydrocarbons were also used for imprinting polyurethanes based on Van der Waals interactions, and the resulting MIPs were used for the recognition of the templates [80]. Cholesterol has also been used as the template in the polymeriza-ton of (3-cyclodextrin with diisocyanates in dimethyl sulfoxide [81]. In another work, the vinyl monomer of 6-0-a-D-glucosyl-(3-cyclodextrin was imprinted with dipeptides [82] or cyclodextrin [83]. Other examples include imprinting acryloylamylose with bisphenol A and alkylphenols [84]. 

Another possible approach is based on cyclodextrins, which are bucket-shaped molecules composed of six to eight glucose units and are enzymatically derived from starch. They have the capability of building protective complexes with a variety of molecules, including cosmetically relevant ones such as menthol and vitamin E. These complexes can be attached to fabrics with the help of an adhesive or a binder, which includes cross-linkable silicones, polyacrylates, polyethylene-vinyl acetate, and polyurethanes. A certain amount of binder, typically 0.25-4.0% of dry matter per weight of fabric, is required to bind the microcapsules, complexes, or loaded particles effectively to the medical textile materials. 

Adams FV. Polysulfone/p-cyclodextrin polyurethane mixed-matrix composite nanofiltration membrane for water treatment. PhD Thesis, University of Johannesburg 2013. 

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