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Amine poly complexes

The hemocompatibility of poly(amido-amine) polyelectrolyte complexes was recently studied by Xi, Zhang and coworkers [499, 500]. The poly(amido-amine) was based on piperazine and methylene bisacrylamide, and the polyelectrolyte complexes were obtained from the reaction of poly(amido-amine) with alginic acid, carboxymethyl cellulose or poly(methacrylic acid). Complexes of polyamido-amine and alginic acid with a 1 2 ratio gave the best hemocompatibility. Finally, the blood compatibility of polyelectrolyte complexes based on anionic and cationic cellulose derivatives were studied by Ito et al. [338], In vivo, good blood compatibility of complexes formed from quaternary hy-droxyethyl cellulose reacted with carboxymethyl cellulose and cellulose sulfate was observed. [Pg.42]

Studies on the immobilization of Pt-based hydrosilylation catalysts have resulted in the development of polymer-supported Pt catalysts that exhibit high hydrosilylation and low isomerization activity, high selectivity, and stability in solventless alkene hydrosilylation at room temperature.627 Results with Rh(I) and Pt(II) complexes supported on polyamides628 and Mn-based carbonyl complexes immobilized on aminated poly(siloxane) have also been published.629 A supported Pt-Pd bimetallic colloid containing Pd as the core metal with Pt on the surface showed a remarkable shift in activity in the hydrosilylation of 1-octene.630... [Pg.344]

Pyridinium poly(hydrogen fluoride) (PPHF), which serves as an HF equivalent catalyst with decreased volatility,159 showed similar characteristics in liquid CO2.158 Other liquid amine poly (hydrogen fluoride) complexes with high (22 1) HF/amine ratios are also effective catalysts in the alkylation of isobutane with butenes and, at the same time, also act as ionic liquid solvents.160 Likewise the solid poly(ethyleneimine)/ HF and poly(4-vinylpyridinium)/HF (1 24) complexes have proved to be efficient catalysts affording excellent yields of high-octane alkylates with research octane numbers up to 94. [Pg.551]

Ishizu et al.194 synthesized hyperbranched macromolecules that resemble dendrimers. The synthetic approach involved the preparation of poly(4-methyl-styrene-b-PS-b-poly(4-methylstyrene) triblock copolymer by using naphthalene lithium as difunctional initiator. The 4-methyl groups of the terminal blocks were metalated with s-BuLi/tetramethylethylenedi-amine (TMEDA) complex in a molar ratio of 1 2. After removal of the excess s-BuLi by repeated precipitation of the living polymer and transfer of supernatant solution to another flask under high vacuum conditions, the polymer was dissolved in THF and was used as the initiator of a-methylstyrene at —78 °C. After the polymerization of a-methylstyrene, a small amount of 4-methylstyrene was added. The procedure of metalation of the a-methyl groups and polymerization of a-methylstyrene can be repeated many times to form a dendritic type hyperbranched polymer (Scheme 99). The characterization of the inter-... [Pg.607]

Olah GA, Mathew T, Goeppert A et al (2005) Ionic liquid and solid HF equivalent amine-poly(hydrogen fluoride) complexes effecting efficient environmentally friendly isobutane-isobutylene alkylation. J Am Chem Soc 127 5964—5969... [Pg.30]

Aminoalcohols more strongly complex with carboxylic acid than amines. This characteristic allows substitution of the chiral amines, initially complexed with poly(4-carboxylphenylacetylene), by achiral aminoalcohols (260). The most... [Pg.32]

An example of the use of conductance to estimate the complex stoichiometry is illustrated in Fig. 4.27 for poly(vinyl amine)/poly(acrylic acid) (PVAm/PAA). The minimum in conductance depends on the formation of the complex. In the forward curve, PAA was added at predetermined increments to a PVAm solution, followed by 60 s stirring and conductance measurements. The reverse curve involved PVAm addition to a PAA solution. The minimum in conductance depends on the path chosen to prepare the complexes, indicating that tmcom-plexed polymer maybe trapped during the polyelectrolyte complex phase separation process. As the minimum points are on both sides of the equimolar position, this complex appears to be equimolar. [Pg.193]

The protonated form of poly(vinyl amine) (PVAm—HCl) has two advantages over many cationic polymers high cationic charge densities are possible and the pendent primary amines have high reactivity. It has been appHed in water treatment, paper making, and textiles (qv). The protonated forms modified with low molecular weight aldehydes are usehil as fines and filler retention agents and are in use with recycled fibers. As with all new products, unexpected appHcations, such as in clear antiperspirants, have been found. It is usehil in many metal complexation appHcations (49). [Pg.320]

Trilialophenols can be converted to poly(dihaloph.enylene oxide)s by a reaction that resembles radical-initiated displacement polymerization. In one procedure, either a copper or silver complex of the phenol is heated to produce a branched product (50). In another procedure, a catalytic quantity of an oxidizing agent and the dry sodium salt in dimethyl sulfoxide produces linear poly(2,6-dichloro-l,4-polyphenylene oxide) (51). The polymer can also be prepared by direct oxidation with a copper—amine catalyst, although branching in the ortho positions is indicated by chlorine analyses (52). [Pg.330]

The oxidative coupling of 2,6-dimethylphenol to yield poly(phenylene oxide) represents 90—95% of the consumption of 2,6-dimethylphenol (68). The oxidation with air is catalyzed by a copper—amine complex. The poly(phenylene oxide) derived from 2,6-dimethylphenol is blended with other polymers, primarily high impact polystyrene, and the resulting alloy is widely used in housings for business machines, electronic equipment and in the manufacture of automobiles (see Polyethers, aromatic). A minor use of 2,6-dimethylphenol involves its oxidative coupling to... [Pg.69]

Thus, most ionic liquids are formed from cations that do not contain acidic protons. A summary of the applications and properties of ionic liquids may be found in a number of recent review articles [3]. The most common classes of cations are illustrated in Figure 2.1-1, although low melting point salts based on other cations, such as complex poly cationic amines [4] and heterocycle-containing drugs [5], have also been prepared. [Pg.8]

The mechanism of the polymerization of NCA with tertiary amine is still controversial. Mori and Iwatsuki claim that the true initiator is the primary amino group formed by hydrolysis of the NCA with contaminated water and that tertiary amine forms a complex with the NCA and accelerates the addition reaction37 . Harwood et al. confirmed the propagating carbamate by NMR in polymerization initiated with a strong base37 . The successive addition of NCA to the polymer end catalyzed with a strong base affords an alternative procedure for the synthesis of block copolypeptides. Block copolypeptides of poly(oxyethylene) were prepared by triethyl amine catalyzed polymerization of NCA in the presence of poly(oxyethylene)bis-eMoroformate38 . [Pg.33]

A great variety of suitable polymers is accessible by polymerization of vinylic monomers, or by reaction of alcohols or amines with functionalized polymers such as chloromethylat polystyrene or methacryloylchloride. The functionality in the polymer may also a ligand which can bind transition metal complexes. Examples are poly-4-vinylpyridine and triphenylphosphine modified polymers. In all cases of reactively functionalized polymers, the loading with redox active species may also occur after film formation on the electrode surface but it was recognized that such a procedure may lead to inhomogeneous distribution of redox centers in the film... [Pg.53]

It has been found that DTBP cross-linking substantially increased the salt stability of the complexes. The salt stabilization is reversed upon the addition of DTT, which cleaves the bifunctional reagent, indicating that it is not due to the conversion of the amines to amidines and is dependent upon the cross-linking. Similar results were achieved with other polycations, including poly(allylamine), and histone HI. [Pg.448]

Metal-acetylide complexes have been used as a unit of organometallic polymers that have metallic species in the main chain [20]. Representative examples are metal-poly(yne) polymers (19) of group 10 metals depicted in Scheme 5. These polymers are easily prepared from M(PR3)2Cl2 (M=Pt, Pd) and dialkynyl compounds catalyzed by Cu(I) salts in amine. Recently, this synthetic method was successfully applied to the construction of metal-acetylide dendrimers. [Pg.47]

The effect of pH and cation concentration on pectinesterase (PE) activation and permeation on 30 kD MWCO ultrafiltration (UF) membrane was evaluated. In order of increasing effectiveness, PE activity was stimulated by monovalent and divalent cations, poly amines and trivalent cations. A similar trend was observed for permeation on UF membranes. Cation addition and higher pH releases PE from an inactive complex, increases activity, and increases permeation. Higher cation concentration decreases activity and permeation. These results suggest a common mechanism is involved in PE activation and permeation. [Pg.475]

Plasticiser/oil in rubber is usually determined by solvent extraction (ISO 1407) and FTIR identification [57] TGA can usually provide good quantifications of plasticiser contents. Antidegradants in rubber compounds may be determined by HS-GC-MS for volatile species (e.g. BHT, IPPD), but usually solvent extraction is required, followed by GC-MS, HPLC, UV or DP-MS analysis. Since cross-linked rubbers are insoluble, more complex extraction procedures must be carried out. The determination of antioxidants in rubbers by means of HPLC and TLC has been reviewed [58], The TLC technique for antidegradants in rubbers is described in ASTM D 3156 and ISO 4645.2 (1984). Direct probe EIMS was also used to analyse antioxidants (hindered phenols and aromatic amines) in rubber extracts [59]. ISO 11089 (1997) deals with the determination of /V-phenyl-/9-naphthylamine and poly-2,2,4-trimethyl-1,2-dihydroquinoline (TMDQ) as well as other generic types of antiozonants such as IV-alkyl-AL-phenyl-p-phenylenediamines (e.g. IPPD and 6PPD) and A-aryl-AL-aryl-p-phenylenediamines (e.g. DPPD), by means of HPLC. [Pg.35]

In an acetone extract from a neoprene/SBR hose compound, Lattimer et al. [92] distinguished dioctylph-thalate (m/z 390), di(r-octyl)diphenylamine (m/z 393), 1,3,5-tris(3,5-di-f-butyl-4-hydroxybenzyl)-isocyanurate m/z 783), hydrocarbon oil and a paraffin wax (numerous molecular ions in the m/z range of 200-500) by means of FD-MS. Since cross-linked rubbers are insoluble, more complex extraction procedures must be carried out (Chapter 2). The method of Dinsmore and Smith [257], or a modification thereof, is normally used. Mass spectrometry (and other analytical techniques) is then used to characterise the various rubber fractions. The mass-spectral identification of numerous antioxidants (hindered phenols and aromatic amines, e.g. phenyl-/ -naphthyl-amine, 6-dodecyl-2,2,4-trimethyl-l,2-dihydroquinoline, butylated bisphenol-A, HPPD, poly-TMDQ, di-(t-octyl)diphenylamine) in rubber extracts by means of direct probe EI-MS with programmed heating, has been reported [252]. The main problem reported consisted of the numerous ions arising from hydrocarbon oil in the recipe. In older work, mass spectrometry has been used to qualitatively identify volatile AOs in sheet samples of SBR and rubber-type vulcanisates after extraction of the polymer with acetone [51,246]. [Pg.411]

Reduction of Poly(2-cyano-l,3-phenylene arylene ether), 20 Twenty-five mL of a 1.0 M solution of lithium aluminum hydride (LAH) in THF was cooled to 0° C before adding a solution of 1.64 g (5.0 meg) of 20 in 120 mL of THF. The resultant slurry was stirred for 24 h at 0° C, refluxed for 1 h, recooled to 5° C, and the excess LAH decomposed with 2 mL of water. The volume of the solution was reduced to 25 mL before pouring the mixture into 500 mL of 5% HC1 to dissociate the amine aluminum salt complex and precipitate the polymer. The polymer was recovered by filtration, reslurried in 20 mL of water and the pH adjusted to 9.0 with NaOH. After recovery of the neutralized polymer was recovered, it was dried in vacuo redissolved in CHC13, and reprecipitated using water as the nonsolvent. Final drying in vacuo for 24 h at 35° C left 1.2 g (72.3%) of poly[oxy-l,4-phenylene-(l-methylethylidene)-l, 4 -phenylene-oxy-(2"-aminomethyl)-l",3"-phenylene], 21, [n] (CHCI3) 0.3 dl/g. [Pg.13]

K Ishihara, M Kobayashi, N Ishimaru, I Shinohara. Glucose induced permeation control of insulin through a complex membrane consisting of immobilized glucose oxidase and a poly(amine). Polym J 8 625-631, 1984. [Pg.584]

As a further approach for novel electrolytes appropriate for selective cation transport, we have prepared poly(organoboron halide)-imidazole complexes.35 Even though boron-amine complexes are widely known materials reported by the early works of H. C. Brown et al.,52-54 they had not been investigated as solvents or electrolytes to the best of our knowledge. [Pg.200]


See other pages where Amine poly complexes is mentioned: [Pg.153]    [Pg.66]    [Pg.323]    [Pg.49]    [Pg.1297]    [Pg.146]    [Pg.161]    [Pg.47]    [Pg.111]    [Pg.54]    [Pg.61]    [Pg.158]    [Pg.100]    [Pg.122]    [Pg.624]    [Pg.634]    [Pg.156]    [Pg.8]    [Pg.168]    [Pg.59]    [Pg.639]    [Pg.228]    [Pg.99]    [Pg.432]    [Pg.261]    [Pg.25]   


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Amines complexes

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Poly amines

Poly complexity

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