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Poly adducts

A similar procedure was used for the heparinization of block copolymers composed of the poly-adduct of N,N -dimethyl-ethylenediamine and 1,4-bisacryloylpiperidine as a central block and of polystyrene as the end blocks 82). To enhance the stability of the material, heparin was crosslinked with glutaric dialdehyde. The resultant HCP sustained a 6 month implantation into the dog s vena cava. [Pg.109]

To clarify that the obtained polymer was a true poly adduct but not a vinyl polymer, H NMR analysis of the polymer was carried out (Fig. 1). Using VSB, DAO and poly(silamine) I (see Fig. 2) as reference compounds, the assignments of the signals were carried out and described in the figure. Around 2.4 - 2.5 ppm, multiplet signals assignable... [Pg.280]

Ionic polymers are also formulated from TDI and MDI (43). Poly(urethane urea) and polyurea ionomers are obtained from divalent metal salts of /)-aminohen2oic acid, MPA, dialkylene glycol, and 2,4-TDI (44). In the case of polyureas, the glycol extender is omitted. If TDI is used in coatings apphcations, it is usually converted to a derivative to lower the vapor pressure. A typical TDI prepolymer is the adduct of TDI with trimethyl olpropane (Desmodur L). Carbodiimide-modified MDI offers advantages in polyester-based systems because of improved hydrolytic stabihty (45). Moisture cure systems based on aromatic isocyanates are also available. [Pg.350]

Ethers, esters, amides and imidazolidines containing an epithio group are said to be effective in enhancing the antiwear and extreme pressure peiformance of lubricants. Other uses of thiiranes are as follows fuel gas odorant (2-methylthiirane), improvement of antistatic and wetting properties of fibers and films [poly(ethyleneglycol) ethers of 2-hydroxymethyl thiirane], inhibition of alkene metathesis (2-methylthiirane), stabilizers for poly(thiirane) (halogen adducts of thiiranes), enhancement of respiration of tobacco leaves (thiirane), tobacco additives to reduce nicotine and to reduce phenol levels in smoke [2-(methoxymethyl)thiirane], stabilizers for trichloroethylene and 1,1,1-trichloroethane (2-methylthiirane, 2-hydroxymethylthiirane) and stabilizers for organic compounds (0,0-dialkyldithiophosphate esters of 2-mercaptomethylthiirane). The product of the reaction of aniline with thiirane is reported to be useful in the flotation of zinc sulfide. [Pg.184]

Hydroxy-containing polymers such as poly(methyl-methacrylate-co-hydroxyethyl methacrylate) [65,66] or secondary cellulose acetate [67,68] were used for this purpose. Vanadium (V) 8-hydroxy quinoline-hydroxy-ethyl methacrylate adduct, prepared by condensation of the latter with a VOQ2OH complex, is polymerized to... [Pg.256]

Pyridinium ylide is considered to be the adduct car-bene to the lone pair of nitrogen in pyridine. The validity of this assumption was confirmed by Tozume et al. [12J. They obtained pyridinium bis-(methoxycarbonyl) meth-ylide by the photolysis of dimethyl diazomalonate in pyridine. Matsuyama et al. [13] reported that the pyridinium ylide was produced quantitatively by the transylidalion of sulfonium ylide with pyridine in the presence of some sulfides. However, in their method it was not easy to separate the end products. Kondo and his coworkers [14] noticed that this disadvantage was overcome by the use of carbon disulfide as a catalyst. Therefore, they used this reaction to prepare poly[4-vinylpyridinium bis-(methoxycarbonyl) methylide (Scheme 12) by stirring a solution of poly(4-vinylpyridine), methylphenylsulfo-nium bis-(methoxycarbonyl)methylide, and carbon disulfide in chloroform for 2 days at room temperature. [Pg.375]

We have also used poly(propynoic acid) in our studies of the photochemical interaction of PCSs with dienophiles, such as maleic anhydride, tetracyanoethylene, and styrene. This photochemical reaction of Diels-Alder type is accompanied by the breakdown of the conjugation system and the formation of slightly colored adducts266. Together with the cycloaddition reaction, photodegradation of PPA and its adducts takes place. A cycloaddition reaction is always preceded by the formation of a donor-acceptor complex of a PCS with a dienophile. [Pg.31]

Whereas nonionic ethylene oxide adducts discolor badly on contact with sodium hydroxide, phosphate derivatives of these nonionics exhibit good color stability even under these conditions. But in the presence of strong acids poly-oxyethylated phosphate esters undergo hydrolysis to the base nonionic and phosphoric acid. However, the free surface-active acids by themselves show little tendency to hydrolyze. They have a pH value of 2 in aqueous solution. [Pg.564]

Silyl radicals generated from both phenyl and n-hexyl substituted poly-(hydrosilane)s add readily to a variety of compounds containing C = C and 0 = C moieties to give the corresponding radical adducts for which EPR spectra have been recorded. ... [Pg.161]

J. C. Cowan, V. M. Granquist, and R. F. House. Organophilic poly-phenolic acid adducts. Patent US 4737295, 1988. [Pg.374]

Figure 18 Syntheses of poly(phenylphosphinoborane) [PhPH-BH2] (25) and poly(isobutylphosphinoborane) p -BuPH-BH2]K (26) from their respective phosphane-borane adducts. (Adapted from ref. 45.)... Figure 18 Syntheses of poly(phenylphosphinoborane) [PhPH-BH2] (25) and poly(isobutylphosphinoborane) p -BuPH-BH2]K (26) from their respective phosphane-borane adducts. (Adapted from ref. 45.)...
A radical initiator based on the oxidation adduct of an alkyl-9-BBN (47) has been utilized to produce poly(methylmethacrylate) (48) (Fig. 31) from methylmethacrylate monomer by a living anionic polymerization route that does not require the mediation of a metal catalyst. The relatively broad molecular weight distribution (PDI = (MJM ) 2.5) compared with those in living anionic polymerization cases was attributed to the slow initiation of the polymerization.69 A similar radical polymerization route aided by 47 was utilized in the synthesis of functionalized syndiotactic polystyrene (PS) polymers by the copolymerization of styrene.70 The borane groups in the functionalized syndiotactic polystyrenes were transformed into free-radical initiators for the in situ free-radical graft polymerization to prepare s-PS-g-PMMA graft copolymers. [Pg.41]

Figure 31 The radical initiator (47) based on the oxidation adduct of an alkyl-9-BBN used for the production of poly(methyhnethacrylate) (48) from methylmethacrylate monomer by the radical polymerization route. (Adapted from ref. 69.)... Figure 31 The radical initiator (47) based on the oxidation adduct of an alkyl-9-BBN used for the production of poly(methyhnethacrylate) (48) from methylmethacrylate monomer by the radical polymerization route. (Adapted from ref. 69.)...
The HLB of a relatively pure poly(oxyethylene) adduct can be calculated from theoretical data [37]. For these agents the HLB is an indication of percentage by mass of the hydrophilic portion, divided by five to give a conveniently small number. For example, if the hydrophilic portion of a purely hypothetical nonionic agent accounted for 100% of the molecule (such a product cannot, of course, exist), its HLB is 20. Similarly, a more plausible product in which 85% of the molecule is accounted for by the hydrophilic portion has an HLB of 85/5 = 17. The ICI Americas Inc. method of calculating the theoretical HLB of a sorbitan monolaurate nonionic having 20 oxyethylene units per molecule is given in... [Pg.30]


See other pages where Poly adducts is mentioned: [Pg.54]    [Pg.129]    [Pg.748]    [Pg.54]    [Pg.129]    [Pg.748]    [Pg.49]    [Pg.30]    [Pg.463]    [Pg.182]    [Pg.664]    [Pg.332]    [Pg.68]    [Pg.156]    [Pg.178]    [Pg.59]    [Pg.559]    [Pg.161]    [Pg.596]    [Pg.70]    [Pg.249]    [Pg.256]    [Pg.434]    [Pg.110]    [Pg.929]    [Pg.973]    [Pg.32]    [Pg.32]    [Pg.37]    [Pg.25]    [Pg.267]    [Pg.179]    [Pg.209]    [Pg.822]    [Pg.871]    [Pg.149]    [Pg.53]    [Pg.63]   
See also in sourсe #XX -- [ Pg.164 , Pg.165 , Pg.166 , Pg.167 , Pg.168 , Pg.171 ]




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