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Monomer acid derivatives

Flammability. Dimer and trimer acids, as well as monomer acids derived from dimer acid processing, are neither flammable nor combustible as defined by the Department of Transportation (DOT) and do not represent a fire ha2ard ... [Pg.117]

Tall Oil Fatty Acid derivatives to make monomer acid derivatives. Because the monomer acid derivatives had not been made during the initial Inventory reporting period they did not qualify for an Inventory correction. Instead, the EP A announced that it would delay the effective date of its new interpretation for one year, during which time affected industry members could file PMNs for monomer acid derivatives. ... [Pg.63]

Photopolymerizable compositions based on monomeric acryflc or other ethylenicaHy unsaturated acid derivatives are becoming increasingly popular. When multiftmctional derivatives are employed, three-dimensional networks having high strength and abrasion resistance are possible on exposure to light. A typical composition may contain an ethoxylated trimethylolpropane triacrylate monomer, a perester phenacjhdene initiator (69), and an acryflc acid—alkyl methacrylate copolymer as binder. [Pg.44]

In the case of electron-deficient monomers (e.g, acrylics) it is accepted that reaction occurs by initial addition of the sulfate radical anion to the monomer. Reactions of sulfate radical anion with acrylic acid derivatives have been shown to give rise to the sulfate adduct under neutral or basic conditions but under acidic conditions give the radical cation probahly by an addition-elimination process. [Pg.129]

A nomenclature was proposed by Seebach for the description of / -amino acids according to their substitution pattern, and for naming the resulting / -peptides [66, 67]. Enantiomerically pure / -amino acid derivatives with substituents in the 2-or 3-position are thus defined as - and / -amino acids, respectively (abbreviated to H-/ -HXaa-OH and H-/ -HXaa-OH). The corresponding /S-peptides built from these monomers will be named ff - and / -peptides. Similarly, /S -peptides consist of / -amino acid residues with substituents in both the 2- and 3-positions. Finally, peptides built from geminally disubsituted amino acids are referred to as and / -peptides (Fig. 2.6). [Pg.40]

Laccase (PCL) as well as peroxidases (HRP and SBP) induced a new type of oxidative polymerization of the 4-hydroxybenzoic acid derivatives, 3,5-dimethoxy-4-hydroxybenzoic acid (syringic acid) and 3,5-dimethyl-4-hydroxybenzoic acid. The polymerization involved elimination of carbon dioxide and hydrogen from the monomer to give PPO derivatives with molecular weight up to 1.8 x lO (Scheme 22). - ... [Pg.233]

Poly(3HAMCL)s have also been produced from free fatty acid mixtures derived from industrial by-products which are potentially interesting low-cost renewable resources. Isolation and analysis of the polymer allowed the identification of 16 different saturated, mono-unsaturated and di-unsaturated monomers [46]. Except for the presence of diene-containing monomers and a large number of minor components, the composition of the fatty acid mixture derived PHA did not differ significantly from oleic acid derived PHAs. [Pg.168]

Various combinations of dicarboxylic acid derivatives and glycols enzymatically afforded polyesters under mild reaction conditions. Dicarboxylic acids as well as derivatives, activated and non-activated esters, cyclic acid anhydride, and polyanhydrides, were found to be useful as monomer for the enzymatic synthesis of polyesters. [Pg.242]

WIN 64821 (10) and (—)-ditryptophenaline (11) syntheses [7], not only effectively differentiated the two amide moieties but also most importantly marked the first in a series of stereochemical transfer steps in which the stereochemistry of the constituent L-amino acids was relayed to ultimately define each of the relative and absolute stereochemical configurations at all eight stereogenic centers found in the target compound. Finally, /V-methylation of the base-sensitive amide in 77 % yield using methyl iodide and potassium carbonate in acetone completed the 5-step synthesis of our key tetracyclic bromide monomer starting from commercially available amino acid derivatives. [Pg.224]

Many polymers have been studied for their usefulness in producing pharmacologically active complexes with proteins or drugs. Synthetic and natural polymers such as polysaccharides, poly(L-lysine) and other poly(amino acids), poly(vinyl alcohols), polyvinylpyrrolidinones, poly(acrylic acid) derivatives, various polyurethanes, and polyphosphazenes have been coupled to with a diversity of substances to explore their properties (Duncan and Kopecek, 1984 Braatz et al., 1993). Copolymer preparations of two monomers also have been tried (Nathan et al., 1993). [Pg.936]

Polyanhydrides from Unsaturated and Fatty Acid-derived Monomers... [Pg.177]

Polyanhydrides based on unsaturated and fatty acid-derived monomers are shown in Table III. Poly(fumaric acid) (PFA) was fist synthesized by Domb et al. (1991) by both melt polycondensation and solution polymerization. The copolymer of fumaric acid and sebacic acid (P(FA-SA)) has been synthesized and characterized (Domb et al., 1991 Mathiowitz et al., 1990b). The mucoadhesive properties of this polymer... [Pg.177]

The polymer-supported chiral phosphine obtained (Fig. 42.15) was treated with an Rh precursor and used for the enantioselective hydrogenation of dehydroamino acid derivatives. The obtained catalyst gave up to 82% ee, albeit with still low activity. Stille has developed this immobilization technique further by even more careful tuning of the polarity of the support with that of the reaction medium. For example, he introduced DIOP to a monomer vinylbenzalde-hyde in reactions analogous to those shown for the polymer in Figure 42.11. [Pg.1448]

Interest in new solid polymer electrolytes has driven some research groups to investigate other materials containing proton conducting moieties aside from sulfonic acid. Polymers and copolymers from monomers containing phosphonic-based proton conductors have been reported. Phosphonic and/or phosphinic acid containing polymers have not been well studied because of the rather limited synthetic procedures available for their preparation, compared with sulfonic acid derivatives. Miyatake and Hay... [Pg.366]

Later, Tieke reported the UV- and y-irradiation polymerization of butadiene derivatives crystallized in perovskite-type layer structures [21,22]. He reported the solid-state polymerization of butadienes containing aminomethyl groups as pendant substituents that form layered perovskite halide salts to yield erythro-diisotactic 1,4-trans polymers. Interestingly, Tieke and his coworker determined the crystal structure of the polymerized compounds of some derivatives by X-ray diffraction [23,24]. From comparative X-ray studies of monomeric and polymeric crystals, a contraction of the lattice constant parallel to the polymer chain direction by approximately 8% is evident. Both the carboxylic acid and aminomethyl substituent groups are in an isotactic arrangement, resulting in diisotactic polymer chains. He also referred to the y-radiation polymerization of molecular crystals of the sorbic acid derivatives with a long alkyl chain as the N-substituent [25]. More recently, Schlitter and Beck reported the solid-state polymerization of lithium sorbate [26]. However, the details of topochemical polymerization of 1,3-diene monomers were not revealed until very recently. [Pg.267]

Table 2 Monomer stacking parameters for the crystals of topochemically polymerizable 1,3-diene mono- and dicarboxylic acid derivatives [16] ... Table 2 Monomer stacking parameters for the crystals of topochemically polymerizable 1,3-diene mono- and dicarboxylic acid derivatives [16] ...
A second route (route B in Fig. 1) relies on an initiation process with an (meth)acryl hydroxyl compound and is adopted from the chemical ROP of lactones. The controlled character of these polymerizations ensures a virtually quantitative initiation and thus incorporation of hydroxy-functional initiator (e.g., acrylate) into the polymer chain. However, this is not automatically the case for lipase-catalyzed ROP due to the different mechanism. The latter follows an activated monomer mechanism in which the lipase activates any carbonyl group of a carboxylic acid derivative present in the system. It has recently been shown that acrylation using hydroxy-functional acrylate initiators like hydroxy ethyl(meth)acrylate (HEMA or... [Pg.82]

Due to the vast numbers and rapidity of novel developments in solid-phase synthesis over the past ten years, a number of reports currently found in the literature deal with solid-phase syntheses of lanthionine peptides. There are at least two different approaches to synthesize lanthionine peptides in which the sulfide bond links amino acid halves that are not direct neighbors within the peptide chain (Scheme 10). One obvious approach, method A, is based on the coupling of a preformed, orthogonally protected lanthionine monomer to the N-terminus of a peptide oxime resin. 48 This is then followed by acid-catalyzed cyclization and simultaneous release from the resin during amide bond formation with the C-terminal carboxy group via the peptide cyclization method on oxime resin (see Section 6.73.2.2). The alternative approach is lanthionine formation after peptide synthesis from amino acid derivatives, such as serine and cysteine (method B). [Pg.193]


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See also in sourсe #XX -- [ Pg.63 ]




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