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Polymer derivs

For example, a polypeptide is synthesized as a linear polymer derived from the 20 natural amino acids by translation of a nucleotide sequence present in a messenger RNA (mRNA). The mature protein exists as a weU-defined three-dimensional stmcture. The information necessary to specify the final (tertiary) stmcture of the protein is present in the molecule itself, in the form of the specific sequence of amino acids that form the protein (57). This information is used in the form of myriad noncovalent interactions (such as those in Table 1) that first form relatively simple local stmctural motifs (helix... [Pg.199]

Conductivities of polymers of technological interest such as polypyrrole and polythiophene are typically 1000 cm in the doped state, and the conductivity can be tuned by reversibly doping and undoping the polymer. Derivatives of these and other polymers have achieved even higher conductivities. [Pg.239]

Cuprous salts catalyze the oligomerization of acetylene to vinylacetylene and divinylacetylene (38). The former compound is the raw material for the production of chloroprene monomer and polymers derived from it. Nickel catalysts with the appropriate ligands smoothly convert acetylene to benzene (39) or 1,3,5,7-cyclooctatetraene (40—42). Polymer formation accompanies these transition-metal catalyzed syntheses. [Pg.374]

Binders. Paper-coating biaders are either polymers derived from aatural sources or syathetic polymers. The largest volume, aaturally derived biader is starch (qv) (99). Starch is provided ia derivatized form or unmodified form pead com starch is used predomiaanfly for the latter. Unmodified starch is solubilized by thermal conversion or enzyme conversion. The most common derivatized products are acetylated [9045-28-7] oxidized, and hydroxyethylated starches. [Pg.22]

Hydrogels. Controlled swelling of hydrophilic polymers, derived from the glossy/mbbery properties of polymers, is used to control the rate of dmg release from matrices. In the mbbery state, accompHshed by lowering the polymer s glass-transition temperature to an appropriate level, the dispersed dmg diffuses as the polymer swells in the presence of water. [Pg.231]

Halogenated intermediates, dibromoneopentyl glycol [3296-90-0] (DBNPG), and alkoxylated derivatives of tetrabromobisphenol A are used extensively in flame-retardant apphcations. Similar properties can be derived from halogenated dibasic acids, chlorendic anhydride [115-27-5] (CAN), and tetrabromophthahc anhydride [632-79-1] (TBPA). Processes can be used to produce brominated products by the in situ bromination of polymers derived from tetrahydrophthahc anhydride. [Pg.313]

Mention may finally be made of graft polymers derived from natural rubber which have been the subject of intensive investigation but which have not achieved commercial significance. It has been found that natural rubber is an efficient chain transfer agent for free-radical polymerisation and that grafting appears to occur by the mechanism shown in Figure 30.8. [Pg.865]

Polymer derived from the hydrolysis of polyvinyl esters. [Pg.138]

Schiff s bases also underwent C or N acylation with isocyanates (698) and isothiocyanates (698,701). Further studies provided 2 1 and 2 2 reaction products of arylisothiocyanates and enamines (702) and polymers derived from enamines and bisisocyanates (703). [Pg.399]

Phenol was the 33rd highest-volume chemical. The 1994 U.S. production of phenol was approximately 4 billion pounds. The current world capacity is approximately 15 billion pounds. Many chemicals and polymers derive from phenol. Approximately 50% of production goes to phenolic resins. Phenol and acetone produce bis-phenol A, an important monomer for epoxy resins and polycarbonates. It is produced by condensing acetone and phenol in the presence of HCI, or by using a cation exchange resin. Figure 10-8 shows the Chiyoda Corp. bisphenol A process. [Pg.273]

Petrochemicals in general are compounds and polymers derived directly or indirectly from petroleum and used in the chemical market. Among the major petrochemical products are plastics, synthetic fibers, synthetic ruhher, detergents, and nitrogen fertilizers. Many other important chemical industries such as paints, adhesives, aerosols, insecticides, and pharmaceuticals may involve one or more petrochemical products within their manufacturing steps. [Pg.402]

KJPAC recommendations suggest that polymers derived from I, I-disubstituted monomers CXY=CH (or CH,=CXY) be drawn as lb rather than as la. However, formula la follows logically from the traditional way of writing the mechanism of radical addition (e.g. Scheme 1.1). rtccausc of our focus on mechanism, the style la has been adopted throughout this book. [Pg.2]

The synthesis of three-dimensional polymers derived from T8[OSiMe2H]8 has been also achieved in several ways. For example, by reacting T8[OSiMe2 HJs with bifunctional vinyl-terminated linkers such as (CH2 = CHSiMe2)20, ... [Pg.55]

Whereas conventional poly (amino acids) are probably best grouped together with proteins, polysaccharides, and other endogenous polymeric materials, the pseudopoly (amino acids) can no longer be regarded as "natural polymers." Rather, they are synthetic polymers derived from natural metabolites (e.g., a-L-amino acids) as monomers. In this sense, pseudopoly (amino acids) are similar to polylactic acid, which is also a synthetic polymer, derived exclusively from a natural metabolite. [Pg.197]

As a typical example of topochemically prepared polymers, the nmr speetrum of the polymer derived from ethyl 4-[2-(2-pyrazyl)ethenyl]-cinnamate [l OEt] crystals by reaction (2), and the X-ray diffraction patterns of the same monomer and polymer are illustrated in Figs 1 and 2 (Hasegawa et al., 1989a). [Pg.124]

Eumelanins — These melanins are considered polymers derived from tyrosine derivatives, mainly 5,6-dihydroxyindole-2-carboxylic acid (DHCIA) and dihidrox-yindole (DHl), with high degrees of cross-linking. In vivo eumelanins are associated with proteins and with metals, most frequently copper, zinc, or iron. [Pg.114]

An example of a nonlinear polymer derived by cross-linking an initially linear polymer is afforded by vulcanized natural rubber. In the usual vulcanization procedure involving the use of sulfur and accelerators, various types of cross-linkages may be introduced between occasional units (about one in a hundred) of the polyisoprene chains. Some of these bonds are indicated to be of the following type ... [Pg.33]

ARRANGEMENT OF UNITS IN POLYMERS DERIVED FROM MONOVINYL MONOMERS... [Pg.231]

Branched polymers derived from monomers of the A—B/ i type are discussed here despite the dearth of prominent examples primarily because they occupy a unique intermediate position between linear... [Pg.364]

Euran Furan resins are thermosetting polymers derived from furfuryl alcohol and Furfural. The cure must be carefully controlled to avoid the formation of blisters and delaminations. To obtain optimum strength and corrosion resistance, furan composites must undergo a postcure schedule at carefully selected temperatures depending upon the laminate thickness. Equipment made with furan resins exhibits excellent resistance to solvents and combinations of acids and solvents. These resins are not for use in strong oxidizing environments. [Pg.44]

A dispersant that can be used in drilling fluids, spacer fluids, cement slurries, completion fluids, and mixtures of drilling fluids and cement slurries controls the rheologic properties of and enhances the filtrate control in these fluids. The dispersant consists of polymers derived from monomeric residues, including low-molecular-weight olefins that may be sulfonated or phosphonated, unsaturated dicarboxylic acids, ethylenically unsaturated anhydrides, unsaturated aliphatic monocarboxylic acids, vinyl alcohols and diols, and sulfonated or phosphonated styrene. The sulfonic acid, phosphonic acid, and carboxylic acid groups on the polymers may be present in neutralized form as alkali metal or ammonium salts [192,193]. [Pg.311]


See other pages where Polymer derivs is mentioned: [Pg.23]    [Pg.292]    [Pg.420]    [Pg.421]    [Pg.74]    [Pg.115]    [Pg.417]    [Pg.539]    [Pg.313]    [Pg.369]    [Pg.369]    [Pg.42]    [Pg.6]    [Pg.276]    [Pg.950]    [Pg.613]    [Pg.630]    [Pg.68]    [Pg.92]    [Pg.133]    [Pg.195]    [Pg.103]    [Pg.147]    [Pg.214]    [Pg.418]   


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5-chloroborazine, polymers derived from

Acrylic polymers derivatives

Alkyne derivatives polymers

Amides, from acid derivatives polymers

Amphiphilic polymers with derivatives

Aryl derivatives polymer synthesis

Bilirubin derivatives, polymers

Biodegradable Polymers from Petroleum-Derived Products

Biodegradable polymers petroleum-derived

Biodegradable polymers wood-derived plastics

Borazine polymers derived from

CSPs Derived from Natural Polymers

CSPs Derived from Polymers

CSPs Derived from Synthetic Polymers

Carbohydrate-derived polymers

Carbohydrate-derived polymers, wall

Carbohydrate-derived polymers, wall materials

Charge-transporting polymers structural derivation

Chiral molecules natural polymer derivatives

Cisplatin-derivatives polymers

Conjugated polymers poly derivatives

Ethylene derivatives polymers

Ethylene polymers derived from

Fluorene derived polymers

Fossil fuel-derived polymers

Fullerene Derivatives as Electron Acceptors in Polymer Solar Cells

Functionalised Antimicrobial Polymers Based on Poly(Hydroxystyrene-co-Methyl Methacrylate) Derivatives

Green polymers derivatives

High molecular weight polymers derivatives

Light emitting polymers derivatives

Metathesis Reactions as Tools for the Synthesis of Monomers and Polymers Derived from Vegetable Oils

Microorganism-derived biodegradable polymers

N-Hydroxysuccinimide-Derived Polymers

Natural Products Including Naturally Occurring Polymers and Derivatives

Naturally Derived Cationic Polymers

New Polymers Derived from Chemicals Obtainable by Lignin Decomposition

Norbomene derivatives polymers

Nylon polymers derivatives

Optical activity natural polymer derivatives

Organosilane and conventional organic polymer derived sol-gel coatings

Other polymers of acrylic acid derivatives

Petrochemical-derived polymers

Petroleum-derived products, biodegradable polymers

Phenol-Derived Polymers

Plant-derived polymers, preservation

Plasma derived polymers, properties

Polymer concentration, derivation

Polymer concentration, derivation equations

Polymer derived ceramic

Polymer derived ceramics route

Polymer derived from trichlorophenoxide

Polymer high derived

Polymer nanostructures derivatives

Polymer structure initiator-derived

Polymer supported metal catalysts derivative

Polymer-Supported Boron Derivatives

Polymer-Supported Cinchona Derivatives

Polymer-derived ceramic technology

Polymer-derived ceramics corrosion

Polymer-derived ceramics microstructure

Polymer-derived ceramics oxidation

Polymer-derived ceramics synthesis

Polymer-pyrolysis derived fibers

Polymer-supported derivative

Polymers 5-chloroborazine-derived

Polymers Derived from Unsaturated Carbodiimides

Polymers amine derivatives

Polymers amino acid derivatives

Polymers and Copolymers Derived from Poly(Acrylic Acid)

Polymers borazine-derived

Polymers cinnamic acid derivatives

Polymers derived electrochemically from

Polymers derived from alkylaluminum

Polymers from Thiophen Derivatives

Polymers tris borane-derived

Polymers, radical derivatives

Polysulphonates polymer-derived

Properties of polymer-derived ceramics

Propylene polymers derived from

Rosin polymers derived from

Sol-gel-derived inorganic polymers

Styrene polymers derived from

Tetrafluoroethylene polymers derived from

Thiol-ene Reaction as a Tool for the Synthesis of Monomers and Polymers Derived from Vegetable Oils

Thiol-yne Reaction as a Tool for the Synthesis of Monomers and Polymers Derived from Vegetable Oils

Vinyl chloride polymers derived from

Vinyl polymers with styrene units derivatives

Vinylformamide Derivatives, Polymers Formed Therefrom and Synthesis Thereof

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