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Terminal functional group

Poly (ary lene ether sulfone)s and poly(arylene ether ketone) have been employed to prepare block and graft copolymers. Generally, the block copolymers can be prepared by reacting functional-group-terminated oligomers with other functional oligomers and monomers. [Pg.359]

Pd(ll) catalysts can be employed as well. Compared to the standard Pd(ll) catalysts, the palladacycle catalyst 7 shows a broader compatibility with functional groups. Terminal alkynes, alkyl halides, and a-halogen ketones are tolerated <1997CB1449>. It is worth mentioning that other catalysts of Pd(ll) preferentially give dimerization products. [Pg.502]

The cyclization-dimerisation of allenylketones 29 to furans 28 and/or 2,4-disubstituted furans 30 is well known. By making the choice of either PdCl2(MeCN)2 or rac-31 as catalyst, the allenylketones 29 could be preferentially converted into 28 or 30. Since the catalyst tolerates several functional groups (terminal alkynes, a-halogenketones, alkyl halides) this catalyst is an important improvement of Marshall s Ag(l)-catalyzed isomerisation of 29 to 28 <97CB1449 97CB1457>. [Pg.138]

Carboalumination of alkynes is possible in the presence of the zirconium catalyst Cp2ZrCl2. The method is particularly attractive for methylalumination using Me3 A1 and can tolerate a wide variety of functional groups. Terminal alkynes react with very good regioselectivity ( 95 5) and excellent stereoselectivity (>98%) in favour of the alkenyl aluminium species, such as 58 (2.69). Mixtures of regioisomers often result when using internal alkynes with two different substituents. [Pg.132]

Polythiophenes present a multitude of color contrasts. These polymers, with a functional group terminal to a flexible alkyl chain at the 3-position of the ring, are used for many specialized applications. One such candidate of this class is poly(3-[12-(/7-methoxyphenoxy)dodecyl]thiophene [poly(12-MPDDT)], synthesized by Ribeiro et al., which exhibited a deposition charge of ca. 65 mCcm" presented greater stability over a large number of redox cycles (> 1000), a chromatic contrast of 40 % at 725 nm, a Coulombic efficiency of 80 % and good optical memory in the neutral state (E = 0.0 V) [15]. [Pg.772]

Besides the above-mentioned coating systems, functional group terminated prepolymers based on acrylics, polyurethanes and alkyds can also be used as curing agents to obtain coating systems with tailor-made performance requirements. Recently, a few HS coatings formulations based on epoxy resins have been reported in the literature. " ... [Pg.960]

For molecules similar to safrole or allylbenzene we take the work done on any terminal alkene such as 1-heptene, 1 octene. Another term to look for is olefin which is a term for a doublebond containing species. What we then look for are articles about these olefins where the functional groups we are looking for are formed. Articles with terminology like methyl ketones from (P2P), ketones from , amines from etc. Or when we want to see about new ways to aminate a ketone (make final product from P2P) we look for any article about ketones where amines are formed. Sound like science fiction to you Well, how do you think we came up with half the recipes in this book It works ... [Pg.183]

The oxidation of higher alkenes in organic solvents proceeds under almost neutral conditions, and hence many functional groups such as ester or lac-tone[26,56-59], sulfonate[60], aldehyde[61-63], acetal[60], MOM ether[64], car-bobenzoxy[65], /-allylic alcohol[66], bromide[67,68], tertiary amine[69], and phenylselenide[70] can be tolerated. Partial hydrolysis of THP ether[71] and silyl ethers under certain conditions was reported. Alcohols are oxidized with Pd(II)[72-74] but the oxidation is slower than the oxidation of terminal alkenes and gives no problem when alcohols are used as solvents[75,76]. [Pg.24]

Various butadiene telomers obtained by Pd-calalyzed reactions have one functional group at one end and a terminal and an internal double bond, and they... [Pg.441]

Hydrocarbons that contain a carbon-carbon triple bond are called alkynes Non cyclic alkynes have the molecular formula C H2 -2 Acetylene (HC=CH) is the simplest alkyne We call compounds that have their triple bond at the end of a carbon chain (RC=CH) monosubstituted or terminal alkynes Disubstituted alkynes (RC=CR ) have internal triple bonds You will see m this chapter that a carbon-carbon triple bond is a functional group reacting with many of the same reagents that react with the double bonds of alkenes... [Pg.363]

Antioxidants markedly retard the rate of autoxidation throughout the useful life of the polymer. Chain-terminating antioxidants have a reactive —NH or —OH functional group and include compounds such as secondary aryl amines or hindered phenols. They function by transfer of hydrogen to free radicals, principally to peroxy radicals. Butylated hydroxytoluene is a widely used example. [Pg.1008]

In Chap. 5, p was defined as the fraction (or probability) of functional groups that had reacted at a certain point in the polymerization. According to the current definition provided by Eq. (6.66), p is the fraction (or probability) of propagation steps among the combined total of propagation and termination steps. The quantity 1 - p is therefore the fraction (or... [Pg.383]

Miscellaneous Curing Reactions. Other functional groups can react with the thiol terminal groups of the polysulfides to cross-link the polymer chains and build molecular weight. For example, aldehydes can form thioacetals and water. Organic and inorganic acids or esters can form thioesters. Active dienes such as diacrylates can add to the thiols (3). Examples of these have been mentioned in the Hterature, but none have achieved... [Pg.456]


See other pages where Terminal functional group is mentioned: [Pg.189]    [Pg.110]    [Pg.196]    [Pg.436]    [Pg.103]    [Pg.143]    [Pg.19]    [Pg.396]    [Pg.201]    [Pg.76]    [Pg.47]    [Pg.36]    [Pg.442]    [Pg.216]    [Pg.47]    [Pg.247]    [Pg.189]    [Pg.110]    [Pg.196]    [Pg.436]    [Pg.103]    [Pg.143]    [Pg.19]    [Pg.396]    [Pg.201]    [Pg.76]    [Pg.47]    [Pg.36]    [Pg.442]    [Pg.216]    [Pg.47]    [Pg.247]    [Pg.539]    [Pg.1014]    [Pg.172]    [Pg.199]    [Pg.217]    [Pg.462]    [Pg.1147]    [Pg.318]    [Pg.346]    [Pg.180]    [Pg.208]    [Pg.209]    [Pg.207]    [Pg.313]    [Pg.240]    [Pg.377]    [Pg.485]    [Pg.199]    [Pg.178]    [Pg.265]    [Pg.440]    [Pg.516]   
See also in sourсe #XX -- [ Pg.148 ]




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Dendrimers functional terminal groups

Dendrimers with terminal functional groups

Functional Groups that Terminate the Core Structure

Metal Centers as Termination Groups (Surface Functionalization)

Oligomers with terminal functional groups

Polymers with Terminal Functional Groups

Siloxane Oligomers with Functional Groups Directly Bonded to the Terminal Silicon Atoms (Si—X)

Terminal functionalization

Terminal groups

Terminal unit/functional group

The Double Functional Group Transformation Terminally Unsaturated

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