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Telechelic polyisobutylenes

In one of their notable examples, the hydroboration polymerization of low molecular weight allyl-telechelic polyisobutylene with tripylborane (trip = 2,4,6-triisopropylphenyl) was found to yield air-stable organoboron segmented block copolymers. These boron main-chain polymers (8) (Fig. 8), unlike the general ones, were stable to air. The stability was due to the steric hindrance of the bulky tripyl groups preventing oxygen attack of the borons.28... [Pg.26]

Figure 8 The air-stable 77-conjugated organoboron segmented block copolymer (8) obtained by the hydroboration polymerization of allyl-telechelic polyisobutylene, 1,9-decadiene, and tripylborane. (Adapted from ref. 28.)... Figure 8 The air-stable 77-conjugated organoboron segmented block copolymer (8) obtained by the hydroboration polymerization of allyl-telechelic polyisobutylene, 1,9-decadiene, and tripylborane. (Adapted from ref. 28.)...
Table I. Comparison of Semicontinuous and Conventional Polymerization Techniques for the Preparation of Telechelic Polyisobutylenes by Binifer and Trinifer... Table I. Comparison of Semicontinuous and Conventional Polymerization Techniques for the Preparation of Telechelic Polyisobutylenes by Binifer and Trinifer...
E. Walch and R. Gaymans, Telechelic polyisobutylene with unsaturated end groups and with anhydride end groups, Polymer, 35(8) 1774-1778, April 1994. [Pg.182]

J. Feldthusen, B. Iv n, A.H.E. Muller, and J. Kops, Synthesis of linear and three-arm star tert-chlorine-telechelic polyisobutylenes by a two-step conventional laboratory process, Macromol. Rapid Commun., 18(5) 417-425,1997. [Pg.182]

Figure 1. Linear and three-arm star telechelic polyisobutylene-based metal sulfonate ionomers. Figure 1. Linear and three-arm star telechelic polyisobutylene-based metal sulfonate ionomers.
Figure 2. Stress vs. strain for telechelic polyisobutylene-based metal sulfonate ionomers. Numbers at each curve indicate sample molecular weight and mole % ion content (in parenthesis). Figure 2. Stress vs. strain for telechelic polyisobutylene-based metal sulfonate ionomers. Numbers at each curve indicate sample molecular weight and mole % ion content (in parenthesis).
An interesting group of new ionomers have been prepared from liquid olefin telechelic polyisobutylenes. Syntheses involved the quantitative sulfonation (by acetyl sulfate) of linear and/or tri-arm star polyisobutylenes carrying exactly two or three -CH2-C(CH3)=CH2 termini, respectively, followed by neutralization with various bases ... [Pg.11]

Quantitative epoxidation of olefin-telechelic polyisobutylenes yielded interesting new epoxy-telechelic products. Isomerization of the linear epoxy-telechelic polyisobutylene quantitatively yielded aldehyde-telechelic chains ... [Pg.11]

Telechelic polyisobutylene sulfonate Ionomers Model ionomer... [Pg.9]

Fundamental studies directed toward the elucidation of the mechanism of olefin i.e.f isobutylene, polymerizations yielded a new method for the synthesis of novel linear and tri-arm star telechelic polymers and oligomers [1,2]. The synthesis involves the use of bi- or tri-functional initiator/transfer agents, so called inifers (binifers and trinifers), in conjunction with BCI3 coinitiator and isobutylene, and gives rise to polyisobutylenes carrying exactly two or three terminal -CH2-C(CH3)2Cl groups. These liquid telechelic polyisobutylene chlorides can be readily and quantitatively converted to telechelic polyisobutylene di- or tri-olefins [2,3] which in turn can quantitatively yield by hydroboration/oxidation telechelic polyisobutylene di- and triols [4,5]. [Pg.383]

This paper concerns the synthesis of a new telechelic polyisobutylene diol, a, a)-di (hydroxy) po lyi so-butylene (formula IV in Scheme I), and the preparation of new linear polyurethanes containing polyisobutylene (PIB) soft segments by the use of this diol and conv-ventional extension techniques with TDI. [Pg.383]

A. Synthesis of Linear Telechelic Polyisobutylene Diols. According to model calculations [5-7] efficient chain extension of telechelics can be carried out only with prepolymers having (number average... [Pg.385]

The functionality of the obtained telechelic polyisobutylenes is affected mainly by the intramolecular cycloalkylation of the initiator. [Pg.118]

Cycloindane formation can be avoided by working under proper temperature and solvent mixture conditions (169, 170). By using tricumyl chloride-BCl trinifer system, three-arm star telechelic polyisobutylenes carrying exactly three -C(CH2)3C1 end groups have been synthesized by Kennedy et al. (171. 172). [Pg.118]

Poly(a-raethy1styrene- -isobutylene- -a-methyIstyrene) was prepared by the initiation of a-raethylstyrene polymerization from a ditelechelic polyisobutylene containing tert-chlorine end groups. AlEt2Cl was used as coinitiator (177). Poly(isobutylene- -styrene) and poly(isobutylene- -a-raethylstyrene) were prepared by the initiation of styrene and a-raethyIstyrene polymerization from an asymmetric telechelic polyisobutylene, that is, (CH2)2-C=Ch-CH PiB—CH2-C(CH3)2C1 and AlEt2Cl (178). [Pg.119]

The same chemistry was used for the three-arm star telechelic polyisobutylene synthesis (171). These two functional groups (that is, propenyl and hydroxyl) afford the possibility of almost any kind of functional groups to be introduced at the chain ends of polyisobutylene. By derivation of hydroxyl and propenyl terminated polyisobutylene, telechelics containing carboxylic (191. 192), -SiCl and H-SiH (193. 19A). acryloyl and methacryloyl (195). [Pg.120]

Synthesis and Characterization of a-Hydroxyl-a>-Methoxycarhonyl and oc-Hydroxyl (D>Carhoxyl Asynunetric Telechelic Polyisobutylenes... [Pg.135]

GR1 Gregg, C.J., Stein, P.S., and Radosz, M., Phase behavior of telechelic polyisobutylene (PIB) in subcritical and supercritical fluids I., Macromolecules, 27, 4972, 1994. [Pg.547]

Diydroxy telechelic polyisobutylene (OH-PIB-OH), which is of great importance for the preparation of fimctionalized polymers and polymer networks, was characterized by MALDI-TOF using a DITH/CF3COOAg matrix system. Despite the apolar nature of FIB, tire good quality MALDl spectra can be explained by the fact that PIB chains have two hydroxyl end-groups. This permits the formation of stable [HO-PIB-OH -i-Ag] ions. A good agreement was also foxmd between the calculated isotope distributions and the distributions determined by means of MALDI. ... [Pg.481]

Keki, S., Deak, G., Mayer-Posner, E. J., and Zsuga, M., MALDI-TOF MS Characterization of Dihydroxy Telechelic Polyisobutylene, Macromol. Rapid Commun., 21, 770, 2000. [Pg.524]

E. N. Peters, Telechelic polyisobutylene and block copolymer derivatives, U.S. Patent... [Pg.380]

Quenching of living carbocationic polymerization also leads to tert-chlorine-telechelic polyisobutylenes (222). Synthesis of mono- (223-226), di- (227-235), tri- (236), and tetrafianctional (237) polyisobutylenes carrying Cl termini was reported. [Pg.8214]


See other pages where Telechelic polyisobutylenes is mentioned: [Pg.204]    [Pg.923]    [Pg.125]    [Pg.440]    [Pg.385]    [Pg.385]    [Pg.388]    [Pg.389]    [Pg.120]    [Pg.136]    [Pg.440]    [Pg.11]    [Pg.225]   


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Polyisobutylenes

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Telechelics

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