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  • 2-sulfoethyl methacrylate  (1)
  • common ion salt  (1)
  • extractables  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Amphiphilic networks. VII. Synthesis and characterization of pH-sensitive poly(sulfoethyl methacrylate)-1-polyisobutylene networksFor Part VI of this series, see REFERENCE 22. (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 32 (1994), S. 3153-3160 
    Details
    ISSN: 0887-624X
    Keywords: polyisobutylene ; 2-sulfoethyl methacrylate ; copolymer ; network ; synthesis ; characterization ; swelling ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of environmentally sensitive amphiphilic networks consisting of 2-sulfoethyl methacrylate (SEMA) chains linked by methacrylate-ditelechelic polyisobutylene (MA-PIB-MA) chains have been prepared and characterized. Network composition was determined after sequential solvent extraction by elemental analysis. These networks are two-phase microheterogeneous systems containing hydrophobic rubbery PIB domains (Tg ∼ -60°C) and hydrophilic poly(2-sulfoethyl methacrylate) domains (Tg ∼ -15°C). They exhibit large contact-angle hysteresis in water which is due to surface segmental mobility and microheterogeneity. By increasing the SEMA content of the networks the contact-angle hysteresis increases. This phenomenon is due to an increase in the advancing contact angle most likely caused by the migration of the nonpolar PIB domains toward the surface and concomitant decrease of the receding contact angle. These amphiphilic networks exhibit non-Fickian swelling in n-heptane, as well as in water, and show pH-sensitive swelling in aqueous media. They rapidly and reversibly swell and deswell in response to increasing or decreasing the pH of the media (cycling between pH = 2 and 12). © 1994 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1994.080321616
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  • 2
    Electronic Resource
    Electronic Resource
    Novel polyisobutylene/poly(dimethylsiloxane) bicomponent networks. I. Synthesis and characterization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1891-1899 
    Details
    ISSN: 0887-624X
    Keywords: polyisobutylene ; poly(dimethylsiloxane) ; hydrosilation ; bicomponent networks ; molecular weight between crosslinks ; network functionality ; sol fraction ; extractables ; model networks ; end-linking ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of novel polyisobutylene (PIB)/poly(dimethylsiloxane) (PDMS) bicomponent networks is described. The synthesis strategy (see Figure 1) was to prepare well-defined and -characterized allyl-tritelechelic polyisobutylenes [φ(PIB - C - C=C)3] and SiH-ditelechelic poly(dimethylsiloxanes) (HSi-PDMS-SiH) and then crosslink these moieties by hydrosilation. The φ(PIB - C - C=C)3 was prepared by living isobutylene polymerization followed by end-quenching with allyltrimethylsilane, whereas the HSi-PDMS-SiH was obtained by equilibrium polymerization of octamethylcyclotetrasiloxane and tetramethyldisiloxane. The detailed structures of the starting polymers were characterized by GPC and 1H-NMR spectroscopy. A series of PIB/PDMS bicomponent networks of varying compositions and average molecular weights between crosslinks (Mc) of ∼ 20,000 g/mol were assembled. Optimum crosslinking conditions were defined in terms of H2PtCl6 catalyst concentration, nature of solvent, time, temperature, and stoichiometry of ∼ CH2CH=CH2/∼SiH groups, allowing for the convenient synthesis of well-defined model bicomponent networks. Swelling studies and elemental analysis confirm the correctness of the synthetic strategy. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1891-1899, 1998
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Living carbocationic polymerization of isobutyl vinyl ether and the synthesis of poly[isobutylene-b-(isobutyl vinyl ether)] (1993)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 31 (1993), S. 2825-2834 
    Details
    ISSN: 0887-624X
    Keywords: carbocationic polymerization ; living polymerization ; poly(isobutyl vinyl ether) ; polyisobutylene ; block copolymers ; titanium tetrachloride ; common ion salt ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The MeCH(O-i-Bu)Cl/TiCl4/MeCONMe2 initiating system was found to induce the rapid living carbocationic polymerization (LC⊕Pzn) of isobutyl vinyl ether (IBuVE) at -100°C. Degradation by dealcoholation which usually accompanies the polymerization of alkyl vinyl ethers by strong Lewis acids is “frozen out” at this low temperature and poly(isobutyl vinyl ether)s (PIBuVEs) with theoretical molecular weights up to ca. 40,000 g/mol (calculated from the initiator/monomer input) and narrow molecular weight distributions (M̄w/M̄n ≤ 1.2) are readily obtained. According to 13C-NMR spectroscopy, PIBuVEs prepared by living polymerization at -100°C are not stereoregular. The MeCH(O-i-Bu)Cl/TiCl4 combination induces the rapid LC⊕Pzn of IBuVE even in the absence of N,N-dimethylacetamide (DMA). The addition of the common ion salt, n-Bu4NCl to the latter system retards the polymerization and meaningful kinetic information can be obtained. The kinetic findings have been explained in terms of TiCl4. IBuVE and TiCl4 · IBuVE and TiCl4 · PIBuVE complexes. The HCl (formal initiator)/TiCl4/DMA combination is the first initiating system that can be regarded to induce the LC⊕Pzn of both isobutylene (IB) and IBuVE. Polyisobutylene (PIB)-PIBuVE diblocks were prepared by sequential monomer addition in “one pot” by the 2-chloro-2,4,4-trimethylpentane (TMP-Cl)/TiCl4/DMA initiating system. Crossover efficiencies are, however, below 35% because the PIB⊕ + IBuVE → PIB-b-PIBuVE⊕ crossover is slow. © 1993 John Wiley & Sons, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1993.080311120
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