Polystyrene-block-polyisobutylene

FIGURE 7.6 Reproducibility of the synthesis of dendritic polyisobutylene capped with polystyrene blocks (SDIBS) on a pound scale. The various symbols represent different experiments (details will be published elsewhere). 

FIGURE 7.9 Architecture of dendritic polyisobutylene capped with polystyrene blocks (SDIBS). 

Characteristic Data of Selected Dendritic Polyisobutylene Capped with Polystyrene Blocks (SDIBS)-Hydroxide (OH) Samples... 

St. Lawrence, S., Shinozaki, D.M., Puskas, J.E., Gerchcovich, M., and Myler, U. Micro-mechanical testing of polyisobutylene-polystyrene block-type thermoplastic elastomers. Rubber Chem. TechnoL, 74, 601-613, 2001. 

Puskas, J.E., Pattern, W.E., Wetmore, P.M., and Krukonis, A. Synthesis and characterization of novel six-arm star polyisobutylene-polystyrene block copolymers. Rubber Chem. TechnoL, 72, 559-568, 1999. Puskas, J.E., Wetmore, P.M., and Krukonis, A. Supercritical fluid fractionation of polyisobutylene-polystyrene block copolymers, Polym. Prepr., 40, 1037-1038, 1999. 

Kwon, Y., Antony, P., Paulo, C., and Puskas, J.E. Arborescent polyisobutylene-polystyrene block copolymers—a new class of thermoplastic elastomers, Polym. Prepr., 43, 266-267, 2002. 

Treatment of polyisobutylene (which contains terminal double bonds) with ozone followed by thermolysis produces polymeric radicals. Isobutylene-styrene block copolymer is formed when thermolysis is performed in the presence of styrene, but the process is not efficient because polystyrene and polyisobutylene homopolymers constitute more than half of the product [Cunliffe et al., 2001]. 

QU2 Quintana, J.R., Salazar, R.A, and Katime, I., Micelle formation and polyisobutylene solubilization by polystyrene-Z>/oc -poly(ethylene-co-butylene)-Z>/ocA -polystyrene block copolymers, Macrowo/. Chem. Phys., 196, 1625, 1995. 

The discovery of living cationic polymerization has provided methods and technology for the synthesis of useful block copolymers, especially those based on elastomeric polyisobutylene (Kennedy and Puskas, 2004). It is noteworthy that isobutylene can only be polymerized by a cationic mechanism. One of the most useful thermoplastic elastomers prepared by cationic polymerization is the polystyrene-f -polyisobutylene-(>-polystyrene (SIBS) triblock copolymer. This polymer imbibed with anti-inflammatory dmgs was one of the first polymers used to coat metal stents as a treatment for blocked arteries (Sipos et al., 2005). The SIBS polymers possess an oxidatively stable, elastomeric polyisobutylene center block and exhibit the critical enabling properties for this application including processing, vascular compatibility, and biostability (Faust, 2012). As illustrated below, SIBS polymers can be prepared by sequential monomer addition using a difunctional initiator with titanium tetrachloride in a mixed solvent (methylene chloride/methylcyclohexane) at low temperature (-70 to -90°C) in the presence of a proton trap (2,6-dt-f-butylpyridine). To prevent formation of coupled products formed by intermolecular alkylation, the polymerization is terminated prior to complete consumption of styrene. These SIBS polymers exhibit tensile properties essentially the same as those of... 

The chemical modification of homopolymers such as polyvinylchloride, polyethylene, poly(chloroalkylene sulfides), polysulfones,poly-chloromethylstyrene, polyisobutylene, polysodium acrylate, polyvinyl alcohol, polyvinyl chloroformate, sulfonated polystyrene block and graft copolymers such as poly(styrene-block-ethylene-co-butylene-block-styrene), poly(1,4-polybutadiene-block ethylene oxide), star chlorine-telechelic polyisobutylene, poly(lsobutylene-co-2,3-dimethy1-1,3-butadiene), poly(styrene-co-N-butylmethacrylate) cellulose, dex-tran and inulin, is described. 

Kwon Y, Antony P, Paulo C and Puskas J E (2002) Arborescent polyisobutylene-polystyrene block copolymers - A new class of thermoplastic elastomers, Polym Prepr ACS 43 266-267. 

D.) Synthesis of Polyisobutylene and Polystyrene block copolymer with dltolylethylene. 

Puskas J.E., Antony P., ElFray M., and Altstadt V. The effect of hard and soft segment composition and molecular architecture on the morphology and mechanical properties of polystyrene-polyisobutylene thermoplastic elastomeric block copolymers, Eur. Polym. J., 39, 2041, 2003. 

Puskas, J.E. Biomacromolecular engineering Design, S3mthesis and characterization. One-pot synthesis of block copolymers of arborescent polyisobutylene and polystyrene, Polym. Adv. TechnoL, 7, 1, 2006. 

Antony, P., Kwon, Y., Fhiskas, J.E., Kovar, M., and Norton, P.R. Atomic force microscopic studies of polystyrene-polyisobutylene block copolymers, Eur. Polym, J., 40, 149-157, 2003. 

HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HNS NTO NTO/HMX NTO/HMX NTO/HMX PETN PETN PETN PETN PETN PETN PETN PETN PETN PETN RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX TATB/HMX Cariflex (thermoplastic elastomer) Hydroxy-terminated polybutadiene (polyurethane) Hydroxy-terminated polyester Kraton (block copolymer of styrene and ethylene-butylene) Nylon (polyamide) Polyester resin-styrene Polyethylene Polyurethane Poly(vinyl) alcohol Poly(vinyl) butyral resin Teflon (polytetrafluoroethylene) Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Cariflex (block copolymer of butadiene-styrene) Cariflex (block copolymer of butadiene-styrene) Estane (polyester polyurethane copolymer) Hytemp (thermoplastic elastomer) Butyl rubber with acetyl tributylcitrate Epoxy resin-diethylenetriamine Kraton (block copolymer of styrene and ethylene-butylene) Latex with bis-(2-ethylhexyl adipate) Nylon (polyamide) Polyester and styrene copolymer Poly(ethyl acrylate) with dibutyl phthalate Silicone rubber Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Epoxy ether Exon (polychlorotrifluoroethylene/vinylidine chloride) Hydroxy-terminated polybutadiene (polyurethane) Kel-F (polychlorotrifluoroethylene) Nylon (polyamide) Nylon and aluminium Nitro-fluoroalkyl epoxides Polyacrylate and paraffin Polyamide resin Polyisobutylene/Teflon (polytetrafluoroethylene) Polyester Polystyrene Teflon (polytetrafluoroethylene) Kraton (block copolymer of styrene and ethylene-butylene)... 

Other multifunctional initiators include star polymers prepared from initiators via living radical or other living polymerizations. In particular, all of the star polymers via metal-catalyzed living polymerization, by definition, carry a halogen initiating site at the end of each arm, and thus they are potentially all initiators. Thus, star-block copolymers with three polyisobutylene-Mock-PMMA arms and four poly-(THF) -A/oc/F polystyrene or poly(THF)-Woc/c-polysty-rene-Wock-PMMA were synthesized via combination of living cationic and copper-catalyzed living radical polymerizations.381,388 Anionically synthesized star polymers of e-caprolactone and ethylene oxide have... 

Recently, block copolymers micelles filled with MoS nanoparticles (well miscible with mineral oil) were synthesized in heptane using interaction of Mo(CO)e with polystyrene-fc/ock-polybutadiene (PS-fc-PB) and polystyrene-i /ock-polyisobutylene (PS-fc-PIB) followed by H2S treatment [39]. To position MoS c nanoparticles in the PS core, the reaction between Mo(CO)e and block copolymer should be carried out in argon atmosphere. This yields arene Mo tricarbonyl complexes while olefin Mo carbonyl complexes do not form. By contrast, to place MoS nanoparticles in the PB corona, complexation with Mo(CO)e should be carried out in the CO atmosphere. This suppresses forma-... 

The direct coupling of preformed living blocks (usually cation and anion or group transfer) also enables the formation of block copolymers, such as polytetrahydrofuran-b-polystyrene-b-polytetrahydrofuran [13], polystyrene-b-polytetrahydrofuran [14], polystyrene-b-poly(ethyl vinyl ether) [15], poly(methyl methacrylate)-b-polytetrahydrofuran [16], poly[0-(jS-D- glucopyranosyl)-L-serine]-b-poly(2-methyl-2-oxazoline) [8], poly(methyl methacrylate)-b-poly(butyl vinyl ether) [17], polyisobutylene-b-poly(vinyl ferrocene), and poly(vinyl ferrocene)-polyisobutylene-b-poly(vinyl ferrocene) [18]. A typical example of such a coupling process between oppositely charged macroions is presented in Scheme 11.1, for the preparation of polystyrene-b-poly(ethyl vinyl ether) [15]. 

In a more recent study [88], the chlorine end groups of PIB were quantitatively converted to bromoester groups to facilitate ATRP from end-positioned activated ester groups (Scheme 11.21). In this way, the capping with short blocks of PSt observed in the earlier method could be avoided. The concept was further extended to the preparation of PIB-h-PMMA diblock [89], poly(t-butyl acrylate)-b-polyisobutylene-b-polystyrene triblock [90], and amphiphilic pentablock copolymers based on PIB [91]. 

The partial molar quantities of mixing were determined for normal and branched alkanes (O5 — Cio), cyclohexane, benzene and tetrachloromethane in polyisobutylene [57]. Partial molar enthalpies of mixing were measured for normal alkenes in low and high density polyethylene, polypropylene, polybutene-1, polystyrene, poly(methyl acrylate), poly(vinyl chloride), polyCN-isopropyl-acrylamide), ethylene-vinyl acetate copolymer, ethylene-carbon oxide copolymer [88] normal, branched and cyclic alkanes, benzene, n-butylbenzene, ois- and ra s-decalin, tetraline and naphthalene in polystyrene at 183, 193 and 203°C [60] these solutes in poly (methyl acrylate) [57] n-nonane, n-dodecane and benzene in polystyrene in the range 104.8 — 165.1 C [71] O7—C, C12 normal alkanes and aromatic hydrocarbons in polystyrene at an average temperature of 204.9°C [72], C7—Cg normal alkanes in poly(ethylene oxide) at an average temperature of 66.5 "C [72] normal alkanes in ethylene oxide—propylene oxide block copolymers (Pluronics L 72, L 64 and F 68) at the same average temperature [72]. 

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