Poly polystyrene block copolymer

Block copolymers were synthesized by a combination of fipase-catalyzed polymerization and atom transfer radical polymerization (ATRE). " " At first, the polymerization of 10-hydroxydecanoic acid was carried out by using lipase CA as catalyst. The terminal hydroxy group was modified by the reaction with a-bromopropionyl bromide, followed by ATRP of styrene using CuCE2,2 -bipyridine as catalyst system to give the polyester-polystyrene block copolymer. Trichloromethyl-terminated poly(e-CL), which was synthesized by lipase CA-catalyzed polymerization with 2,2,2-trichloroethanol initiator, was used as initiator for ATRP of styrene. 

Nakayama Y., Miyamura M., Hirano Y., Goto K., Matsuda T., Preparation of poly(ethylene glycol)-polystyrene block copolymers using photochemistry of dithiocarbamate as a reduced cell-adhesive coating material, Biomaterials 1999 20 963-970. 

Poly(styrene)-poly(lsoprene) and polystyrene-poly(butadiene) block copolymers... 

A block copolymer 55 consisting of a polystyrene block and a poly (CL) block was found to be an effective blending agent for the combination between polystyrene and poly(vinyl chloride). A po ybutadiene/poly(CL) block copolymer was an efficient blending agent for a mixture of polybutadiene and polyacrylonitrile. In addition, a block copolymer of poly(hydrogenated 1,4-butadiene) with poly(CL) allows a three-component mixture of polystyrene, polyethylene and poly(vinyl chloride) to be blended. 

In this system using a polystyrene containing block copolymer, the polystyrene segment should readily partition into the lipophilic polystyrene particle core while the poly(FOA) or PDMS block is solubilized in the CO2 continuous phase to provide steric stabilization and prevent coagulation. In comparison of the polystyrene-b-poly(FOA) diblock copolymers to the polystyrene-b-PDMS diblock copolymers, it was found that the use of a polystyrene-b-PDMS stabilizer gives much more monodisperse particles. This most likely arises from the synthetic technique employed in the surfactant synthesis. The blocks in the polystyrene-b-PDMS block copolymers have a much narrower polydispersity than the blocks in the polystyrene-b-poly(FOA) block copolymers. It was noted that the particles obtained in... 

The use of core-shell impact modifiers combined with styrene-hydrogenated poly butadiene block copolymers in sPS is described by Rohm and Haas [24]. The core of the former type is of polybutadiene or its copolymer, the shell consists predominately of polystyrene. Rohm and Haas found that a synergistic effect is present and that the Izod notched impact strength is higher when both rubber types are used instead of only one. 

Starting Material. 1,2-polybutadiene (PB) and the A-polystyrene-B-1,2-poly-butadiene block copolymer (PSPB) were obtained by "living 1 anionic polymerisation under high-vacuum conditions at -78°C with sec-buthyllithium as initiator. 

Tphe surface activity of block copolymers containing dimethylsiloxane units as one component has received considerable attention. Silicone-poly ether block copolymers (1,2,3) have found commercial application, especially as surfactants in polyurethane foam manufacture. Silicone-polycarbonate (4, 5), -polystyrene (6, 7), -polyamide (8), -polymethyl methacrylate (9), and -polyphenylene ether (10) block copolymers all have surface-modifying effects, especially as additives in other polymeric systems. The behavior of several dimethylsiloxane-bisphenol A carbonate block copolymers spread at the air—water interface was described in a previous report from this laboratory (11). Noll et al. (12) have described the characteristics of spread films of some polyether—siloxane block co-... 

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. 

G. Dorff, M. Hahn, A. Laschewsky, A. Lieske, Optimization of the propoty profile of poly-L-ladide by synthesis of PLLA-polystyrene-block copolymers. J. Appl. Polym. Sci. 127 (2013) 120-126, doi 10.1002/app.37836. 

E. Kaul, V. Senkovskyy, R. Tkachov, V. Bocharova, H. Komber, M. Stamm, A. Kiriy, Synthesis of a Bifunctional Initiator for Controlled Kumada Catalyst- Transfer Polycondensation/Nitroxide-Mediated Polymerization and Preparation of Poly(3-Hexylthiophene)-Polystyrene Block Copolymer Therefrom. Macromolecules 2010,43,77-81. 

We use poly sty rene-f>-poly butadiene block copolymers as the starting material with preformed polymer architecture. These polymers are comparatively cheap and easily accessible. For the present problems a series of narrowly distributed polystyrene-Zr-polybutadiene block copolymers with rather different molecular weights were synthesized via anionic polymerization (Figure 10.4, Table 10.1). As a test for the modification of technological products, a commercial triblock copolymer was also used. 

Schmidt-Naake, G. and Butz, S. 1996. Living free radical donor-acceptor copolymerization of styrene and N-cyclohexyl maleimide and the synthesis of poly[styrene-co-(N-chlohexylmaleimide)]/polystyrene block copolymers. Macrgmoleadat a i ... 

Figure 8.8 The idealized structure of the polystyrene-Z /ocA -polybutadiene-Z /(9cA -poly-styrene block copolymer m and m2 denote the number of monomers in the styrene block and n denotes the number of monomers in the butadiene block.

Problem 11.16 A dual initiator, 4-hydroxy-butyl-2-bromoisobutyiate (HBBIB) was synthesized (Bernaerts et al., 2003) by the reaction of 1,4-butanediol with 2-bromoisobutyric acid using p-toluene sulfonic acid as catalyst in toluene. Suggest a scheme for the synthesis of well-de ned poly(tetrahydrofuran)-f>-polystyrene block copolymer with controlled molecular weights and low polydispersities using HBBIB. 

Electrical properties have been reported on numerous carbon fiber-reinforced polymers, including carbon nanoflber-modified thermotropic liquid crystalline polymers [53], low-density polyethylene [54], ethylene vinyl acetate [55], wire coating varnishes [56], polydimethyl siloxane polypyrrole composites [50], polyacrylonitrile [59], polycarbonate [58], polyacrylonitrile-polycarbonate composites [58], modified chrome polymers [59], lithium trifluoromethane sulfonamide-doped polystyrene-block copolymer [60], boron-containing polyvinyl alcohols [71], lanthanum tetrafluoride complexed ethylene oxide [151, 72, 73], polycarbonate-acrylonitrile diene [44], polyethylene deoxythiophe-nel, blends of polystyrene sulfonate, polyvinyl chloride and polyethylene oxide [43], poly-pyrrole [61], polypyrrole-polypropylene-montmorillonite composites [62], polydimethyl siloxane-polypyrrole composites [63], polyaniline [46], epoxy resin-polyaniline dodecyl benzene sulfonic acid blends [64], and polyaniline-polyamide 6 composites [49]. 

Since poly(methyl methacrylate) radicals terminate by disproportionation, the polysiloxane-polyMMA block copolymers may not have the multiblock structures the polysiloxane-polystyrene block copolymers have. Instead they might be expected to have BAB triblock or AB diblock structures. In accord with this expectation, the poly-siloxane-polyMMA blocks prepared (Table III) have narrow molecular weight distributions, Mw/Mn 2, and monomodal GPC curves. 

Initial intrinsic viscosity (dl/gm) Free poly(methyl acrylate) Free polystyrene Block copolymer... 

Girod M, Mazarin M, Phan TNT, Gigmes D, Charles L. Determination of block size in poly(ethylene oxide)-b-polystyrene block copolymers by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. J Polym Sci A Polym Chem 2009 47 3380-3390. 

Prud homme J, Bywater S. Light-scattering studies on polystyrene-poly isoprene block copolymers. Macromolecules 1971 4 543-548. 

Sauer BB, Yu H, Tien CF, Hager DF (1987) A surface light scattering study of a poly (ethylene oxide)-polystyrene block copolymer at the air-water and heptane-water interfaces. Macromolecules 20 393 00... 

The topology of this product with a bulk hydrophobic structure inside and a hydrophilic part outside makes it particularly attractive for applications such as unimo-lecular micelles. On using the same procedure, norbor-nyl-poly(ethylene oxide)-polystyrene macromonomer was polymerized to polynorbornene-poly(ethylene oxide)-polystyrene block copolymer (121) [Eq. (53)]. 

Another route toward potentially amphiphilic copolymers is the copolymerization of styrene with maleic anhydride, which has the particularity to lead to poly(styrene-co-maleic anhydride) alternate copolymers and ultimately to poly (styrene-co-maleic anhydtide)-b-polystyrene block copolymers after complete depletion in maleic anhydride. Maleimide comonomers were similarly copolymetized with styrene such... 

Several studies have concerned the microstnicture of lamellae in materials such as the block copolymers polystyrene-h/oc/r-poly-l-vinylpyridine [139] and polystyrene-h/oc/r-polybutadiene [140], as well as single crystals of poly-para-xylylene [139], and reveal features (such as intersecting lamellae (figure Bl.19.29)) that had not been previously observed. 

Gun Propellents. Low sensitivity gun propeUants, often referred to as LOVA (low vulnerabUity ammunition), use RDX or HMX as the principal energy components, and desensitizing binders such as ceUulose acetate butyrate or thermoplastic elastomers (TPE) including poly acetal—polyurethane block copolymers, polystyrene—polyacrjiate copolymers, and glycidyl azide polymers (GAP) to provide the required mechanical... 

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