Poly /polyaniline copolymer

Polyaniline has been grafted onto the poly(styrenesulfonic acid-co-aminostyrene) backbone using aniline, ammonium persulfate, and hydrochloric acid. The graft copolymer is water soluble and self-doping and can be used in electrical and marine anticorrosive applications. 

FIGURE 9.1. Repeat units of the pyridine-containing polymers and other polymers used in the study (a) poly(p-pyridine) (PPy) (b) poly(/ -pyridyl vinylene) (PPPyV) (c) copolymer of PPY and PPyV [PPyVP(R)2V] (d) wrapped copolymer of pyridylvinylene and penylenevinylene ( PPyVPV) (e) wrapped copolymer of dithienylene and phenylene ( PTP) (f) emeraldine base (EB) form of polyaniline (g) sulfonated polyaniline (SPAN). 

Water can be removed from methanol by a membrane of polyvinyl alcohol cross-linked with polyacrylic acid, with a separation factor of 465.204 A polymeric hydrazone of 2,6-pyridinedialdehyde has been used to dehydrate azeotropes of water with n- and /-propyl alcohol, s- and tort butyl alcohol, and tetrahydrofuran.205 The Clostridium acetobutylicum which is used to produce 1-butanol, is inhibited by it. Pervaporation through a poly(dimethyl-siloxane) membrane filled with cyclodextrins, zeolites, or oleyl alcohol kept the concentration in the broth lower than 1% and removed the inhibition.206 Acetic acid can be dehydrated with separation factors of 807 for poly(4-methyl-l-pentene) grafted with 4-vinylpyridine,207 150 for polyvinyl alcohol cross-linked with glutaraldehyde,208 more than 1300 for a doped polyaniline film (4.1 g/m2h),209 125 for a nylon-polyacrylic acid membrane (5400 g/m2h), and 72 for a polysulfone.210 Pyridine can be dehydrated with a membrane of a copolymer of acrylonitrile and 4-styrenesulfonic acid to give more than 99% pyridine.211 A hydrophobic silicone rubber membrane removes acetone selectively from water. A hydrophilic cross-linked polyvinyl alcohol membrane removes water selectively from acetone. Both are more selective than distillation.212... 

The chain ends of the star polymers can be functionalized. So it is possible to link these sites and form networks or gels of stars. Depending on the chemical nature of the chain end, the crosslinking can be permanent or stimuli-switchable. Patrick-ios et al. [105] have prepared crosslinked double hydrophilic star copolymers made from methacrylic acid (MAA) and poly(ethyleneglycol methacrylate) (PEGMA). Meyer et al. [106] synthesized photocrosslinkable PMAA stars, which could serve as well-defined model polyelectrolyte networks. The polyelectrolyte stars can also be used as template for some nanomaterials. Want et al. [107] prepared strong anionic polyelectrolyte stars by sulfonation of the PS stars. They were used as the template for the preparation of conducting polyaniline. 

The utility of polyaniline in corrosion resistant coatings has been noted [McAndrew et al., 1996]. The addition of polyaniline to acid containing polymers e.g., polyamic acid precursor of poly-imides, styrene-acrylic acid copolymers) allowed for polymeric doping and intermediate corrosion protection of the blends compared to the constituents. Epoxy addition and diisocyante terminated... 

Figure 10.2 Oxidation of molecular hydrogen dissolved in 0.1 M HCIO4 at a stationary gold electrode modified by 0.1 mg cm of platinum dispersed in different electron conducting polymers sweep rate = 5 mV s T = 25°C (—) polyaniline (---) polypyrrole (—) poly(3-methylthiophcnc) (...) pyrrole-dithiopene copolymer, (Reprinted with permission from ref 133)...

Figure 2.13 Schematic illustration of the process of fabricating a porous PANI-NF film by a galvanostatic method using porous poly(styrene-block-2-vinylpyridine) diblock copolymer films as templates. (Reprinted with permission from Langmuir, One-Step Route to the Fabrication of Highly Porous Polyaniline Nanofiber Films by Using PS-b-PVP Diblock Copolymers as Templates by X. Li, S. Tian, Y. Ping et ai, 2 , 2 , 9393-9397. Copyright (2005) American Chemical Society)...

Conductive polyaniline (PANI) formed the core of the five-component continuous system that also included high-density polyethylene (HOPE), polystyrene (PS), poly(methyl methacrylate) (PMMA), and poly(vinylidene fluoride) (PVDF) along with PS-co-PMMA copolymer. Figure 1.10 shows the SEM micrographs of PANI network in PS/PMMA/PVDF/PANI and PS/PS-co-PMMA/PMMA/PVDF/PANI blends after extraction of all phases by DMF followed by freeze drying. 

Polyaniline has also been blended with pluronic acids—poly(ethylene oxide)—poly(propylene oxide)— poly(ethylene oxide) triblock copolymers [27], which have been used in a range of medical and pharmaceutical products. As with all composite materials containing two discrete phases, the issue of phase segregation over time needs to be considered. 

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