Acrylonitrile copolymer with 4-vinylpyridine

Stearamidomethylpyridinium chloride is used in waterproofing textiles. It is made by reacting pyridine hydrochloride with stearamide and formaldehyde. Vmylpyridines are used as components of acrylonitrile copolymers to improve the dyeability of polyacrylonitrile fibers. Tile commercially important products are 2-vinylpyndine 4-vinylpyndine and 2-methyl-5-vinylpyridine. Formulas are shown below. 

Copolymers of 4-Vinylpyridine. Acrylonitrile improves the tensile strength of these reverse-osmosis membranes. Cross-linking qnatemization of the copolymers with diiodobutane improves the performance of the membranes, achieving salt rejection of 95% and hydraulic water permeabihty of up to 30 x 10 cm /(s Pa). The quaternized membranes also are anion exchangeable more than two-thirds of iodide exchanges with chloride (162). 

As indicated in Section 18.4.1, butadiene copolymers had become of interest as potential synthetic rubbers in Germany by about 1929. Attention centred largely on styrene and acrylonitrile copolymers it was also noted that 2-vinylpyridine was a promising comonomer but there were no commercial developments. 2-Vinylpyridine-butadiene-styrene terpolymers were investigated in the U.S.A. in the early 1940 s in connection with the government sponsored synthetic rubber programme. These materials showed some improved properties, but were not of sufficient merit to warrant large-scale production. 

PAN has a solubility parameter of about 11 H and is soluble only in polar solvents, such as dimethylacetamide (DMAc). Because of PAN s high polarity, its fibers are difficult to dye. This difficulty has been overcome by producing copolymers of acrylonitrile with small amounts (4%) of more-hydrophilic monomers, such as jV-vinyl-2-pyrrolidone (left), methacrylic acid (center), or 2-vinylpyridine (right), which have the following structures ... 

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... 

Porous acrylonitrile—DVB copolymer further reacted with diamines or triamines provides a support for Cp 2ZrCl2—MAO catalysts.2 2 pjjg catalyst activity rivals that of silica-supported analogues and no adhesion of polymer to the reactor walls or stirrer was observed. Polypropylene grafted with maleic anhydride allowed to react with MAO acts as a support for a variety of metallocenes. 3 The number of gels in the polymer is lower than when silica is used as the carrier. Porous vinylpyridine—DVB and poly(vinyl chloride) have also been reported as suitable support materials for metallocene catalysts. 

Orion is a highly polymeric fiber resulting from the catalyzed addition copolymerization of acrylonitrile with about 10% vinylpyridine, C7H7N. The vinylpyridine unit is incorporated into the polymer to enable dyes to be adsorbed more readily by the fiber. Normally the copolymer is dissolved in a solvent such as N,N-dimethylacetamide, from which it can be spun into threads. It can also be wet spun from concentrated salt solutions. 

This technique allows the formation of many different types of block copolymers. Lithium metal can be used to initiate polymerizations in solvents of varying polarity. Monomers, like styrene, a-methylstyrene, methyl methacrylate, butyl methacrylate, 2-vinylpyridine, 4 vinylpyridine, acrylonitrile, or methyl acrylate, can be used. The mechanism of initiation depends upon the formation of ion radicals through reactions of lithium with the double bonds ... 

Alternating copolymers are the result of the copolymerization of 2-vinylpyridine with butylvinyl ether in the presence of acetic acid [(a) acetic acid =1 1.3] [610]. Other examples for alternating copolymers are (la)/vinyl acetate copolymerized in the presence of acetic acid [611] and (c)/acrylonitrile as well as (c)/acrylic amide, using K2S2O8 as complexing initiator [612]. 

For PVP, a 150 mV enhancement in y<,c was observed. Lin and coworkers investigated the addition of poly(vinylpyridine-co-acrylonitrile) to an electrolyte containing EC/PC, KI and h. The copolymer was used instead of pure PVP because of the incompatibihty of PVP with electrolytes containing alkali iodides. The authors observed that Voc increased -100 mV, and the efficiency for the quasi-sohd DSSC achieved 6.7%, which is higher than the 6.0% obtained for the initial EC/PC/KFL liquid electrolyte. 

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