Polyacrylonitrile copolymers

A recently developed class of compounds called Super Slurpers based on starch- polyacrylonitrile copolymers are able to absorb as much as 500 to 1000 times their weight of water, depending on the purity of the water (19, 20, 21). The formation of these copolymers is catalyzed by Ce ion. These polymers were developed by the U.S, Department of Agriculture and have potential agricultural uses as water storage additives as well as obvious consumer and industrial applications. 

Coleman, M. M., Sivy, G. T. Fourier Transform Infrared Studies of the Degration of Polyacrylonitrile) Copolymers I. Introduction and Comparative Rates of the Degradation of Three Copolymers Below 200 °C and Under Reduced Pressure. Preprint submitted to CARBON... 

Table I. Solubility of Cellulose in Polyacrylonitrile Copolymers of Cellulose in Cupriethylenediamine (0.5M) at 25°C...

Table II. Infrared Spectral Data of Polyacrylonitrile Copolymers of Cellulose...

Table III. Copolymer Density of Polyacrylonitrile Copolymers of Cellulose Breaking Strength Density, Polyacrylonitrile, of Fibrous Copolymer, grams/ml % X 10 gram ...

Most of today s ultrafiltration membranes are made by variations of the Loeb-Sourirajan process. A limited number of materials are used, primarily polyacrylonitrile, poly(vinyl chloride)-polyacrylonitrile copolymers, polysulfone, poly(ether sulfone), poly(vinylidene fluoride), some aromatic polyamides, and cellulose acetate. In general, the more hydrophilic membranes are more fouling-resistant than the completely hydrophobic materials. For this reason water-soluble... 

In hemodialysis, blood from the patient flows on one side of a membrane and a specially prepared dialysis solution is fed to the other side. Waste material in the blood such as urea, excess acids, and electrolytes diffuse into the dialysate the blood is then returned to the patient, as shown in Fig. 48. A patient typically undergoes dialysis three times per week in sessions lasting several hours each. Modern dialysis systems combine sophisticated monitoring and control functions to ensure safe operation. Regenerated cellulose was the first material used in hemodialysis membranes because of its biocompatibility and low cost it remains the most popular choice. Subsequently, high-permeability dialysis membranes derived from cellulose esters, modified polysulfone, or polyacrylonitrile copolymers have also gained wide acceptance because of the shorter sessions they make possible. 

Hydrolysis of Bamboo-Polyacrylonitrile Copolymer. In order to isolate the polymer branches of the graft copolymers and to check the accuracy of the grafting percentages... 

Nevertheless, the migration of water into the fiber is sufficient to produce the above-mentioned plasticization effect. The chain mobility is inaeased, as indicated by a decrease of the glass transition temperature by 35—50 C This is a very fortunate fact, because dyeing of the fibers is possible only above the Tg, where the increased polymer segment mobility permits dye diffusion within the fiber. For the commercial polyacrylonitrile copolymer fibers, the Tg in water hes in the r on of= 80 so that dyeing at, or slightly below, the boiling point of water becomes... 

Link et al. (35) proposed the use of tantalum and tungsten to add radiopacity to hydrogel embolic agents for embolotherapy and studied the emboli formed by coagulation under high pressure of a 1 1 or 2 1 mixture of tungsten particles (1-10 jam) and a liquid hydrogel (polyacrylonitrile copolymer) in a rabbit model. 

A membrane designated "Solrox" made by Sumitomo Chemical Company is closely related to the above plasma polymerized composite membranes. A 1980 report by T. Sano described the Sumitomo process (31). A support film was cast from a polyacrylonitrile copolymer containing at least 40 mole percent acrylonitrile. The support film was dried and exposed to a helium or hydrogen plasma to form a tight cross-linked surface skin on the porous polyacrylonitrile support film. Data in a U.S. Patent issued in 1979 to Sano et al showed that the unmodified support film had a water flux of 87 gfd (145 L/ sq m/hr) at 142 psi (10 kg/sq cm). After the plasma treatment a reverse osmosis test using 0.55 percent NaCl at 710 psi (4895 kPa) showed 10.5 gfd (17.5 L/sq m/hr) flux at 98.3 percent salt rejection (32). This membrane appears to fall between a conventional asymmetric membrane and a composite membrane. If the surface skin is only cross-linked, one might call it a modified asymmetric membrane. However, if the surface skin is substantially modified chemically to make it distinct from the bulk of the membrane it could be considered as a composite type. 

McGann JP, McCullough LA, Matyjaszewski K, Kowalewski T. Mass spectroscopic investigations of nanostructured carbon derived from poly(n-butyl acrylate)-b-polyacrylonitrile copolymers. In Abstracts of Papers, 236th ACS National Meeting 2008 Philadelphia, PA. 

Su, Y.-L., Cheng, W., Li, C., and Jiang, Z. 2009. Rreparation of antifouhng ultrafiltration membranes with poly(ethylene glycol)-graft-polyacrylonitrile copolymers. Journal of Membrane Science 329 246-252. 

Kobayashi, T. Wang, H.Y. Fukaya, T. Fujii, N. Molecular imprint membranes prepared by phase pnversion of polyacrylonitrile copolymers with carboxylic acid groups. In Recognition with Imprinted Polymers, ACS S5Tiiposium Series, 703 Bartsch, R.A., Maeda, M., Eds. Oxford University Press Washington DC, 1998 188-208. 

Polyacrylonitrile copolymers are also used in barrier resins for packaging. One such resin contains at least 70% acrylonitrile and often methyl acrylate as the comonomer. The material has poor impact resistance and in one industrial process the copolymer is prepared in the presence of about 10% butadiene-acrylonitrile rubber by emulsion polymerization. The product contains some graft copolymer and some polymer blend. In another process the impact resistance of the copolymer is improved by biaxial orientation. The package, however, may have a tendency to shrink at elevated temperature, because the copolymer does not crystallize. 

Ogawa H, Studies on the improvement of productivity of high-performance polyacrylonitrile-based carbon-fibers. 1. Effects of comonomer methyl acrylate composition on production of polyacrylonitrile-copolymer-based carbon-fibers, Nippon Kogaku Kaishi, No.5, 464--470, 1994. 

Yamashita, Y. et al. (2008). Carbonization Conditions for Electrospun Nanofiber of Polyacrylonitrile Copolymer. Indian Journal of Fiber and Textile Research, 33, 345-353. 

Bronstein and co-workers (50) reported an in situ method for the preparation of polymer-cobalt nanocomposites by mixing C02(C0)s with a polyacrylonitrile copolymer or an aromatic polyamide in dimethylformamide (DMF). The cobalt carbonyl interacts with DMF giving the complex [Co(DMF)6l +[Co(CO)4] , which is then converted to nanodispersed Co particles by thermolysis. 

In a way similar to PDMS and TEOS, other organic polymers have been functionaliz with alkoxysilyl groups and covalently bonded to silica. Polymers that have been coupled with silica are PTMO-based polyurethane oligomers T69 polyoxazolines , polyimide, poly(arylene ether ketone) poly(arylene ether sulfone), polystyrene polyoxopropylene (PPO) ", polyacrylonitrile, copolymers of methyl methacrylate and allyl methacrylate and cyclophosphazenes. ... 

Kobayashi T, Wang HY, Fujii N. Molecular imprint membranes of polyacrylonitrile copolymers with different acrylic acid segments. Anal Chim Acta 1998 365 81-88. 

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