Acrylamide copolymers preparation

Xanthan-g- poly(acrylamide) copolymer prepared by grafted coploymerization Diclofenac sodium Matrix tablets The matrix tablets were found to release the drug by zero-order kinetics, and it was observed that drug release was faster from the graft copolymer matrix as compared to the xanthan gum matrix. [70]... 

In this article the term acrylamide polymer refers to all polymers which contain acrylamide as a major constituent. Consequendy, acrylamide polymers include functionalized polymers prepared from polyacrylamide by postreaction and copolymers prepared by polymerizing acrylamide (2-propenamide, C H NO) with one or more comonomers. 

Kallin, E., Lonn, H., Norberg, T., and Elofsson, M. (1989) Derivatization procedures for reducing oligosaccharides, Part 3 Preparation of oligosaccharide glycosylamines, and their conversion into oligosaccharide-acrylamide copolymers./. Carbohydr. Chem. 8, 597-611. 

The study was an attempt to correlate polymer structure to its activity in water treatment applications. Copolymers of acrylic acid with N-(hydroxyraethyl)-, N-(2-hydroxyethy1)-, and N-(2-hydroxypropyl) acrylamide were prepared. 

It has been demonstrated that, at temperatures above 125° C, acrylamide copolymers react with amines in aqueous solution to form the corresponding substituted amides in high yields. The process is versatile and a wide variety of N-substituted acrylamide copolymers can be prepared by this method. 

Poly(e-CL-g-acrylamide) copolymers could be readily prepared using electron beam irradiation and Fe2+ ions provided by Mohr s salt as efficient terminators for grafted polyacrylamide chain radicals. Varying the Fe2+ ion concentration [149] enabled the average molecular weight of grafted chains to be varied within wide limits. Poly(DXO) and chemically cross-linked poly(DXO) (Scheme 20) could be grafted with acrylamide under similar conditions [150,151]. 

Copolymers of vinylformamide with acrylamide, methacrylic acid, (II), methacrylates, acrylonitrile, and acrylamide were prepared by Hund [2] and used as flocculants and coagulants in waste water treatment. Sommese [3] prepared poly(vinylamine-co-A-vinylformamide), (III), having molecular weights between 0.8 X 10 and 2.0 X 10 daltons, which were used as coagulants in wastewater treatment. 

Different types of floeculants can be prepared by aminomethylation the amino-methyl derivatives of polyacrylamide represent the most widely adopted class of compounds, which includes high-molecular-weight floeculants (502, 517 in Table 38, 562 in Table 40), and has been widely patented. The large amount of research on these pnxlucts is concerned, in particular, with is(x lcctric points, the content of functionalized co-units, the extent of amido groups hydrolysis, and the use of copolymcrs. -"- Applications of acrylamide copolymers grafted onto starch or other polysaccharides arc also considered. ... 

The microstructure of acrylamide-sodium acrylate copolymers was determined by NMR (36). The monomer sequence distribution was found to conform to Bernouillian statistics and the reactivity ratios of both monomers were close to unity. These results which differ from those obtained for copolymers prepared in solution or emulsion (37) confirmed a polymerization process by nucleation and interparticular collisions. 

Trialkyl-4-vinylbenzyl phosphonium chloride/ acrylamide copolymers. This type of crosslinked trialkyl-4-vinylbenzyl phosphonium chloride (TRVB)/acrylamide (AAm) copolymers were prepared by copolymeiization of TRVB, AAm, and MBAAm (crosslinking monomer) in dimethyl sulfoxide. Three TRVBs with different alkyl chain lengths (butyl, hexyl, and octyl) in phosphonium groups were used. They are abbreviated as TBVB, THVB, and TOVB, respectively. The copolymers obtained have phosphonium groups. Therefore, they are crosslinked cationic polymers. 

Nonaka, T. Yamada, K. Watanabe, T. Kurihara, S. Preparation of superabsorbent polymer hydrogels from trialkyl-4-vinylbenzyl phosphonoium chloride-acrylamide-methylenebis-acrylamide copolymer and their properties. J. Appl. Polym. Sci. 2000, 78, 1883-1884. 

To explore structure-function relationships and optimize their activities, NeuAc-substituted acrylamide polymers were prepared with a variety of appended functional groups (Fig. 22) [99]. These studies generated polymers with very high inhibitory potencies toward HA. For example, an acrylamide copolymer substituted with 10% benzylamine and 20% NeuAc residues had a Ki of 0.6 nM [100]. Both the chelate effect and steric stabilization were mechanisms suggested to contribute to the potent activity of this and related materials (Fig. 5). The NeuAc-substituted acrylamide... 

The effect of branching on the performance of 75% DADMAC/25% acrylamide copolymers in dewatering 100% waste-activated sludge was also investigated. A series of copolymers was prepared by an inverse emulsion method adding up to 0.5 mol % TAMAC (based on DADMAC... 

Several copolymers and condensates of oxidized starches with polymers have been developed. For example, products of starch dialdehyde condensation with acrylamide were prepared for further copolymerization with various monomers to form resins for coatings, molding powders,585 and materials for immobilization of enzymes, for instance, alpha amylase.586 Hypochlorite-oxidized starches were also reacted with acrylonitrile.507,521 Hypochlorite-oxidized starches were allowed to react with allylated starch dialdehyde,587 polycondensates of ammonia-dimethylamine-epichlorohydrin,588 polycondensates of starch dialdehyde with melamine,589 urea433,541,590 capable of precipitation of tannin591, carboxyamides,411 urea and formaldehyde,592 proteins,524,593,594 polyfyinyl alcohol),595 alkylammonium salts,519,596 alkoxyalkylamines,597... 

To elucidate the mechanism of chain association, we prepared three series of N-alkylacrylamide-acrylamide copolymers containing up to 0.75 mol % of Cg, Cio, and C12 N-alkylacrylamide monomers. The copolymerizations were conducted with potassium persulfate as the initiator in an aqueous medium containing a high concentration of sodium dodecyl sulfate surfactant (28). The reaction parameters and solubility of the resulting copolymers are given in Table I. Table I indicates solubility in water of all... 

It may be of interest, that dextran-acrylamide, graft copolymers, prepared in a very similar way to starch-acrylamide, graft copolymers, donot show this aging effect, see page 28 in 3 in 6 ... 

Figure 2.2 Proportions of acrylamide-centred triad sequences for a series of copolymers of sodium acrylate (A) and acrylamide (M), prepared in inverse microemulsions, (a) High conversion polymers (b) low conversion polymers. The curves represent triad proportions calculated using Bernoullian statistics symbols represent experimental triad data (a) AMA (-I-) AMM ( ) MMM is the mole fraction of M in the copolymer. Reprinted with permission from [10]. (1986) American Chemical Society.

Non-quantitative hydrolysis and viscosity producing power of the copolymers described herein permits design of a copolymer based on the application temperature. Lower temperature applications will require less vinyl pyrrolidone in the copolymer. The preparation and general characteristics of vinyl pyrrolidone-acrylamide copolymers are discussed. Particular attention is given the relationship of vinyl pyrrolidone level and the equilibrium level of acrylamide hydrolysis at 121 , and 150 C. 

N-Vinyl-2-pyrrolidone-acrylamide copolymers were prepared by aqueous homogeneous solution polymerization in either distilled water or synthetic seawater. The initial monomer level in the polymerization solutions was either 9.1% or 20% (w/w). The solutions were initiated at either room temperature or 50 C by either 0.50phm or O.lOphm commercial free radical initiators. A temperature controlling water bath was used with the 50 C polymerizations. 

Poly(vinylpyrrolidone-co-acrylamide) (PVP-Am) forms readily as a high molecular weight polymer in aqueous solutions in the presence of free radical initiators. The preparation and characterization of these copolymers has been reported, jhe copolymers prepared for this study were prepared by homogeneous polymerization as 9.1-20% (w/w) solutions. When the polymerization was complete, usually in 8-24 hours, these high solids solutions were rigid and gel-like in appearance. The linearity of the copolymer was evident on dilution, for they dissolved to form gel free, filtrable viscous aqueous solutions. 

The polyelectrolyte acrylamide copolymers poly(acrylamide-cosodium acrylate), poly(acrylamide-co-acrylic acid), and hydrolyzed polyacrylamide were used to study the effect of charge density and charge distribution. The non-polyelectrolyte acrylamide copolymers N,N-dimethylacrylamide and N,N-diethylacrylamide, were prepared to study the effect of N-substituted monomers. 

Poly(dextran-g-acrylamides) from ceric ion initiation (2) Dextran-g-acrylamide copolymers were prepared by ceric ion initiation in water at 25 C using 0.05 M nitric acid. The reactions were conducted for three hours with an initial dextran concentration of 0.0617 M (moles of glucose units) and an acrylamide concentration of l.OM. The molecular weight of the dextran obtained from ICN Pharmaceuticals, Inc. was reported to be = 200,000 to 300,000. Ceric ion concentrations were varied from 2.5 x 10" moles/liter to 10.0 x 10 moles/liter. 

Hydrophobically associating acrylamide copolymers can be prepared by micellar polymerization. These copolymers have short blocks of hydrophobic groups randomly distributed in the backbone. A recent paper reviews the major advances in this area (229). 

This was shown to good effect in an experiment [22] carried out to prepare a series of cationic acrylamide copolymers (60/40 weight ratio) as inverse emulsion polymers using identical polymerisation conditions, in which only the concentration of cross-linking monomer was varied. Subsequent determination of intrinsic viscosity values for this set of polymers showed the results in Table 3.1. 

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