Acrylamide derivatives, copolymerization

The relative proportions of triads is determined by the synthetic conditions chosen as described above for acrylic acid copolymers of acrylamide derived by either direct copolymerization or by hydrolysis. Also, the polymerization pH has a considerable effect on the reactivity in acrylamide/acrylic acid copolymerization. 

Many different types of responsive gels have been synthesized by various techniques. Copolymerization/crosslinking of monofunctional and polyfunctional monomers has been extensively used to produce responsive gels of vinyl monomers, especially of a wide variety of acrylamide derivatives such as N-isopropylacrylamide, acrylic acid, and diethylacrylamide [4-11, 21-36]. Crosslinking of linear polymers by either chemical means or y-radiation has also been used to produce a wide range of responsive gels. The precursor polymers... 

Copolymerization of St with Acrylamide Derivatives. The dependence of the M2 fraction in instantaneously-formed polymer on the total conversion is compared among four kinds of acrylamides-St copolymerizations at f = 0.4 (Figure 4) (14). HMA and DMA resemble AA concerning the copolymerization mode, that is, their reaction course is divided into three stages. On the other hand MA copolymerizes in a different mode. 

A different strategy for preparing enzymes for immobilization is to introduce vinyl groups by alkylating or acylating enzymes with activated vinyl monomers [40]. The modified enzymes are then polymerized with mono- and bifunctional acrylamide derivatives to yield elastic particles of irregular shape after crushing of the formed polymer blocks. Such copolymerization processes have yielded stable industrial biocatalysts for pharmaceutical application which are especially suited for stirred tank applications [41]. 

Like PNlPAAm and some other acrylamide derivative polymer gels, the poly (NlPAAm-co-AAmPA) gels swell at low temperature and de-swell at elevated temperature. At pH 2.1.5 the comonomer is completely protonated. The hydrophi-licity of the comonomer is very similar to A-isopropyl acrylamide (NIP A Am). No differences in the swelling curves could be seen. At pH 7.7 the comonomer is charged. The degree of swelling is strongly affected by the copolymerization ratio. The transition behaviour under these circumstances is not very well pronounced (Beebe et al. 2000). 

The latex copolymerization of styrene with A -methylacrylamide does not follow the three stage process observed with the other acrylamide derivatives. 

Amylopectins. — The effects of acrylamide graft copolymerization on the solution properties of amylopectin have been discussed. Amylopectin has been dyed with DyAmyl-L and used in this form as a substrate for the assay of a-amylase. Amylopectin has been treated with isocyanate derivatives of 4-amino-( 1,1-dimethyl ethyl)-3-(methylthio)-l,2,4-triazin-5(4/f)-one ( metribuzin ) or acid chloride derivatives of 2,4-dichlorophenoxyacetic acid ( 2,4-D ) and 2,2-dichloropropionic acid ( dalapon ), to produce controlled-release polymeric pesticide systems. The solvent system utilized for these reactions, a lithium chloride or bromide salt in AW-dimethylacetamide, allows dissolution of the reactant salt and facilitates analysis of the polymer product by such techniques as i.r., U.V., and n.m.r. spectroscopies and gel permeation chromatography. Derivatives of other naturally occurring polysaccharides, including amylopectin, cellulose, chitin, and dextran, were also prepared. 

A laboratory zinc-polymer coating developed by Hisamoto et al. (1992) permits direct painting without phosphating. The preferred polymer was based on acrylamide modified by copolymerization of epoxy groups with acrylamide derivative monomer for best corrosion resistance, modification should exceed 50 mol%. 

Phenothiazines are well known redox systems and poly(2-vinyl phenothiazine) (IV) is readily oxidized "by agents like ferric chloride or bromine and by oxygen in presence of light. Shigehara and COworkers synthesized the acrylamide derivatives of the thiazine dyes (v), Thionin and Azure B, and copolymerized them with N vinyl pyrrolidone by free radical methods to give wa ter soluble polymeric dyes. ... 

Since 2000, hving radical polymerization has allowed the synthesis of block copolymers with controlled molecular weight and a narrow MWD using many monomer combinations, as shown in Figs. 4 and 5 [71]. Block copolymerization with hydrophilic or thermoresponsive acrylamide derivatives 11,12 has been examined [72-77]. Block copolymers having hydrophiUc segments such as PNlPAM-poly[(meth)acrylic acid] (13) [78-80], PNIPAM-poly(sulfonic acid) (14) [81,82], PNIPAM-poly(2-hydroxyethylacrylate) U5) [83], and PNIPAM- poly](2-dimethylamino)ethyl methacrylate]-co-poly(2-hydroxyethyl methacrylate) (16) [84] were prepared. These formed polymer micelles in response to variation of the temperature. For example, Muller et al. have synthesized PNIPAM-poly(acrylic acid) with low polydis-... 

The (meth)acryloyl moiety is sometimes incorporated in cholic acid at the COOH position through a ethylenediamine linker [222,223]. The conjugate monomer is copolymerized with acrylamide derivatives to produce copolymers with tunable thermo-responsiveness. A monomer of this type with PEG oligomer between methacryloyl and cholic acid moieties has also been prepared and polymerized by ATRP, giving a comb-shaped polymer with relatively low MW and low PDI [224]. 

Methylol Formation. Polyacrylamide reacts with formaldehyde to form an /V-methylo1 derivative. The reaction is conducted at pH 7—8.8 to avoid cross-linking, which will occur at lower pH. The copolymer can also be prepared by copolymerizing acrylamide with commercially available A/-methylolacrylamide [924-42-5] C4H2NO2. These derivatives are useful in several mining appHcations (49,50). They are also useful as chemical grouts. 

Radical copolymerization is used in the manufacturing of random copolymers of acrylamide with vinyl monomers. Anionic copolymers are obtained by copolymerization of acrylamide with acrylic, methacrylic, maleic, fu-maric, styrenesulfonic, 2-acrylamide-2-methylpro-panesulfonic acids and its salts, etc., as well as by hydrolysis and sulfomethylation of polyacrylamide Cationic copolymers are obtained by copolymerization of acrylamide with jV-dialkylaminoalkyl acrylates and methacrylates, l,2-dimethyl-5-vinylpyridinum sulfate, etc. or by postreactions of polyacrylamide (the Mannich reaction and Hofmann degradation). Nonionic copolymers are obtained by copolymerization of acrylamide with acrylates, methacrylates, styrene derivatives, acrylonitrile, etc. Copolymerization methods are the same as the polymerization of acrylamide. 

Radical polymerization of diallylamine derivatives produce water-soluble polymers of low molecular weight [22,55-57]. In order to increase the molecular weight, acrylamide has been copolymerized with these diallylamine derivatives to produce cationic polymers with variable charge density depending on the content of the structural units of pyrrolidinium rings and acrylamide in polymeric chains [22,55,58-61]. 

Poly(acrylamide-diallylethylamine-HCl) (cationic polyacrylamide pAM-HCl) was prepared by gamma radiation-initiated copolymerization of acrylamide with di-allylethylamine-HCI in aqueous solution at the optimum composition for copolymerization of acrylamide with diallylamine derivatives [61]. 

Comparing the reactivity ratios of the DADMAC/AAM copolymerization with results of the copolymerization of other cationic monomers with AAM, significant differences can be identified. The differences between rx and r2 are much lower, and the cationic monomer even reacts preferentially during the copolymerization. As an example, for cationic methacrylic esters and methacrylamid derivatives, 1 nonideal copolymerization preferring the cationic component. For the cationic analogs of acrylic acid and acrylamide, 0.34azeotropic copolymerization, preferring the cationic monomer only at low content in the comonomer mixture. 

Emulsifier-Free Emulsion Copolymerization of Styrene with Acrylamide and Its Derivatives... 

This paper deals with the copolymerization of styrene with acrylamide and its derivatives in emulsifier-free aqueous media. It is expected that the effects of acrylamides on the nucleation and stabilization of particles differ from those of ionic comonomers. The reaction mechanism, the characteristics of the latices prepared, and the effect of the properties of acrylamides on them are discussed. 

The First Stage. The preferential polymerization of AA at the initial stage of copolymerization means that the main reaction locus is the aqueous phase just as Juang and Krieger pointed it out for the aqueous copolymerization of St with sodium styrenesul-fonate ( SSS ) (9). In the St-SSS system, SSS polymerized preferentially up to a few percent conversion under the condition of SSS/St (w/w) - 0.014. Copolymerization of hydrophobic monomer with a large amount of hydrophilic comonomer was considered to yield a greater amount of information with respect to the reaction mode. By use of a relatively large amount of AA or its derivatives the characteristic reaction mode of the copolymerization of St with acrylamides could be clarified. 

Fullerenes and their water soluble derivatives are of great deal interest for scientific research due to their biological activity [1]. Therefor, the problems of modification and functionalization of nanomaterials to obtain their water soluble derivatives are very challenging task. In present work we have investigated low-temperature y -induced copolymerization of vinyl monomers such as acrylamide and acrylic acid with fullerene C6o to obtain their water soluble polymers containing fullerene. 

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