Anionic acrylic polymers

The most effective and widely used dispersants are low molecular weight anionic polymers. Dispersion technology has advanced to the point at which polymers are designed for specific classes of foulants or for a broad spectmm of materials. Acrylate-based polymers are widely used as dispersants. They have advanced from simple homopolymers of acryflc acid to more advanced copolymers and terpolymers. The performance characteristics of the acrylate polymers are a function of their molecular weight and stmcture, along with the types of monomeric units incorporated into the polymer backbone. 

The development of monoalkyl phosphate as a low skin irritating anionic surfactant is accented in a review with 30 references on monoalkyl phosphate salts, including surface-active properties, cutaneous effects, and applications to paste and liquid-type skin cleansers, and also phosphorylation reactions from the viewpoint of industrial production [26]. Amine salts of acrylate ester polymers, which are physiologically acceptable and useful as surfactants, are prepared by transesterification of alkyl acrylate polymers with 4-morpholinethanol or the alkanolamines and fatty alcohols or alkoxylated alkylphenols, and neutralizing with carboxylic or phosphoric acid. The polymer salt was used as an emulsifying agent for oils and waxes [70]. Preparation of pharmaceutical liposomes with surfactants derived from phosphoric acid is described in [279]. Lipid bilayer vesicles comprise an anionic or zwitterionic surfactant which when dispersed in H20 at a temperature above the phase transition temperature is in a micellar phase and a second lipid which is a single-chain fatty acid, fatty acid ester, or fatty alcohol which is in an emulsion phase, and cholesterol or a derivative. 

Annaka and Tanaka recently found the presence of several phases in polymer gels between the fully swollen and shrunken phases [46]. This interesting phenomenon was observed in a polyampholyte gel, consisting of acrylic acid (anionic constituent, AAc) and methacryl-amido-propyl-trimethyl-ammonium-chloride (cationic, M APT AC). The chemical structures of these constituents are shown in Fig. 32. A series of copolymer gels were prepared by radical copolymerization, where the total molar concentration of the constituents was kept constant at 700 mM and the molar ratio of AAc/MAPTAC was varied systematically. 

Sodium polyacrylate also named acrylic sodium salt polymer or simply ASAP (repeating unit -CH2-CH(COONa)-) is a polymer widely used in consumer products. Acrylate polymers generally are considered to possess an anionic charge. While sodium neutralized acrylates are the most common form used in industry, there are also other salts available including potassium, lithium, and ammonium. 

Sherrington and coworkers161 have examined the chlorination of phenol by J-butyl hypochlorite in the presence of cross-linked polystyrenes substituted by pendant polymethylene chains terminated with anionic or cationic head groups, as well as some hydrophilic acrylic polymers, in four solvents water, methanol, 1,2-dichloroethane and xylene. The polymers exerted a significant influence on the chlorination, particularly in polar solvents. However, no changes in the regioselectivity of the chlorination, in comparison to homogeneous systems, was observed. 

Although group transfer polymerization does not involve ionic reactions, it is reviewed in this chapter because it bears many practical similarities to anionic polymerizations and is an alternative route to (mcth-)acrylic polymers and block... 

To the best of our knowledge, only a few studies have attempted to prevent the calcification of HEMA-based hydrogels. It has been reported that introduction of carboxylate anions can either prevent or enhance calcification. Cemy et al. (21) found that copolymers of HEMA with 4 wt% methaciylic acid (MAAc) did not calcify under subcutaneous implantation in a rat for 14 months. A similar result was also observed after the implantation of HEMA/MAAc copolymers in the animal urinary tract (22). Other studies carried out in vitro showed that the presence of carboxylate anions significantly reduced the deposition of calcium phosphate (23) and calcium oxalate (24) on acrylic polymers and certain biopolymers. These findings obviously suggest an inhibitory effect of carboxylate anions on calcification. However, by contrast,... 

MMA toward an alkyl radical [302]. Because of its low electron density (e=2.7) [302], this fluoromonomer readily undergoes anionic polymerization with amines and organic and inorganic salts in the presence of 18-crown-6 [301, 303]. However, anionic initiators commonly used for polymerization of MMA such as butyllithium and Grignard reagents fail to polymerize this monomer due to Sn2 addition-elimination [303,304]. All-acrylate polymers for 157 nm imaging have been prepared by radical terpolymerization of 2-trifluoromethyl-acrylate and methacrylate or acrylate [288] (Fig. 90). 

The high affinity of Pd-chloro-complexes to strong anion exchange materials enables the use of various anion exchange sorbents for preconcentration of Pd with simultaneous elimination of cationic interferents. Especially styrene or acrylic polymers cross-linked with divinylbenezene can be applied for enrichment of PGE from large sample volumes (Matsubara et al. 2000 Kovacheva and Djingova 2002 Lesniewska et al. 2006). 

As a companion to the biguanide main-chain polymers, acrylic polymers with biguanide pendant groups were also sjmthesized (Figure 19) (polymer Cll). Polymers were synthesized by free radical polymerization, both as homopolymers and as copolymers of the biguanide monomer with acrylamide. MIC values for these polymers were substantially higher than for the monomer. The authors hypothesized that these results may be due to the fact that the polymers complex with anionic components in the culture media. As a comparison to this... 

PMMA and related acrylic and methacrylic polymers have seen wide application in medicine becairse of their low cost, straightforward polymerization initiation by free radical or anionic mechanisms, ease of processing, and generally inert qirality. Application areas include orthopedics, dentistry, controlled-release systems, cosmetics, and ophthalmology. However, there are many other applications of methacrylate and acrylate polymers in medicine, some with low levels of use and others under development at this time. PMMA is the most widely used of this family of polymers. PHEMA will be addressed separately below. 

Synonyms Acrylic acid homopolymer Acrylic acid polymer Acrylic acid, polymers Acrylic acid resin Acrylic polymer Acrylic polymer resins Acrylic resin Atactic poly(acrylic acid) PAA Polyacrylate Poly (acrylic acid) 2-Propenoic acid, homopolymer Propenoic acid polymer Propenoic acid, polymers, homopolymer Definition Polymer of acrylic acid Empiricai (C3H402)x Formuia [CH2CHCOOH]x Properties M.w. 50,000-250,000 dens. 1.02 kg/l anionic... 

T. E. Lipatova, V. V. Shilov, N. P. Bazilevskaya, and Yu. S. Lipatov, The Formation of Interpenetrating Polymeric Networks on the Basis of Oligoester Acrylate, Styrene, and Divinylbenzene by an Anionic Mechanisms, Br. Polym. J. 9(2), 159 (1977). Oligoester acrylate/PS anionically prepared IPNs. 

Kitano, T. Fujimoto, T. Nagasawa, M. Anionic polymerization of rerf-butyl acrylate. Polym. 7. 1977, 9, 153-159. 

The unique selectivity of modern hyperbranched condensation polymers such as lonPac AS22 allows the simultaneous analysis of mineral acids and a wide variety of polarizable anions with a carbonate-based eluent under isocratic conditions in less than 30 min (Figure 3.131). Even strongly retained analytes such as perchlorate, thiosulfate, and chromate elute as symmetric peaks from this column. In contrast to the respective separation on an acrylate-based anion exchanger in Figure 3.130, fluoride is well separated from the system void. 

Svoboda et al. [160] investigated the emulsion copolymerization and ter-polymerization of VC with vinyl accetate, butyl acrylate and/or ethyl acrylate. The polymerizations proceeded under batch and continuous conditions and were initiated by peroxodisulfates. Anionic emulsifiers (sodium dodecyl sulfate, sodium dodecylbenzene sulfonate,..) and blends of anionic and non-ionic emulsifiers (mostly polyoxyethylene type) were used. Copolymer latexes prepared with emulsifier blends were much more stable than those with an anionic emulsifier. As expected, the copolymers prepared by continuous polymerization gave copolymers with homogeneous composition. In the batch copolymerizations, the shift in the copolymer composition with conversion was observed and particles with broader size distribution were prepared. For example, the batch VC/ethyl acrylate polymer latexes gave particles with a diameter from 180 nra to 320 nm. 

The acrylic monomers that make up cationic polymers are usually the same as those that make up anionic polymers (Table 2.1). Cationic acrylic polymers contain a basic ionizable group, which is usually introduced in one of two ways. The most common method is copolymerization of monomers with an amine group containing monomer, such as dimethylaminoethyl methacrylate (DMAEMA, Fig. 2.6). 

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