Acrylate, and Acrylamide Polymers

The properties of a number of vinyl, acrylate, and methacrylate polymers that incorporate ferrocenyl groups in their sidechains were also examined. The incorporation of ferrocene moieties into these classes of polymers resulted in materials with glass transition temperatures much higher than that of their organic analogs.For example, radical polymerization of ferrocenyl methylacrylate (16) allowed for the isolation of polymer 17, whose glass transition temperature (Tg) was 197-210°C versus only 3°C for poly(methyl acrylate) (18). 

Thermosensitive polymers have also been prepared from the AlBN-initiated copolymerization of 7V-ethyl- or A,A-diethyl-acrylamide with vinyl ferrocene. Increasing the amount of organometallic comonomer resulted in decreased LCST values, while oxidation of these polymers resulted in increased LCST values. In all cases, there was less than 3% vinylferrocene incorporated into the polymers. 

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Acrylate and acrylamide polymers have several uses in drilling fluids, one of which is for filtration control. Sodium polyacrylates [9003-04-7] having molecular weights near 250,000 are exceUent temperature-stable filtration control agents for both fresh- and salt water muds, provided the concentration of water-soluble calcium is <400 mg/L (83). The calcium ions are precipitated using a carbonate such as soda ash, before adding the polyacrylate at concentrations up to ca 6 kg/m (3 Ib/bbl). 

Anionic Catalysis Several bulky methacrylates afford highly isotactic, optically active polymers having a single-handed helical structure by asymmetric polymerization. The effective polymerization mechanism is mainly anionic but free-radical catalysis can also lead to helix-sense-selective polymerization. The anionic initiator systems can also be applied for the polymerization of bulky acrylates and acrylamides. The one-handed helical polymethacrylates show an excellent chiral recognition ability when used as a chiral stationary phase for high-performance liquid chromatography (HPLC) [97,98]. 

The mechanism of RAFT polymerization relies on activation of the monomer double bond to enable efficient fragmentation from the intermediate radical, which in turn provides control over the molecular weight of the resulting polymer. It follows that vinyl monomers, for which the double bond is not activated, are still challenging to polymerize efficiently via RAFT. Although attempts have been made to control the polymerization of 1-alkenes [16] and allyl butyl ethers [17], as yet only copolymerization with active monomers (acrylates and acrylamides) has led to a... 

A polymeric monolith is a continuous porous polymeric rod made from a mixture of an initiator, monomers (including a cross-linking monomer), and a porogen (pore-forming solvent) that are polymerized in situ in a column. Tuning of the porous properties is typically achieved with a mixture of solvents such as toluene, THF, or decanol. The rationale for choosing an initiator depends on the mode of initiation and on solubility aspects. A common initiator is 2,2-azo-bis-isobutyronitrile (AIBN). Most polymerizations are radical polymerizations, activating radical formation either thermally [54] or with UV radiation [55]. Common monomers used in the preparation of polymer monoliths are styrene, (meth)acrylate, and acrylamide-based materials. The formation of the monolith... 

Abstract The in vitro enzyme-mediated polymerization of vinyl monomers is reviewed with a scope covering enzymatic polymerization of vitamin C functionalized vinyl monomers, styrene, derivatives of styrene, acrylates, and acrylamide in water and water-miscible cosolvents. Vitamin C functionalized polymers were synthesized via a two-step biocatalytic approach where vitamin C was first regioselectively coupled to vinyl monomers and then subsequently polymerized. The analysis of this enzymatic cascade approach to functionalized vinyl polymers showed that the vitamin C in polymeric form retained its antioxidant property. Kinetic and mechanistic studies revealed that a ternary system (horseradish peroxidase, H2O2, initiator fS-diketone) was required for efficient polymerization and that the initiator controls the characteristics of the polymer. The main attributes of enzymatic approaches to vinyl polymerization when compared with more traditional synthetic approaches include facile ambient reaction environments of temperature and pressure, aqueous conditions, and direct control of selectivity to generate functionalized materials as described for the ascorbic acid modified polymers. 

Carboxymethylcellulose, polyethylene glycol Combination of a cellulose ether with clay Amide-modified carboxyl-containing polysaccharide Sodium aluminate and magnesium oxide Thermally stable hydroxyethylcellulose 30% ammonium or sodium thiosulfate and 20% hydroxyethylcellulose (HEC) Acrylic acid copolymer and oxyalkylene with hydrophobic group Copolymers acrylamide-acrylate and vinyl sulfonate-vinylamide Cationic polygalactomannans and anionic xanthan gum Copolymer from vinyl urethanes and acrylic acid or alkyl acrylates 2-Nitroalkyl ether-modified starch Polymer of glucuronic acid... 

Similar copolymers with N-vinyl-N-methylacetamide as a comonomer have been proposed for hydraulic cement compositions [669]. The polymers consist of AMPS in an amount of 5% to 95%, vinylacrylamide in an amount of 5% to 95%, and acrylamide in an amount of 0% to 80%, all by weight. The polymers are effective at well bottom-hole temperatures ranging from 200° to 500° F and are not adversely affected by brine. Terpolymers of 30 to 90 mole-percent AMPS, 5 to 60 mole-percent of styrene, and residual acrylic acid are also suitable for well cementing operations [253]. 

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