Acrylic Polymer Solutions

Acrylic Polymer Solutions Poly(acrylic acid) 

Polyfsodium acrylate) Polyfmethacrylic acid) Poly(methyl methacrylate) 

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Acrylates are primarily used to prepare emulsion and solution polymers. The emulsion polymerization process provides high yields of polymers in a form suitable for a variety of appHcations. Acrylate polymer emulsions were first used as coatings for leather in the eady 1930s and have found wide utiHty as coatings, finishes, and binders for leather, textiles, and paper. Acrylate emulsions are used in the preparation of both interior and exterior paints, door poHshes, and adhesives. Solution polymers of acrylates, frequentiy with minor concentrations of other monomers, are employed in the preparation of industrial coatings. Polymers of acryHc acid can be used as superabsorbents in disposable diapers, as well as in formulation of superior, reduced-phosphate-level detergents. 

Solution Properties. Typically, if a polymer is soluble ia a solvent, it is soluble ia all proportions. As solvent evaporates from the solution, no phase separation or precipitation occurs. The solution viscosity iacreases continually until a coherent film is formed. The film is held together by molecular entanglements and secondary bonding forces. The solubiUty of the acrylate polymers is affected by the nature of the side group. Polymers that contain short side chaias are relatively polar and are soluble ia polar solvents such as ketones, esters, or ether alcohols. As the side chaia iacreases ia length the polymers are less polar and dissolve ia relatively nonpolar solvents, such as aromatic or aUphatic hydrocarbons. 

Adhesives. Acryhc emulsion and solution polymers form the basis of a variety of adhesive types. The principal use is in pressure-sensitive adhesives, where a film of a very low T (<—20 " C) acrylic polymer or copolymer is used on the adherent side of tapes, decals, and labels. Acrylics provide a good balance of tack and bond strength with exceptional color stabiUty and resistance to aging (201,202). AcryUcs also find use in numerous types of constmction adhesive formulations and as film-to-film laminating adhesives (qv). 

Amine salts of acrylate ester polymers, which are physiologically acceptable and useful as surfactants, are prepared by transesterifying alkyl acrylate polymers with 4-morpholinethanol or alkanolamines and fatty alcohols or alkoxyl-ated alkylphenols and neutralizing with phosphoric acid. This polymer salt (pH of a 10% aqueous solution = 5.1) was used as an emulsifying agent for oils and waxes [70]. 

HS-GC methods have equally been used for chromatographic analysis of residual volatile substances in PS [219]. In particular, various methods have been described for the determination of styrene monomer in PS by solution headspace analysis [204,220]. Residual styrene monomer in PS granules can be determined in about 100 min in DMF solution using n-butylbenzene as an internal standard for this monomer solid headspace sampling is considerably less suitable as over 20 h are required to reach equilibrium [204]. Shanks [221] has determined residual styrene and butadiene in polymers with an analytical sensitivity of 0.05 to 5 ppm by SHS analysis of polymer solutions. The method development for determination of residual styrene monomer in PS samples and of residual solvent (toluene) in a printed laminated plastic film by HS-GC was illustrated [207], Less volatile monomers such as styrene (b.p. 145 °C) and 2-ethylhexyl acrylate (b.p. 214 °C) may not be determined using headspace techniques with the same sensitivities realised for more volatile monomers. Steichen [216] has reported a 600-fold increase in headspace sensitivity for the analysis of residual 2-ethylhexyl acrylate by adding water to the solution in dimethylacetamide. 

Carboxylate-based brine solution, 9 33 Carboxylated acrylic polymers, in water-based inks, 14 326 Carboxylation, 9 282 Carboxyl cure sites, in ethylene-acrylic elastomers, 10 698... 

Doped silicon, conductivity in, 23 35 Doped/undoped electrochromic organic films, 6 580-582 Dope-dyeing, 9 197 Dope-making process, in acrylic fiber solution spinning, 11 204 Dope solids, in air gap spinning, 11 209 Doping, 23 838—839 calcium, 23 842-844 conducting polymers, 7 528-529... 

It should be noted that the absence of matrix effect when the monomer is only associated in the cyclodimeric form suggests that structure I is more stable than the association of the monomer with the polymer and that therefore long ordered structures of type III do not arise. In very dilute acrylic acid solutions in hydrocarbons or chlorinated compouds a matrix effect (autoacceleration) is again observed. This is believed to arise as a result of a structure III formed by the association of the polymer with "free" monomer (4). 

Carboxylated polymers can be prepared by mechanical treatment of frozen polymer solutions in acrylic acid (Heinicke 1984). The reaction mechanism is based on the initiation of polymerization of the frozen monomer by free macroradicals formed during mechanolysis of the starting polymer. Depending on the type of polymer, mixed, grafted, and block polymers with a linear or spatial structure are obtained. What is important is that the solid-phase reaction runs with a relatively high rate. For instance, in the polyamide reactive system with acrylic acid, the tribochemical reaction leading to the copolymer is completed after a treatment time of 60 s. As a rule, the mechanical activation of polymers is mainly carried out in a dry state, because the structural imperfections appear most likely here. 

Butvl Acrylate (BAl Solution Copolymers. Polymerizations were run with 0.30 mmol of comonomer per calculated g of polymer solids premixed with BA Reactor Charge X g comonomer, (50-X) g of butyl acrylate, 120 g of dry toluene, 0.15 g of 2,2 -azob1s1sobutyron1tr11e (AIBN). 

Now back to our alien autopsy. As it turns out, the creature is just a sophisticated super slurper. His flesh is made of acrylic polymers (partially hydrolyzed acrylonitrile, for those of you interested in the nitty gritty details), which have been chemically linked to starch to achieve just the right gooey consistency when swollen with water. By immersing the super slurper in a salt solution, we can produce a deflating effect. The alien withers away, but I hope his chemistry is no longer alien. 

The dipole moments of model compounds of the diads of phenyl- and chlorophenyl-substituted acrylate polymers are measured in benzene solution. The results are interpreted in terms of the RIS model. A four-states model used in the analysis of PMA, after adjustment of some parameters, is able to reproduce the experimental values. 

For polystyrene fractions in diethyl phthalate solution (30000average value of 1.6 x 10 18 ( 50%). In dilute solution e/36M is 1.27 x 10 18 for polystyrene (21). No systematic variations with concentration, molecular weight or temperature were apparent, the scatter of the data being mainly attributable to the experimental difficulties of the diffusion measurements. The value of Drj/cRT for an undiluted tagged fraction of polyfn-butyl acrylate) m pure polymer was found to be 2.8 x 10 18. The value of dilute solution data for other acrylate polymers (34). Thus, transport behavior, like the scattering experiments, supports random coil configuration in concentrated systems, with perhaps some small expansion beyond 6-dimensions. 

The post-modification reactions of acrylamide polymers were run as follows.6 A solution of poly(acrylamide[75mol%]-acrylic acid) (150 g, 27.5% in water) and sodium formaldehyde bisulfite (15.5 g), pH 4.3, was heated to 150° C and maintained at that temperature for four hours in a 300 ml Parr reactor which was equipped with a mechanical stirrer and a thermocouple. The pH of the resulting polymer solution at room temperature was 5.9. 

The formation of block copolymers from styrene-maleic anhydride and acrylic monomers was also indicated by pyrolytic gas chromatography and infrared spectroscopy. A comparison of the pyrograms of the block copolymers in Figure 7 shows peaks comparable with those obtained when mixtures of the acrylate polymers and poly(styrene-co-maleic anhydride) were pyrolyzed. A characteristic infrared spectrum was observed for the product obtained when macroradicals were added to a solution of methyl methacrylate in benzene. The characteristic bands for methyl methacrylate (MM) are noted on this spectogram in Figure 8. 

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