N-alkyl acrylamide

T. Deligeorgiev, A. Vasilev and K.-H. Drexhage, Synthesis of novel intermediates for cyanine by the quaternization of V-heterocycles with acrylamide and N-alkyl acrylamides. Dyes Pigm., 67 (2005) 21-26. 

Figure 1. Lower critical solution temperatures of copolymers of N-isopropyl acrylamide with other N-alkyl acrylamides as a function of monomer input ratios.

Table 2 presents the VBC values of all the additives shown in Fig. 10. The order of the VBC values is almost consistent with that of the depressions of the transition temperatures in Fig. 10. Thus it can be concluded that the hydration structure plays an important part in the volume phase transition of N-alkyl-acrylamide gels. 

Consequently, as part of this study, we elected to combine the viscosifying effect of hydrophobic associations with the thermal stability of NVP and the high molecular weight capability of acrylamide. Sepcifically, we synthesized terpolymers of acrylamide, N-alkyl acrylamide, and N-vinyl pyrrolidone (NVP-RAM) and tetrapolymers of acrylamide, N-alkylacrylamide, sodium acrylate, and N-vinyl pyrrolidone... 

Terpolymers of acrylamide, N-alkyl acrylamide, and zwitterionic monomers [e.g. (hydroxyethyl) dimethyl (3<-sulfopropyl) eunmonium methacrylate (SPE) ] were prepared... 

The acrylamide/N-alkyl acrylamide copolymers in this report contain low mole percentages of Cq, Cj q, or substituted... 

Copolymers of acrylamide with N-alkyl acrylamides have been prepared by micellar copolymerization. Compositions of octyl, decyl and dodecylacrylamide were varied from 0.25 to 0.75 mole % in the reaction feed. As mentioned previously, all surfactant was removed by dialysis prior to polymer characterization. The reaction conditions and solubility characteristics of the copolymers can be seen in Table 4. 

For instance, the use of hydrophobically associating water-soluble polymers is a new approach to aqueous fluid mobility control over the last few years [4-9]. Much of this research has focussed on the synthesis of copolymers of acrylamide and comonomers containing long hydrocarbon chains such as laurylacrylate or -methacrylate and N-alkyl acrylamides [8]. Other approaches to this problem have included the synthesis of cellulose-based water-soluble polymers substituted with long hydrocarbon chains [7]. 

The amide group is readily hydrolyzed to acrylic acid, and this reaction is kinetically faster in base than in acid solutions (5,32,33). However, hydrolysis of N-alkyl derivatives proceeds at slower rates. The presence of an electron-with-drawing group on nitrogen not only facilitates hydrolysis but also affects the polymerization behavior of these derivatives (34,35). With concentrated sulfuric acid, acrylamide forms acrylamide sulfate salt, the intermediate of the former sulfuric acid process for producing acrylamide commercially. Further reaction of the salt with alcohols produces acrylate esters (5). In strongly alkaline anhydrous solutions a potassium salt can be formed by reaction with potassium / /-butoxide in tert-huty alcohol at room temperature (36). 

YH Bae, T Okano, SW Kim. Temperature dependence of swelling of crosslinked poly(N,N-alkyl substituted acrylamides) in water. J Polym Sci B 28 923-936, 1990. 

Some information is available on other acrylates. N,N-disubstituted acrylamides form isotactic polymers with lithium alkyls in hydrocarbons (12). t-Butylacrylate forms crystallizable polymers with lithium-based catalysts in non-polar solvents (65) whereas the methyl, n-butyl, sec-butyl and isobutyl esters do not. Isopropylacrylate also gives isotactic polymer with lithium compounds in non-polar solvents (34). The inability of n-alkylacrylates to form crystallizable polymers may result from a requirement for a branched alkyl group for stereospecific polymerization. On the other hand lack of crystallizability cannot be taken as definite evidence of a lack of stereoregulating influence, as sometimes quite highly regular polymer fails to crystallize. The butyllithium-initiated polymers of methylmethacrylate for instance cannot be crystallized. The presence of a small amount of more random structure appears to inhibit the crystallization process1. 

Butler, Thomas, and Tyler (9) have reported on the stereo-specific polymerization of N,N-disubstituted acrylamides by alkyl lithiums. Overberger and Schiller (51) reported on the preparation of crystalline poly-/-butyl vinyl ketone by anionic catalysts in toluene at room temperature. 

When an alcohol, but not the halide, is available one can use the protonic borofluoride of the pyridine and react this with the alcohol in a Mitsunobu reaction <2008TL3663>, and similarly the use of protopyridinium halides allows N-alkylation with acrylamide (Scheme 14) <2005DP21>. 

---