N-alkyl Acrylamide Research Articles

Isotactic N-alkyl acrylamide oligomers assume self-assembled sheet structure: first unequivocal evidence from crystal structures

Herein we present the first unequivocal evidence of the ability of isotactic N-alkyl acrylamide oligomers to assume self-assembled sheet-like structures that are reminiscent of protein beta-sheets.

Synthesis of novel intermediates for cyanine dyes by the quaternization of N-heterocycles with acrylamide and N-alkyl acrylamides

The preparation of several novel important heterocyclic N-(2-carbamoyl-ethyl) quaternary salts by 1,4-addition of an appropriate N-heterocyclic base to acrylamide or N-alkyl acrylamides under different reaction conditions in the presence of hydrochloric, hydrobromic or perchloric acid is described. The products have an activated group at 2- or 4-position and are typical precursors of different types of cyanine dyes. The products were characterized by 1H NMR, IR spectra, HPLC–MS spectrometry and elemental analysis.

Temperature-Responsive Chromatography Using Poly-(N-isopropylacrylamide) Hydrogel-Modified Silica

Poly(N-isopropylacrylamide) (PNIPAAm) has the sharpest phase transition of the class of thermo-sensitive N-alkyl acrylamide polymers. We developed a new method of HPLC using packing materials modified with cross-linked poly(N-isopropylacrylamide) (PNIPAAm) hydrogel. A temperature-responsive surface was prepared by polymerization of NIPAAm in the presence of a cross-linker on the silica support. The surface properties and functions of the stationary phases change in response to the external temperature. Therefore it easily changes the interaction of a solute with the surface with a constant aqueous mobile phase. A temperature-responsive elution behavior was observed on the separation of steroids and PTH-amino acids. The method is expected to be applicable to separation in the pharmaceutical and biomedical fields.

Modified release of hydrophilic, hydrophobic and peptide agents from ionized amphiphilic gel networks

Controlled release of hydrophilic and hydrophobic small molecules (vitamin B 12 and progesterone) as well as insulin and interferon was investigated for a terpolymer hydrogel network containing the thermosensitive monomer, N-isopropyl acrylamide (NiPAAM), sodium acrylate and the hydrophobic co-monomer, n- N-alkylacrylamide. A new, micellar-based polymerization method was used to fabricate mechanically robust NiPAAm hydrogels containing small amounts of the other two co-monomers. Drugs and proteins were entrapped directly from aqueous dispersions containing all of the network components stabilized in micelles. Hydrophobic alkyl chain incorporation in these networks influenced NiPAAm gel swelling, gel critical behavior with temperature and drug release kinetics. Increasing gel hydrophobicity imparted by longer alkyl acrylamide chain length and/or increasing alkyl acrylamide content shifted the gel thermal phase transition to lower temperatures and decreased gel swelling. Acrylamide chain-length dependent drug release was also modified over that for gels containing no alkyl co-monomer. Release of insulin and interferon was prolonged over weeks, displaying a zero-order release profile when entrapped (loaded) by in situ network polymerization compared to identical gel rapid release when loaded by usual sorption methods. Hydrophobic micro-structures resulting from micellar stabilized n-alkyl acrylamide monomer clusters in the swelling gels are implicated in creating this release profile.

Nitrogen-containing monomers. III. Reactivity ratios of N-alkyl acrylamides with vinyl monomers

The reactivity ratios in the copolymerizations of N-tert-octyl acrylamide, N-n-octyl acrylamide, and N,N-di-n-butyl acrylamide with styrene and methyl methacrylate have been determined, and the Alfrey-Price Q and e values calculated. The distributed monomer N,N-di-n-butyl acrylamide was found to be more reactive than either N-n-octyl or N-tert-octyl acrylamide, which were of about the same reactivity.

Preparation of N-Alkyl Acrylamides and Methacrylamides by Pyrolysis of the Corresponding Acetoxy Amides

Preparation of N-Alkyl Acrylamides and Methacrylamides by Pyrolysis of the Corresponding Acetoxy Amides