The Effect of H-Bonding on Radical Copolymerization of Maleic Anhydride with N-tert-Butylacrylamide and Its Characterization

Abstract

The copolymerization reaction between N-tert-butylacrylamide (NTBA) and maleic anhydride (MA) inp-dioxane solution at 65°C using 2,2′-azoisobutyronitrile (AIBN) as an initiator in nitrogen atmosphere was carried out. The chemical structure of the obtained copolymers from a wide range of monomer feeds was determined by elemental analysis (content of N for NTBA units), Fourier transform infrared (FTIR), and 1H-NMR spectroscopy. Also, the amounts of MA units in the copolymers were found using the chemical titration method. An observed tendency toward alternating copolymerization at ≤50 mol% NTBA concentration in monomer feed and relatively high activity of NTBA growing radical was explained by H-bond formation between C=O (anhydride) and NH (amide) fragments during chain growth reactions. Intrinsic viscosity and the molecular weights of the synthesized copolymers depend on the type of comonomer and the amount of NTBA units in the copolymers. The synthesized poly(NTBA-MA)s containing a functional amphiphilic group show both temperature and pH sensitivity and can be used for biological proposes as a physiologically active macromolecular system.

Synthesis and fabrication of high‐potent antimicrobial polymeric ultrathin coatings

“…[28][29][30][31][32][33][34][35][36][37] MA and AM were taken in equal molar ratio and copolymerized. [28][29][30][31][32][33][34][35][36][37] MA and AM were taken in equal molar ratio and copolymerized.…”

“…The optimization of the copolymer was done with respect to different concentrations of the initiator. The chemical shift observed at 31 δ is assigned to the secondary carbon ( 5 C) of the polymer chain backbone 28,[39][40][41][42][43] (Figure 4). As the concentration of initiator (AIBN) increased from 0.0001 to 0.0003 M, the % yield was increased from 90 to 98% because of the availability of enough free radicals for polymerization.…”

“…13 C-NMR spectrum of the copolymer. Similarly, CH 2 stretching is observed at 2931 and 2864 cm −1 , respectively28,[38][39][40][41][42][43] (Figure 2).The chemical shifts at 2.1 δ and 3.2 δ are due to the protons bonded to the tertiary carbon of AM ( 6 CH) and MA unit ( 1,4 CH). Similarly, the peak at 1610 and 1680 cm −1 is attributed to C C and C O stretchings.…”

“…[Color figure can be viewed at wileyonlinelibrary.com] AM: The peak at 3470 cm −1 is due to NH 2 stretching. The chemical shift observed at 2.5 δ is with respect to solvent and 3.4 δ is due to the moisture present in the solvent28,39,[43][44][45] (Figure 3). Moreover, the C N stretching is observed at 1365.65 cm −1 .MA-co-Acrylamide: The peaks at 1780 and 1720 cm −1 are due to carbonyl stretching vibration indicating the presence of MA unit in the copolymer.…”

Poly(thiolactone) homo- and copolymers from maleimide thiolactone: synthesis and functionalization

“…The alternating copolymerization of styrene and maleimide is well-known, 5,51 while in case of NIPAAm only the copolymerization with maleic anhydride has been described so far. 47,52,53 Another reason for the choice of these monomer combinations is that styrene- and NIPAAm-based copolymers with other thiolactone derivatives have been already described. 31,32 However, for these examples the content of thiolactone was limited to a maximum of 30 mol% due to solubility problems, while an alternating copolymerization would allow for the incorporation of up to 50 mol%.…”