Grafting poly(t‐butyl acrylate) to poly(allylamine) by inverse microemulsion radical polymerization: From comb‐polymer to amphiphilic shell crosslinked polymer nanocapsule

Abstract

An interfacial grafting radical polymerization method for amphiphilic comb copolymer and shell crosslinked polymer nanocapsules was reported. Macropolyradicals on a water soluble long chain polyamine were generated with hydrogen peroxide in the water phase and subsequent grafting radical polymerization of a vinylic monomer at the water/oil interface proceeded at 65°C. In the presence of a crosslinker, the resulting graft copolymer formed a defined core‐shell structure with hydrophilic aqueous core functionalized by the polyamine and a hydrophobic crosslinked polymer shell. The structure of the core‐shell material was characterized by NMR, FTIR, DSC, TGA, SEM, TEM, and the mechanism of the graft polymerization is proposed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1905–1911, 2007

Synthesis of Copper Nanoparticles Using Mixture of Allylamine and Polyallylamine

“…When the concentration of the monomer is low the recombination of the growing chains could form partially cross-linked PAAm. A similar explanation was made in the preparation of grafted copolymers PAAm-g-poly(t-BA) [47]. Figure 5 illustrates a possible mechanism of the polymerization of AAm and other reactions that can be performed in reaction R1.…”

Postsynthetic surface functionalization, encapsulation, and releasing studies of a novel polymer nanocapsule

“…15,19 The chemical composition of the freshly made polymer nanocapsules was confirmed through 1 H-NMR, FTIR analysis, and solvent dispersibility tests with respect to those published before.…”

“…15,19 Briefly, a three-necked round-bottomed flask was equipped with a thermometer, a condenser, an argon inlet, and a magnetic stir bar. The flask was charged with PAA (0.2 g in 5 mL of water), t-BA monomer (4.5 mL), ED (0.7 mL in 5 mL toluene), H 2 O 2 (1.0 mL), and Span 80 (0.17 g).…”

“…It has been previously illustrated that the unmodified nanoparticles, due to the hydrophobic exterior attributed to the t-butyl groups of the ester, exhibited swelling in hydrophobic nonpolar solvents, such as toluene, over time. 19 Upon hydrolysis of the t-butyl groups the surface of the polymer nanocapsules becomes more hydrophilic with formation of carboxylate anions. No longer exhibiting swelling in toluene, the material exhibits partial swelling in more polar organic solvents such as ethyl acetate, DMF and THF indicating some solubility.…”

“…19,21 For the hydrolyzed material, both of these T g s are well represented even with the conversion of the poly(t-butyl acrylate) segment to a poly(carboxylate) segment [ Fig. 2(a)].…”