Grafting of hyperbranched poly(amidoamine) onto carbon black surfaces using dendrimer synthesis methodology

Abstract

To modify carbon black surface, the surface grafting of hyperbranched poly(amidoamine) onto the surface by using dendrimer synthesis methodology was investigated. Carbon black having amino groups (initiator sites) was prepared by the reduction of surface nitro groups introduced by nitration of aromatic rings. It was found that hyperbranched poly(amidoamine) was propagated from carbon black surface by repeating two processes: (1) Michael addition of methyl acrylate (MA) to surface amino groups and (2) amidation of the resulting esters with ethylenediamine: the percentage of poly(amidoamine) grafting reached to 96.2% after 10th‐generation. The grafting of hyperbranched poly(amidoamine) onto polystyrene‐bead as a model compound of carbon black was also achieved by the above procedures. However, the theoretical propagation of poly(amidoamine) dendrimer was not achieved, because of steric hindrance of grafted polymer. Hyperbranched poly(amidoamine)‐grafted carbon black gave a stable dispersion in a good solvent for poly(amidoamine). Copyright © 2001 John Wiley & Sons, Ltd.

Environmentally Friendly Synthesis of Polymer-Grafted Nanoparticles

“…The ratio of experimental value for calculated value, R, remarkably decreased with increasing repeated reaction cycles. The same tendency was observed in the grafting of PAMAM onto silica nanoparticle in methanol solvent system (Tsubokawa et al, 1988;Tsubokawa et al, 2000;Fujiki et al, 2000;Tsubokawa et al, 2001). www.intechopen.com Based on the above results it is concluded that the theoretical propagation of PAMAM from silica nanoparticle surface was hardly achieved and hyperbranched PAMAM was grafted onto the surface: Figure 16 shows illustration of (A) theoretical PAMAM-grafted silica nanoparticle and (B) hyperbranched PAMAM-grafted silica nanoparticle.…”

“…We have reported that hyperbranched poly(amidoamine) (PAMAM) can be grown from an amino group on silica nanoparticle, chitosan powder, and carbon black surface using dendrimer synthesis methodology in methanol solvent (Tsubokawa et al, 1988c;Tsubokawa et al, 2000;Fujiki et al, 2000;Tsubokawa et al, 2001). Grafting of hyperbranched PAMAM onto silica nanoparticle surface was achieved by repeating two steps, (1) Michael addition of methyl acrylate (MA) to amino group on the surface and (2) amidation of terminal methyl ester group with ethylenediamine (EDA) as shown in Scheme 6.…”

“…www.intechopen.com Based on the above results it is concluded that the theoretical propagation of PAMAM from silica nanoparticle surface was hardly achieved and hyperbranched PAMAM was grafted onto the surface: Figure 16 shows illustration of (A) theoretical PAMAM-grafted silica nanoparticle and (B) hyperbranched PAMAM-grafted silica nanoparticle. This may be due to the fact that (1) complete Michael addition and the amidation with surface amino and ester group hardly proceeded because of aggregation of silica nanoparticles and (2) the grafted chains on the silica surface interfere with the propagation of PAMAM from the surface because of steric hindrance (Tsubokawa et al, 1988;Tsubokawa et al, 2000;Fujiki et al, 2000;Tsubokawa et al, 2001). …”

Surface Grafting of Polymers onto Nanoparticles in a Solvent-Free Dry-System and Applications of Polymer-grafted Nanoparticles as Novel Functional Hybrid Materials

“…The same tendency was observed for grafting of PAMAM onto silica nanoparticles in a methanol solvent system. [30][31][32][33] Figure 3(B) and (C) also show FT-IR spectra of PAMAM-grafted silica nanoparticles with repeated reaction cycles of 3-times and 6-times. The absorption at 1655 cm À1 , characteristic of amide group, increased with repeated reaction cycles.…”

“…28,29 We reported that hyperbranched poly(amidoamine) (PAMAM) can be grown from amino groups on the surface of nanoparticles such as silica, 30,31 carbon black, 32 and chitosan powder 33 using dendrimer synthesis methodology in a methanol solvent.…”