화학공학소재연구정보센터
Langmuir, Vol.24, No.22, 13161-13167, 2008
Strong Deaggregating Effect of a Novel Polyamino Resorcinarene Surfactant on Gold Nanoaggregates under Microwave Irradiation
Gold nanoparticles were prepared by ethylene glycol (EG) reducing gold chloride under microwave irradiation. The EG-stabilized gold colloids varied from red to blue with increasing amounts of EG, due to particle aggregation. Addition of the macrocyclic polyamine 2,8,14,20-tetranonyl-4,6,10,12,16,18,22,24-octa(l-aminoethylcarbamoyl)-m ethoxyresorcinarene (TNMR) reversed nanoparticle aggregation under microwave irradiation and greatly improved their dispersion stability in aqueous Solutions. These effects are likely due to the amphiphilic nature of TNMR, which has a large hydrophilic headgroup with eight amino groups and four hydrophobic chains. Moreover, the large and flexible hydrophilic groups containing more N and O atoms in the TNMR molecule has a strong stretching and penetrating ability in the aqueous solution, and TNMR molecules can easily form a bilayer protecting structure on the surface of gold nanoparticles, which plays a critical role in the color-change process of the EG-stabilized gold colloid.