Stimuli‐Responsive SiO2‐graft‐Poly(sodium acrylate) Hybrid Nanoparticles via Cu2+‐Amine Redox‐Initiated Radical Polymerization. Issue 24 (2nd October 2013)

• Record Type: Journal Article
• Authors: Tao, Feng; Chen, Xiaobo; Zhai, Guangqun
• Is Part Of: Macromolecular chemistry and physics. Volume 214:Issue 24(2013:Dec.)
• Page Start: 2792
• Page End: 2801
• Publication Date: 2013-10-02
• Subjects: Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.201300455
• Languages: English
• ISSNs: 1022-1352

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>A novel strategy is proposed to initiate radical graft polymerization of sodium acrylate (NaAAc) from amine‐functionalized SiO<sub>2</sub> nanoparticles (SiO<sub>2</sub>‐NH<sub>2</sub>) to prepare hybrid SiO<sub>2</sub> nanoparticles with NaPAAc chains (SiO<sub>2</sub>‐<italic>g</italic>‐NaPAAc). The polymerization is carried out in aqueous media at ca. 70–90 °C using CuSO<sub>4</sub> as an oxidizing agent. Cu<sup>2+</sup> oxidizes primary amine into aminyl radicals, initiating radical graft polymerization of NaAAc. The hybrid SiO<sub>2</sub>‐<italic>g</italic>‐NaPAAc nanoparticles are characterized by infrared spectroscopy, thermal gravimetric analysis, and X‐ray photoelectron spectroscopy. The morphology is observed by electron microscopy. NaPAAc chains are successfully grafted from SiO<sub>2</sub>‐NH<sub>2</sub>, and the grafting yield is as high as 59.46 wt%. SiO<sub>2</sub>‐<italic>g</italic>‐NaPAAc exhibits a lower degree of aggregation compared with SiO<sub>2</sub>‐NH<sub>2</sub> when dispersed in aqueous media. SiO<sub>2</sub>‐<italic>g</italic>‐NaPAAc exhibits a more stable dispersion in deionized water than SiO<sub>2</sub>‐NH<sub>2</sub>, and addition of a low‐molecular‐weight electrolyte reduced the stability of SiO<sub>2</sub>‐<italic>g</italic>‐NaPAAc in aqueous dispersion, due to the pH‐sensitive polyelectrolyte effect of NaPAAc chains. <boxed-text content-type="graphic" position="anchor" orientation="portrait"><graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgg3zs18vq0" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></boxed-text></p> </abstract>