Fabrication and characterizations of a polymer hybrid OA/MA/St-TiO2
Introduction
Nowadays, nanoparticles have attracted great attention due to their novel aspects of surface physics and important applications in many fields [1]. Their minisize effect, surface effect and macroscopic quantum tunnel effect make them differ a lot from bulk materials [2]. Inorganic nanoparticles, as an important part of nanomaterials, are difficult to be dispersed in non-polar solvents stably because of their high surface energy and tremendous specific surface area [3]. In order to solve the problem of nanoparticle aggregation, one of the most efficient methods being used is to introduce organic polymers onto the surfaces of inorganic particles to fabricate hybrid composites, which combine typical properties of organic polymers with the advantages of inorganic nanoparticles [4], [5]. Organic polymers introduced onto the surface of particles are considered to interfere with the aggregation of the particles and improve the affinity of the surfaces with the organic solvents [6], [7]. Wang et al. [4] reported the use of the copolymer PSMA (styrene/maleic anhydride) as a modification agent to modify nano-TiO2. The nanocomposites PSMA-TiO2 can improve the dispersibility stability of nano-TiO2 in PSMA matrix. Shirai et al. [5] reported synthesis of copolymers by graft polymerization of various vinyl monomers, and their effective introducing onto the surface of nano-TiO2.
It is well known that styrene, maleic anhydride and octadecyl acrylate polymerize alternatively and form a copolymer (OA/MA/St) with a number of anhydride groups on backbone chains. These functional groups are able to anchor nano-TiO2 and prevent them from aggregating. In the present paper, a series of OA/MA/St copolymers was synthesized, and they were employed for modification of nano-TiO2. OH surface density on the surface of nano-TiO2 was calculated from TGA and FT-IR. CA as well as TEM was used to characterize and evaluate the results of the modification.
Section snippets
Materials
Maleic anhydride (A.R.) and benzoyl peroxide (A.R.) were obtained from Shanghai Chemical Works “Lingfeng”, China. Styrene (A.R.) and xylene (A.R.) obtained from Shanghai Chemical Works, China were used after reduced pressure distillation. Octadecyl acrylate (m.p., 32–34 °C) was obtained from Technology Center of Juhua Group, Zhejiang, China. Nano-TiO2 (average particle size, 30–60 nm, purification, 98%) was obtained from Nanjing Titanium Dioxide Chemical Co., Ltd., China.
Synthesis of OA/MA/St
Solution polymerization
Relationship between the contact angle value of the hybrid against water and the molar ratio of octadecyl acrylate in copolymer
A series of OA/MA/St copolymers was synthesized, and they were employed for modification of nano-TiO2. According to Young Equation cos θ = (γls − γs)/γl, contact angle is one of the factors that can be used to evaluate the hydrophobicity of solid particles [8]. Fig. 2 shows the correlation of contact angle value of the hybrid against water with the molecular ratio of octadecyl acrylate in copolymer. As we know, nano-TiO2 without modification exhibits good hydrophilicity because of the hydroxyl
Conclusion
A polymer hybrid OA/MA/St-TiO2 was fabricated by modification of nanotitania. Thermogravimetric analysis suggests that the reacted OH surface density is about 0.6 OH/nm2, and the modification efficiency is approximately 27.28%. When the molar ratio of octadecyl acrylate in copolymer is seven, the polymer hybrid OA/MA/St-TiO2 shows the strongest hydrophobicity, and its static contact angle against water is 146°. TEM image of the hybrid OA/MA/St-TiO2 in n-hexane reveals that the modified
References (13)
- et al.
Prog. Org. Coat.
(1999) - et al.
Appl. Surf. Sci.
(2003) - et al.
Adv. Mater.
(2006) - et al.
Chem. Mater.
(1999) - et al.
J. Nanopart. Res.
(2002) - et al.
J. Mater. Sci. Lett.
(1999)
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