Elsevier

Applied Surface Science

Volume 256, Issue 7, 15 January 2010, Pages 1992-1995
Applied Surface Science

Fabrication and characterizations of a polymer hybrid OA/MA/St-TiO2

https://doi.org/10.1016/j.apsusc.2009.09.033Get rights and content

Abstract

A nano-hybrid composite of octadecyl acrylate/maleic anhydride/styrene (OA/MA/St) encapsulating nano-TiO2 with an average particle size of 30–60 nm was fabricated based on chemical modification of nanotitania. The polymer hybrid OA/MA/St-TiO2 and nano-TiO2 were characterized by infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), static contact angle (CA) as well as transmission electron microscopy (TEM). FT-IR spectra and TGA results suggest that the copolymer OA/MA/St adheres on the surface of nano-TiO2 through physical adsorption and chemical bonding. The calculated reacted OH surface density is about 0.6 OH/nm2, and the modification efficiency is approximately 27.28%. In addition, when the molar ratio of OA/MA/St is 7:2:1, the hybrid shows the strongest hydrophobicity, and its static contact angle reaches as high as 146°. TEM image of the hybrid OA/MA/St-TiO2 reveals that the modified particles have good dispersibility and compatibility with n-hexane.

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)

  • Y. Shirai et al.

    Prog. Org. Coat.

    (1999)
  • X.W. Li et al.

    Appl. Surf. Sci.

    (2003)
  • J. Ji et al.

    Adv. Mater.

    (2006)
  • L.L. Beecreft et al.

    Chem. Mater.

    (1999)
  • R.J. Nussbaumer et al.

    J. Nanopart. Res.

    (2002)
  • S.X. Wang et al.

    J. Mater. Sci. Lett.

    (1999)
There are more references available in the full text version of this article.

Cited by (14)

  • Fabrication of recyclable, superhydrophobic-superoleophilic quartz sand by facile two-step modification for oil-water separation

    2022, Journal of Environmental Chemical Engineering
    Citation Excerpt :

    As shown in Fig. 2a, the raw TiO2, MATC, raw quartz sand and MATC@sand were systematically compared via FTIR. In the FTIR spectra of MATC, the broadband below 1000 cm−1 belongs to the Ti–O–Ti bond stretching mode of TiO2 [32,33]. Compared to the spectrum of the initial TiO2, a collection of new bands was created on the modified TiO2.

  • Surface modification of Sb<inf>2</inf>O<inf>3</inf> nanoparticles with dioctylphthalate

    2019, Applied Surface Science
    Citation Excerpt :

    And the particle surface has unwettability when its contact angle is more than 90° [16]. The higher the contact angle, the lower the surface energy [17]. Therefore, decreasing the contact angle can enlarge the hydrophilicity of the particle surface.

  • Surface modification of calcined kaolin with toluene diisocyanate based on high energy ball milling

    2013, Applied Surface Science
    Citation Excerpt :

    As to the strong exothermic peaks occurred around 820 °C, they were attributed to the further combustion of the residual carbonaceous product under oxygen atmosphere. Water contact angle (CA) provides a direct evidence for the hydrophobicity of solid particles [38,40]. Fig. 8 represents the relationship between the grafting ratio and water contact angle of blank and modified kaolin particles.

  • Functionally modified monodisperse core-shell silica nanoparticles: Silane coupling agent as capping and size tuning agent

    2012, Colloids and Surfaces A: Physicochemical and Engineering Aspects
    Citation Excerpt :

    However, as far as we know, most of above mentioned efficient applications of silica nanoparticles are based on the functionalization of silica nanoparticles [9]. A number of organic compounds including long chain alkyl alcohols or acids, PEG, polymers, organic isocyanates, PMHS and silane coupling agents (SCAs), can be adopted as modifying agent to get organo-functionalized silica nanoparticles for various purposes [10–15]. Among organo-functionalized silica nanoparticles, a series of nanoparticles, whose structure is core–shell and coated by thin organic layer, are of particular interest.

  • Mechanochemically conjugated PMHS/nano-SiO <inf>2</inf> hybrid and subsequent optimum grafting density study

    2011, Applied Surface Science
    Citation Excerpt :

    This result is exactly in good agreement with the result of Fig. 4(a). TGA analysis gives access to an estimated grafting density on nano-SiO2 surface by determining the differences of weight loss between pure and grafted nanoparticles [34]. Thermal analysis experiment was conducted based on Mueller et al. [35].

View all citing articles on Scopus
View full text