Synthesis and characterization of polycarbonate/ABS/montmorillonite nanocomposites

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Abstract

Polycarbonate (PC)/acrylonitrile-butadiene-styrene (ABS) polymer alloy/montmorillonite (MMT) nanocomposites have been prepared by direct melt intercalation. Their structure and thermal properties are characterized by XRD, TEM, HREM and TGA. The results of XRD and HREM show that nanocomposite is a kind of intercalated structure and the gallery heights of PC/ABS/MMT nanocomposites are almost the same as that of PC/MMT nanocomposite, 3 nm; meanwhile, the nanocomposites improves the thermal stability of PC/ABS polymer alloy matrix.

Introduction

Recently, much attention has been paid to polymer nanocomposites; especially polymer-layered silicate nanocomposites, which represent a rational alternative to conventional filled polymers. Nanocomposite technology has been described as the next great frontier of material science, because by employing minimal addition levels (<10 wt.%), nanoclays significantly enhance mechanical, thermal, dimensional and barrier performance properties [1], [2], [3], [4], [5].

In general, there are four methods to make nanocomposites: exfoliation–adsorption, in situ intercalative polymerization, melt intercalation and template synthesis [2]. Melt intercalation of polymers is a powerful new approach for synthesizing polymer-layered silicate nanocomposites and has been shown to be a more efficient and environmentally-benign alternative to other methods [3].

Polycarbonate (PC)/acrylonitrile-butadiene-styrene (ABS) alloys are well-known commercial polymers. They are widely used in engineering thermoplastics due to an appropriate combination of two components. PC is a resin in which groups of dihydric or polyhydric phenols are linked through carbonate groups. Virtually all general-purpose PCs are based on bisphenol A. PC has high thermal stability and good impact behavior. ABS has easy processability and economical benefits. However, there are few reports about the synthesis of PC/ABS/clay nanocomposites. In this work, we synthesized PC/ABS/clay nanocomposite through direct melt intercalation and studied the morphology and thermal stability of the nanocomposites compared to that of pure PC/ABS alloys.

Section snippets

Materials

The original purified sodium montmorillonite (MMT) was bought from Shanghai, China with a cation exchange capacity of 122 meq/100 g. Hexadecyl trimethy ammonium bromide (C16) was brought from Shanghai Chemistry Company. PC (K-73000, Japan) and ABS (PA-757, Qimei Stock Company, Taiwan) were supplied as pellets.

The preparation of organophilic montmorillonite

Organophilic montmorillonite (OMT) was prepared from MMT by ion exchange reaction using C16 in water according to a reported method [1]. The degradation of OMT at 225 °C is ignored since

Dispersibility of PC/ABS/OMT nanocomposite

Fig. 1 shows the XRD patterns of the PC-OMT, PC/ABS(4/1)-OMT, PC/ABS(3/2)-OMT, PC/ABS(1/4)-OMT and ABS-OMT. Table 1 shows the derived d001 spacings from XRD patterns for MMT, OMT and PC/ABS-OMT composites. The peaks correspond to the (001) plane reflections of the clays. The average basal spacing of MMT increases by organic modification from 1.3 to 2.2 nm, when original MMT was modified by C16. This increased spacing suggests the chain of C16 intercalate into the gallery of MMT and expand it

Conclusion

We prepared PC/ABS/clay nanocomposites by melt blending PC/ABS alloys and organophilic clay (OMT). The morphology of these alloys nanocomposites indicate that it is mainly the ABS molecules which are intercalated into the clay layers rather that the PC molecules. The study by TGA shows that OMT (5 wt.%) will improve the thermal stability of PC/ABS alloys.

Acknowledgements

The work was financially supported by the National Natural Science Foundation of China (No. 50003008), the China NKBRSF project (No. 2001CB409600), Anhui “the tenth five years” tackle key problems project.

References (13)

  • M. Alexandre et al.

    Mater Sci Eng

    (2000)
  • J.W. Gilman

    Appl Clay Sci.

    (1999)
  • R.A. Vaia et al.

    Appl Clay Sci.

    (1999)
  • M. Suzuki et al.

    Polym Degrad Stab

    (1995)
  • S. Wang et al.

    Polym Degrad Stab

    (2002)
  • W. Xie et al.

    Thermochim Acta

    (2001)
There are more references available in the full text version of this article.

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