In this paper, β‐cyclodextrin (CD) was used as effective “green” carbon source to replace pentaerythritol (PER) in an intumescent flame retardant (IFR). The combination of CD with traditional acid resource ammonium polyphosphate (APP) and/or blowing agent melamine (MA) at different weight ratios exhibited outstanding char‐forming ability. It was demonstrated that strong interactions occurred in APP‐CD and MA‐CD systems through thermogravimetric analysis (TGA). Mechanisms of esterification between APP and CD or dehydration between MA and CD were discussed. The APP/MA/CD complexes showed doubled char residue of those calculated based on three single components in nitrogen atmosphere. For instance, the char residue of CD‐APP (at the weight ratio of 1:1) complex was 38 wt% at 700°C, while the calculated char formation was only 19 wt% in N2. After addition of these complexes into polylactic acid (PLA), the flammability of these PLA resins was evaluated by limited oxygen index (LOI) and vertical combustion (UL‐94). The TGA results indicated that the cyclodextrin mixed with APP and MA as a “green” char agent demonstrated outstanding char formation ability for PLA. When the complex contained CD/APP/MA at weight ratio of 1/2/1 and the addition amount of complex in PLA was 20 wt%, the PLA composites showed LOI values of 34.2 and passed UL 94 V0 rating, and the char residue of the PLA composite was 17.4 wt% at 700°C while only 7.4 wt% was achieved for the calculated composition. Copyright © 2011 John Wiley & Sons, Ltd.

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The bulk polymerization of methyl methacrylate and styrene in the presence of an organically modified clay containing a vinyl group that can be involved in the polymerization produces exfoliated nanocomposites. These nanocomposites have been characterized by X‐ray diffraction, transmission electron microscopy, thermogravimetric analysis, mechanical properties, and cone calorimetry. The onset temperature of thermal degradation increases with the mechanical properties. The peak heat release rate is significantly reduced for nanocomposites containing 3 or 5% clay. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1124–1135, 2003

Two methacrylate‐modified clays have been prepared and used to produce nanocomposites of polystyrene and poly(methyl methacrylate) by in situ polymerization. These nanocomposites have been characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), cone calorimetry and the evaluation of mechanical properties. When the clay contains only a single methacrylate unit, the styrene system is exfoliated but methacrylate is intercalated. When two methacrylate units are present on the cation of the clay, both systems are exfoliated. TGA data show that the thermal stability of all the nanocomposites is improved, as expected. The relationships between the fire properties and nanostructure of the nanocomposites are complicated, as shown by cone calorimetry. The conclusions that one may reach using cone calorimetry do not completely agree with those from XRD and TEM. The evaluation of mechanical properties shows an increase in Young's modulus for all nanocomposites along with a decrease in elongation; tensile strength is decreased for methacrylate nanocomposites but increased for styrenics systems. Copyright © 2004 John Wiley & Sons, Ltd.

a b s t r a c tLayered double hydroxides (LDHs) are interesting materials for nanocomposite formation because one can vary the identity of the metals, the anions and the stoichiometry to see the effect of these on the ability of the nano-material to disperse in a polymer and to see what effect dispersion has on the properties of the polymer. In this study, the anions 2-ethylhexyl sulfate (SEHS), bis(2-ethylhexyl) phosphate (HDEHP) and dodecyl benzenesulfonate (SDBS) have been utilized as the charge balancing anions to synthesize organo-LDHs. Nanocomposites of poly(methyl methacrylate) (PMMA) and polystyrene (PS) with organo-LDHs were prepared both by melt blending and bulk polymerization. X-ray diffraction and transmission electron microscopy were used to characterize the morphology of the nanocomposites while the thermal stability and fire properties of nanocomposites were studied by thermogravimetric analysis and cone calorimetry; the mechanical properties are also investigated. In general, it is easier to disperse these organo-LDHs in PMMA than in PS, but the sulfate cannot be dispersed at the nanometer level in either material. The addition of these organo-LDHs does not affect the mechanical properties. The best fire properties are obtained with the sulfonate LDH, SDBS; the reduction in the peak heat release rate is almost 50% for both polymers.