Polymer/layered silicate nanocomposites: a review from preparation to processing

Layered double hydroxides (LDHs) are a class of ionic lamellar compounds made up of positively charged brucite-like layers with an interlayer region containing charge compensating anions and solvation molecules. Delamination of LDHs is an interesting route for producing positively charged thin platelets with a thickness of a few atomic layers, which can be used as nanocomposites for polymers or as building units for making new designed organic-inorganic or inorganic-inorganic nanomaterials. The synthesis of nanosized LDH platelets can be generally classified into two approaches, bottom-up and top-down. It requires modification of the LDH interlamellar environment and then selection of an appropriate solvent system. In DDS intercalated LDHs, the aliphatic tails of the DDS- anions exhibit a high degree of interdigitation in order to maximize guest-guest dispersive interactions. Bellezza reported that the LDH colloids can also been obtained by employing a reverse microemulsion approach.

Recent advances in the synthesis and application of layered double hydroxide (LDH) nanosheets.

A review on polymer–layered silicate nanocomposites

Recent Advances in Bulk Heterojunction Polymer Solar Cells

Structural engineering of polyurethane coatings for high performance applications

https://zenodo.org/record/1197134/files/Elsevier%20paper-AAM-20180302.pdf

Silicon based lithium-ion battery anodes: A chronicle perspective review

Polystyrene−clay nanocomposites have been prepared using a bulk polymerization technique. Three new “onium” salts have been used to prepare the nanocomposites, two are functionalized ammonium salts while the third is a phosphonium salt. By TGA/FTIR, both ammonium and phosphonium treatments have been shown to degrade by a Hofmann elimination mechanism at elevated temperatures. TGA/FTIR showed that the phosphonium treatment is the most thermally stable treatment when compared to the two ammonium salts. The nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, strength and elongation at break, as a measure of the mechanical properties, thermogravimetric analysis, and cone calorimetry. The onset temperature of the degradation is increased by about 50 °C and the peak heat release rate is reduced by 27−58%, depending upon the amount of clay that is present. The mass loss rates are also significantly reduced in the presence of the clay.

Fire Properties of Polystyrene-Clay Nanocomposites

Polystyrene-clay and polystyrene-graphite nanocomposites have been prepared and used to explore the process by which the presence of clay or graphite in a nanocomposite enhances the thermal stability of polymers. This study has been designed to determine if the presence of paramagnetic iron in the matrix can result in radical trapping and thus enhance thermal stability. Nanocomposites were prepared by bulk polymerization using both iron-containing and iron-depleted clays and graphites, and they were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, and cone calorimetry. The presence of structural iron, rather than that present as an impurity, significantly increases the onset temperature of thermal degradation in polymer-clay nanocomposites. Intercalated nanocomposites show an iron effect, but this is less important for exfoliated systems. Polymer-graphite nanocomposites show no difference between iron-free and iron-containing nanocomposites, presumably because the iron is not nanodispersed in the graphite.

Studies on the Mechanism by Which the Formation of Nanocomposites Enhances Thermal Stability

Lignin derivative vanillin when coupled with diamines and diethyl phosphite followed by reaction with echichlorohydrin yields high-performance flame retardant epoxy resins. Biorenewable and environment-friendly flame retardant alternatives to bisphenol A epoxy resins (having plenty of applications such as coatings, adhesives, composites, etc.) have captured great attention due to their ecological and economic necessity. Vanillin, an industrial scale monoaromatic compound from lignin, is a promising sustainable candidate for high-performance polymers, while synthesis of diepoxies is challenging. Meanwhile, bio-based epoxy resins combining high performance and excellent fire resistance are more difficult to be achieved. In this paper, two novel bio-based epoxy monomers EP1 and EP2 were synthesized by one-pot reaction containing Schiff base formation and phosphorus–hydrogen addition between vanillin, diamines, and diethyl phosphite, followed by reacting with epichlorohydrin. Their reactivities are similar to...

Vanillin-Derived High-Performance Flame Retardant Epoxy Resins: Facile Synthesis and Properties

Polymer−clay nanocomposites of styrene and methyl methacrylate have been prepared by bulk, solution, suspension, and emulsion polymerization as well as by melt blending. Two different organic modifications of montmorillonite have been used:  one contains a styryl monomer on the ammonium ion while the other has no double bond. The organic modification as well as the mode of preparation determines if the material will be exfoliated or intercalated. Exfoliation is more likely to occur if the ammonium ion contains a double bond which can participate in the polymerization reaction, but the mere presence of this double bond is not sufficient to always produce an exfoliated system. Solution polymerization always produced intercalated systems. Neither thermogravimetric analysis nor the tensile modulus can be used to evaluate the type of nanocomposite that has been formed.

Jin Zhu

Papers

Silicon based lithium-ion battery anodes: A chronicle perspective review

Fire Properties of Polystyrene-Clay Nanocomposites

Studies on the Mechanism by Which the Formation of Nanocomposites Enhances Thermal Stability

Vanillin-Derived High-Performance Flame Retardant Epoxy Resins: Facile Synthesis and Properties

A Comparison of Various Methods for the Preparation of Polystyrene and Poly(methyl methacrylate) Clay Nanocomposites