This invention relates to a process of forming a polymeric nanocomposite comprising a continuous polymeric phase formed from a melt processible polymer having a melt processing temperature equal to or greater than about 220 °C and platelet particles having an average thickness equal to or less than about 50 A, and a maximum thickness of about 100 A having a secondary or primary ammonium cationic complex, a quaternary phosphonium cationic complex bonded to surface of said particles, the composite material formed by said process and an article formed from the composite material.

Melt process formation of polymer nanocomposite of exfoliated layered material

Smectites are one of the most important groups of phyllositicates found in soils and sediments, and certainly one of the most difficult to study. New information about the formation mechanisms, impact of structural features on surface properties, and long-term stability of smectites can best be gained from the systematic study of single-phase specimens. In most instances, these specimens can only be obtained through synthesis under controlled conditions. Syntheses of smectites have been attempted (1) at ambient pressure and low-temperature ( 1000~ or pressures >10 kbars), and (4) in the presence of fluoride. Of these approaches, syntheses performed under moderate hydrother- mal conditions are the most numerous and the most successful in terms of smectite yield and phase- purity. Using hydrothermal techniques, high phase-purity can be obtained for beidellites and several transition-metal smectites. However, synthesis of montmorillonite in high purity remains difficult. Starting materials for hydrothermal syntheses include gels, glasses, and other aluminosilicate minerals. The pres- ence of Mg 2+ seems to be essential for the formation of smectites, even for phases such as montmorillonite which contain low amounts of Mg. Highly crystalline smectites can be obtained when extreme temper- atures or pressures are used, but other crystalline impurities are always present. Although the correlation between synthesis stability fields and thermodynamic stability fields is good in many instances, metastable phases are often formed. Few studies, however, include the additional experiments (approach from under- and over-saturation, reversal experiments) needed to ascertain the conditions for formation of thermody- namically stable phases. Thorough characterization of synthetic products by modern instrumental and molecular-scale techniques is also needed to better understand the processes leading to smectite formation.

Synthesis of smectite clay minerals; a critical review

Synthesis of clay minerals

Nanocomposites are manufactured by combining a host material, such as an organic solvent or a matrix polymer and exfoliated intercalates formed by contacting a phyllosilicate with a polymer to adsorb or intercalate the polymer between adjacent phyllosilicate platelets. Sufficient polymer is adsorbed between adjacent phyllosilicate platelets to expand the adjacent platelets to a spacing of at least about 5 A, preferably at least about 10 A (as measured after water removal), up to about 100 A and preferably in the range of about 30-40 A, so that the intercalate easily can be exfoliated, e.g., when mixed with an organic solvent or a polymer melt, to provide a carrier material for drugs and the like, or to provide a matrix polymer/platelet composite (nanocomposite) material - the platelets being exfoliated from the intercalate.

Intercalates and exfoliates formed with oligomers and polymers and composite materials containing same

Graphite nanoplatelets of expanded graphite and composites and products produced therefrom are described. The preferred method of expanding the graphite is by microwaves or other radiofrequency wave treatment of intercalated graphite. The expanded graphite is preferably then crushed to nanometer (substantially all 200 microns or less). The expanded graphite is used in polymer composites. The expanded graphite is particularly useful for batteries, anodes and fuel cells.

Expanded graphite and products produced therefrom

A composite material comprising a resin other than polyamide resin and a layered silicate dispersed therein, said layered silicate having a layer thickness of 7 to 12 Å and an interlayer distance of 30 Å or above. Owing to the layered silicate uniformly dispersed in the resin matrix, the composite material is superior in mechanical characteristics and heat resistance. It also has good water resistance and chemical resistance.

Composite material containing a layered silicate

PURPOSE: To obtain a composite material having excellent mechanical strengths and toughness, by mixing a specific composite material with a monomer for a polyamide and heating the mixture to polymerize the monomer. CONSTITUTION: A laminar clay mineral (A) having a cation exchange capacity of 50W200 milli-equivalents/100g (e.g., montmorillonite) is brought into contact with a swelling agent (B) (e.g., 12-aminododecanoate ion) to obtain a composite material which swells in the molten state of a monomer for a polyamide. In subsequent mixing and/or polymn. stages, the composite material is mixed with a monomer (C) for a polyamide (e.g., e-caprolactam) in the presence of 0.2W2.0 equivalents (based on the amount of the component A) of a polyamine and the mixture is heated to polymerize the component C, thus obtaining a composite material wherein a resin contg. a polyamide is linked to a laminar silicate having a layer thickness of 7W12Å and a distance of at least 30Å between layers at two or more positions on the high-molecular chain of the polyamide through an ion linkage, whereby they are uniformly mixed. COPYRIGHT: (C)1988,JPO&Japio

Composite material and production thereof

Iron phyllosilicates with 1:1 and 2:1 layer structures were prepared from silicic acid, ferrous sulfate and sodium hydroxide. Hydrothermal treatment at 100–200°C of a reaction mixture with an initial Fe/Si ratio of 1.5 gave the 2:1 iron phyllosilicate, whereas a Fe/Si ratio of 2.25 gave the 1:1 phyllosilicate. The 57Fe Mossbauer spectroscopy showed that 60% of the iron in the 1:1 phyllosilicate is ferrous, versus only 3% in the 2:1 phyllosilicate. The values of quadrupole coupling showed that the iron-oxygen tetrahedra and octahedra in the 2:1 phyllosilicate were more deformed than those in the 1:1 phyllosilicate.

Synthesis of 1:1 and 2:1 iron phyllosilicates and characterization of their iron state by mossbauer spectroscopy

Hydrothermal Synthesis of Sepiolite

PURPOSE:To obtain a sintered compact of a high-strength clay mineral without impairing surface activity such as adsorption or catalytic action by calcining a raw material composed of a clay mineral containing sepiolite using a hydrothermal hot-pressing method. CONSTITUTION:A raw material composed of a clay mineral containing at least either of sepiolite and a gel having the composition similar to that of the sepiolite is calcined by a hydrothermal hot-pressing method. Sepiolites and further silica gel or glass fiber may be added to the aforementioned raw material for the purpose of reinforcing the resultant sintered compact or other clay minerals, e.g. bentonite, may be added thereto for the purpose of modifying characteristics. The content of the sepiolites in the raw material is preferably within the range of 5-100wt.%. The mixing ratio of water to the clay mineral is preferably about 1wt.% water based on the raw material of the clay mineral. The hydrothermal pressing is preferably carried out under conditions of 80-350 deg.C treating temperature and 10-1000kg/cm pressure.

Tadashi Mizutani

Papers

Composite material containing a layered silicate

Composite material and production thereof

Synthesis of 1:1 and 2:1 iron phyllosilicates and characterization of their iron state by mossbauer spectroscopy

Hydrothermal Synthesis of Sepiolite

Sintered compact of clay mineral and production thereof