A functionalized inorganic filler includes an inorganic particle which includes a surface functionality. The surface functionality is at least one amine group linked to a surface of the inorganic particle. The functionalized inorganic filler is formed from a reaction between an inorganic particle and an aminosilane compound. A method of making a functionalized inorganic filler includes providing inorganic particles with at least one aminosilane compound to form a reactive mixture and agitating the reactive mixture to form the functionalized inorganic filler. A polymer composite includes an epoxy-based polymer matrix and the functionalized inorganic filler. A reinforced thermoset composite pipe includes the polymer composite.

A silica particle includes: a quaternary ammonium salt, in which the following expressions are satisfied, 0.90F.sub.BEFORE/F.sub.AFTER1.10, and 5F.sub.SINTERING/F.sub.BEFORE20, in which F.sub.BEFORE represents a maximum frequency value of a pore diameter of 2 nm or less in the silica particles before washing, which is obtained from a pore distribution curve in a nitrogen gas adsorption method, F.sub.AFTER represents a maximum frequency value of the pore diameter of 2 nm or less in the silica particles after washing, which is obtained from the pore distribution curve in the nitrogen gas adsorption method, and F.sub.SINTERING represents a maximum frequency value of the pore diameter of 2 nm or less in the silica particles before washing and after sintering at 600 C., which is obtained from the pore distribution curve in the nitrogen gas adsorption method.

A silica functionalized with a siloxane is of the general formula (I), [SiO.sub.4/2].sub.a[R.sup.1SiO.sub.3/2].sub.b [R.sup.3R.sup.1SiO.sub.2/2].sub.c[R.sup.1.sub.3SiO.sub.1/2].sub.d[O.sub.1/2R.sup.2].sub.e (I). The indices a, b, c, d, e each independently have integer values a from 0 to 100, b from 0 to 100, c from 0 to 50, d from 3 to 200, e from 0 to 50, with the proviso that the sum of a, b and c is at least 1 and for more than 50% of the siloxanes in the mixture the sum of a, b and c is 4.

This invention relates to a defoamer active. The defoamer active may include hydrophobized silica particles obtained by treating silica particles with a hydrophobilizing agent. The silica particles may have a BET surface of less than about 150 m.sup.2/g, a surface pH of at least about 10, and a median particle size ranging from about 2 m to about 50 m. The carbon content of the hydrophobized silica particles may not be more than 3%.

Silica particles includes a nitrogen-containing compound. The ratio of the integral C of a signal observed at a chemical shift of 50 ppm or more and 75 ppm or less in a .sup.29Si solid-state nuclei magnetic resonance (NMR) spectrum of the silica particles, the .sup.29Si solid-state NMR spectrum being obtained by cross polarization/magic angle spinning (CP/MAS), to the integral D of a signal observed at a chemical shift of 90 ppm or more and 120 ppm or less in the .sup.29Si solid-state NMR spectrum, that is, C/D, is 0.10 or more and 0.75 or less. The amount X of the nitrogen-containing compound extracted from the silica particles with a mixed solution of ammonia and methanol is 0.1% by mass or more. The amount X of the nitrogen-containing compound extracted and the amount Y of the nitrogen-containing compound extracted from the silica particles with water satisfy Y/X<0.3.

Provided are a nanocomposite body, a method of manufacturing the nanocomposite body, and a nanocomposite film including the nanocomposite body. The nanocomposite body includes: inorganic particles; a polymer matrix; and grafting polymer chains each of which includes a polyol structure, wherein the inorganic particles and the polymer matrix are linked by the grafting polymer chains.

The present invention related to a hollow silica particle including: a shell layer containing silica; and a space formed inside the shell layer, in which the hollow silica particle has a particle density as measured by a dry pycnometer density measurement using helium gas of 2.00 g/cm.sup.3 or more and a particle density as measured by a dry pycnometer density measurement using oxygen gas of lower than 2.00 g/cm.sup.3.

A process for producing cationic colloidal silica which is surface-modified by at least one aminoalkoxysilane having an amino group in cationic form, comprises: (i) under alkaline conditions, reacting a negatively charged colloidal silica with at least one aminoalkoxysilane having an amino group in cationic form at above 20 C. to produce a surface-modified colloidal silica with a net negative surface charge; and (ii) reversing the surface charge of the net negatively charged surface-modified colloidal silica by contacting the net negatively charged surface-modified colloidal silica with an ion exchange resin to obtain a positively charged surface-modified colloidal silica.

Surface treated silica containing particles are combined with a resin to form a liquid prepolymer composition for use in additive manufacturing. A surface treatment on the silica containing particles may participate in polymerization of the composition. The silica containing particles may be colloidal silica or a silica polymer composite particle.

The invention relates to a method for improving a breakdown field strength of polyethylene based on nano-particles grafted with a voltage stabilizer, comprising: 1) dehydration and condensation of nano-particles; 2) carboxyl activation of SDA; 3) grafting with SDA; and 4) preparation of modified nano-composite material. According to the invention, a surface of the nano-particles is modified by an organic group while improving a migration resistance capacity of the voltage stabilizer, and the obtained nano-particles grafted with the voltage stabilizer are doped into a polymer matrix material, so that an electrical property of the matrix material can be improved by both the nano-particles and the voltage stabilizer, and the improvement is stable; and a polyethylene nano-composite material with a significantly improved breakdown field strength can be obtained, thus improving an electrical property of an insulating material, and being beneficial for ensuring the stability of long-term operation of the insulating material.