Cabot Corporation

About: Cabot Corporation is a company organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Carbon black & Carbon. The organization has 1279 authors who have published 1399 publications receiving 36736 citations.

Elastomer composite blends and methods for producing them

Abstract: Elastomer composite blends are produced by novel wet/dry mixing methods and apparatus. In the wet mixing step or stage, fluid streams of particulate filler and elastomer latex are fed to the mixing zone of a coagulum reactor to form a mixture in semi-confined flow continuously from the mixing zone through a coagulum zone to a discharge end of the reactor. The particulate filler fluid is fed under high pressure to the mixing zone, such as to form a jet stream to entrain elastomer latex fluid sufficiently energetically to substantially completely coagulate the elastomer with the particulate filler prior to the discharge end. Highly efficient and effective elastomer coagulation is achieved without the need for a coagulation step involving exposure to acid or salt solution or the like. Elastomer composites are produced. Such elastomer composites may be cured or uncured, and combine material properties, such as choice of filler, elastomer, level of filler loading, and macro-dispersion, not previously achieved. The coagulum produced by such wet mixing step, with or without intermediate processing steps, is then mixed with additional elastomer in a dry mixing step or stage to form elastomer composite blends. The additional elastomer to the coagulum may be the same as or different from the elastomer(s) used in the wet mixing step.

Theory of particle formation and growth in oxide synthesis flames

Abstract: This work discusses those factors which determine ultimate particle size in the synthesis of pyrogenic silica. Pyrogenic or fumed silicas are produced commercially through the combustion of a premixed stream of silicon tetrachloride, hydrogen and air. Because of their minute size, silica particles assume translational velocities and collision frequencies characteristic of large gas molecules. When chemical reaction and nucleation times are short relative to the total formation period; growth, theoretically, approaches a rate which is independent of the early history of the system and is determined solely by the frequency of Brownian collisions. Under these conditions, the logarithm of particle size is directly proportional to the logarithm of growth time. In commercial flames, secondary air is inducted into the flame jet, causing particles to cool below their fusion temperature. Under such circumstances, the growth time and thus the ultimate particle size is a strong function of initial flame tem...

Chemical mechanical polishing slurry for metal layers

Abstract: A slurry for use in chemical-mechanical polishing of a metal layer comprising high purity fine metal oxide particles uniformly dispersed in a stable aqueous medium.

Multiple scattering calculations for technology.

Abstract: A many-flux (discrete ordinate) radiative transfer calculation procedure is described with the goal of making the mathematics easy to learn and use. The major approximation is the neglect of polarization. Emission within the scattering medium is not included, and the formulas are restricted to a scattering medium bounded by parallel planes. The boundary conditions allow for a variety of kinds of illumination, and the surface reflection coefficients at the boundaries of the scattering medium are accurately determined. A comparison is made with the two-flux (Kubelka-Munk) and four-flux calculation methods, and this leads to empirical expressions for the scattering and absorption coefficients in these simple theories, which make them give nearly the same results as exact theories. These empirical expressions provide a very simple method for estimating the absolute reflectance and transmittance of turbid media and greatly increase the utility of the two-flux and four-flux calculation methods. The two-flux equations give excellent results provided the absorption is small compared to scattering and the optical thickness is greater than 5. A comparison with experimental data taken with collimated illumination shows that the four-flux equations give good results at any optical thickness even if the absorption is strong.

Colored pigment and aqueous compositions containing same

Abstract: A surface-modified colored pigment is disclosed which includes a colored pigment having no primary amines and at least one attached hydrophilic organic group, wherein said organic group comprises a) at least one aromatic group, and b) at least one ionic group or ionizable group, or a mixture of an ionic group or an ionizable group. The colored pigment may be blue, brown, cyan, green, violet, magenta, red, orange, yellow, mixtures thereof and the like. The surface-modified colored pigment, due to the hydrophilic groups on its surface, is readily dispersed in a liquid vehicle without the addition of a surfactant or other dispersing aid or additive. The surface-modified color pigment may be used in a variety of aqueous systems including, but not limited to, coatings, paints, papers, adhesives, latexes, inks, toners, textiles and fibers. In addition, an aqueous composition is disclosed including a water-based liquid vehicle and the surface-modified colored pigment described above. Also disclosed is an ink composition including a water-based liquid vehicle and the surface-modified colored pigment described above. Finally, a process is disclosed for preparing the surface-modified colored pigments having no primary amines and at least one attached hydrophilic organic group, wherein said organic group comprises a) at least one aromatic group, and b) at least one ionic group or ionizable group, or a mixture of an ionic group or an ionizable group.