Abstract: Multimodal polyolefin polymers may be prepared in series-connected polymerization reactors where a prior reactor is a slurry reactor employing light solvent as the slurry medium and hydrogen to limit polymer molecular weight, the polymer product from the prior reactor being substantially freed of hydrogen prior to entry into a subsequent polymerization reactor operating at low hydrogen pressure to produce a high molecular weight olefin. The economics and operating performance of such a series slurry reactor polyethylene process can be significantly improved through the use of an intermediate slurry transfer system and hydrogen removal apparatus that employs flash drums in series in conjunction with a warm recycle solvent slurry diluent.

Abstract: Multimodal polyolefin polymers may be prepared in series-connected polymerization reactors where a prior reactor is a slurry reactor employing light solvent as the slurry medium and hydrogen to limit polymer molecular weight, the polymer product from the prior reactor being substantially freed of hydrogen prior to entry into a subsequent polymerization reactor operating at low hydrogen pressure to produce a high molecular weight olefin. The economics and operating performance of such a series slurry reactor polyethylene process can be significantly improved through the use of an intermediate slurry transfer system and hydrogen removal apparatus that employs flash drums in series in conjunction with a warm recycle solvent slurry diluent.

Abstract: The use of two or more light solvent boiling pool reactors in series allows polymerization of ethylene and comonomer(s) to cost effectively produce bimodal polyethylene copolymers having lower densities than are practically achievable with conventional stirred tank, slurry loop or gas phase reactor technologies. Introducing catalyst to only the first reactor, operating the first reactor at high hydrogen compositions, and using a plurality of series-connected flash drums to remove hydrogen from the first reactor polymer slurry product stream allows for the production of highly homogeneous high molecular weight bimodal polyethylene resins.

Abstract: Multimodal polyolefin polymers may be prepared in series-connected polymerization reactors where a prior reactor is a slurry reactor employing light solvent as the slurry medium and hydrogen to limit polymer molecular weight, the polymer product from the prior reactor being substantially freed of hydrogen prior to entry into a subsequent polymerization reactor operating at low hydrogen pressure to produce a high molecular weight olefin. The economics and operating performance of such a series slurry reactor polyethylene process can be significantly improved through the use of an intermediate slurry transfer system and hydrogen removal apparatus that employs flash drums in series in conjunction with a warm recycle solvent slurry diluent.

Abstract: A rapid acting flow limiting valve is provided for an autoclave processing system. In this environment, each of a plurality of parts is placed in immediate proximity with a tool, then impressed into congruent engagement with the tool by an overlying vacuum bag, the interior of the vacuum bag being subjected to a vacuum via a vacuum manifold connecting all of the parts to a source of the vacuum, the interior of the vacuum bag being subjected to pressure. A first conduit leads from the chamber of the valve housing to the interior of the vacuum bag for its associated part, and a second conduit leads from the chamber to the vacuum manifold. An annular seal is positioned concentrically with an opening from the chamber into the first conduit. A flexible disk-shaped floating piston diaphragm assembly is peripherally fixed to the housing and is movable between an open position distant from the seal and a closed position engaged with the seal to thereby block flow through the first conduit.

Abstract: An aromatic diamino-diol (such as 4,6-diaminoresorcinol) is made by reducing an aromatic halo-dinitro-diol (such as 2-halo-4,6-dinitroresorcinol) with molecular hydrogen in an aqueous mixture containing a noble metal hydrogenation catalyst, an aqueous solvent and about 2 moles of hydrogen halide per mole of aromatic halo-dinitro-diol, plus an additional quantity sufficient to provide a 0.75 to 4 molar solution of the hydrogen halide.

Abstract: A system and method for removing particulate matter from an object being machined or having been machined. A vacuum tube is connected to a source of vacuum and has an intake end adapted to be placed in close proximity to the object being machined. In one embodiment the intake end has a slot such that the intake end can at least partially surround a machining tool. In another embodiment the intake end has standoff buttons that are placed against the object. The vacuum tube can have an inlet cone with a bellmouth shape. Ionized gas is directed at the area proximate the inlet cone and/or machining tool. A vibrator can also be used to vibrate the object.

Abstract: A cathode ray tube includes improved means for supporting scan expansion mesh electrode means, the supporting means comprising knitted metal mesh means in the form of metal braid secured to the mesh electrode means.