Phillips Petroleum Company

Phillips Fibers Corporation

Other

Ronald D Mathis

Jerry O Reed

James S Dix

Gregory M Swisher

Alejandro V Santin

Alonzo G Kitchen

Robert J Martinovich

Gerald E Hagler

Frank J Szalla

John H Underwood

Jerry A Reed

Roger T Shiflet

A conjugated diene/monovinyl substituted aromatic hydrocarbon copolymer is stabilized by the addition of a complex acrylate, in combination with at least one of an alkyl thiopropionate, an organic phosphite and a non-acrylate substituted hindered phenolic compound.

Complex acrylates as stabilizer for conjugated diene/monovinyl aromatic

An automated system is provided for selectively separating resin pellets having a gel count below a specified maximum from pellets having a gel count above the specified maximum, while the pellets are flowing in a pneumatic conveyor. The separation is based on an essentially continuous measurement in which a laser beam is utilized to detect the number of gels in a film made from pellets withdrawn as a sample stream from the main pellet stream. In response to the gel count measurement, a control signal is established that is utilized to manipulate a diverter valve located in the pneumatic conveyor, which diverts pastic pellet flow between a preferred storage means storing pellets having a low gel count and a secondary storage means for storing pellets having a higher gel count. In operation, a hold up tank is provided between the point from which the sample stream is withdrawn and the diverter valve, so that the plastic pellet flow can be delayed in the hold up tank for the amount of time required for the withdrawn sample stream to be converted into the film, whereby the gel count measurement is representative of the pellets passing through the diverter valve.

Plastic pellet sorting apparatus with extruded side-stream monitoring

An automated method is provided for selectively separating resin pellets having a gel count below a specified maximum from pellets having a gel count above the specified maximum, while the pellets are flowing in a pneumatic conveyor. The separation is based on an essentially continuous measurement in which a laser beam is utilized to detect the number of gels in a film made from pellets withdrawn as a sample stream from the main pellet stream. In response to the gel count measurement, a control signal is established that is utilized to manipulate a diverter valve located in the pneumatic conveyor, which diverts plastic pellet flow between a preferred storage means storing pellets having a low gel count and a secondary storage means for storing pellets having a higher gel count. In operation, a hold up tank is provided between the point from which the sample stream is withdrawn and the diverter valve, so that the plastic pellet flow can be delayed in the hold up tank for the amount of time required for the withdrawn sample stream to be converted into the film, whereby the gel count measurement is representative of the pellets passing through the diverter valve.

Automatic method for sorting plastic pellets

Polymer compositions and method for improving processability of compositions of normally solid polymers of arylene sulfides by the addition of at least one of cyanurate and isocyanurate compounds in an amount effective to improve the processability of the composition. In a preferred embodiment the amount of cyanurate and isocyanurate in the total composition is in the range of about 0.1 to about 10 weight percent. The invention is applicable to improving the processing characteristics and other properties of arylene sulfide polymers and filled arylene sulfide polymers.

Polymer compositions

The heat stability of arylene sulfide resins, such as poly(p-phenylene sulfide) resin, is improved by the addition of cure retarders comprising phenolic amide or ester-based antioxidants. The resin compositions of the invention are particularly applicable for reducing gel formation during melt extrusion.

Polymer stabilization

The heat stability of arylene sulfide polymers, such as poly(p-phenylene sulfide) is improved by the addition of cure retarders comprising metal sorbates and, optionally, an alkaline earth metal nitrite.

Stabilization of polyphenylene sulfide

A composition of resinous, non-elastomeric block copolymer of a conjugated diene and a vinylarene in an amount of polyvinylchloride sufficient to provide synergistic notched Izod impact strength as determined by ASTM D-256. A method for preparing this polymeric composition.

Polymer blend composition exhibiting impact resistance

A method of producing poly(arylene sulfide) resin suitable for the commercial production of fibers. The method includes the two stage melt filtration of a suitable poly(arylene sulfide) polymer, e.g., poly(p-phenylene sulfide), through a primary filter having an absolute micron rating of no more than about 125 microns, and through a secondary filter having a maximum absolute micron rating of about 80 or a substantially equivalent filter capacity. Also disclosed are various forms of apparatus for performing the method. In one form the apparatus employs a depth type filter of metallurgically bonded micronic size stainless steel fibers as the primary filter and one or more edge sealed screen combinations each containing one 325 mesh screen as the secondary filter. A secondary filter comprising a mesh screen and a quantity of suitable sand is also disclosed.

Method of producing extrusion grade poly(arylene sulfide)

The heat stability of arylene sulfide resins, such as poly(p-phenylene sulfide) resin, is improved by the addition of cure retarders comprising an aminotriazole. The resin compositions of the invention are particularly applicable for reducing gel formation during melt extrusion.

A method for adjusting the cure rate of a mixture of arylene sulfide polymer particles in which the particles of an arylene sulfide polymer mixture are classified by size groups, the size groups of classified particles are segregated, and at least one size group is removed from the mixture. In a further embodiment at least one size group of classified particles removed from one mixture is added to another mixture of polymer particles. In another embodiment the further use of the segregated size groups of classified particles is based upon a determination of the cure rate of at least one segregated size group of particles.

Method for adjusting arylene sulfide polymer cure rates

A process for the removal of poly(arylene sulfide) deposits on metal surfaces is provided by contacting the deposit with at least one diaryl ether under temperature conditions and for a time sufficient to remove said poly(arylene sulfide) deposits. A process for the cleansing of metal parts having poly(arylene sulfide) deposits is also provided which comprises treatment with a diaryl ether, and thereafter contacting the ether treated part with an alcohol, washing the part with water, drying the part, and thereafter contacting the dried part with concentrated HNO.sub.3 followed by water washing and drying.

Process for cleaning metal surfaces

A process for the removal of poly(arylene sulfide) deposits is provided which comprises contacting said deposits with a solution comprising an alkali metal hydrosulfide in a lactam. In addition, a process for the cleaning of metal parts having poly(arylene sulfide) deposits is provided by contacting the metal parts in the manner as described immediately above, contacting the metal part with a lower alkyl alcohol, washing said metal part with water, drying said metal part, contacting the dried part with concentrated HNO.sub.3 followed by water washing and drying.

Process for cleaning metal surfaces of poly(arylene sulfide) deposits

The curing of arylene sulfide polymers is accelerated by the addition of an effective amount of at least one metal salt of dihydrocarbyldithiophosphinic acid.

The heat stability of arylene sulfide resins, such as poly(p-phenylene sulfide) resin, is improved by the addition of cure retarders comprising Group IIA or Group IIB metal salts of fatty acids. The resin compositions of the invention are particularly applicable for reducing gel formation during melt extrusion.

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Bartlesville, OK, United States of America

Ronald D Mathis