Poly Phillips process

The more or less simultaneously developed Phillips process likewise uses a xylene solution, but at lower pressures (30-50 bar) and temperatures (150°C) and with a partially reduced chromic oxide on aluminum oxide or aluminum silicate as supporting agent. The catalyst, which is used in relatively large quantities (10% of ethylene content), is activated by heating and filtered off after an almost 100% yield of poly(ethylene) has been obtained. The poly(ethylene) precipitates from the cooled solution the solvent, before distillation, still contains low-molecular-weight poly-... 

Poly(phenylene sulfide), prepared by the Phillips process, is a highly crystalline polymer that can be used for long times at high temperatures... 

Poly(1-butene co ethylene co 1-hexene) n A copolymer produced commercially by the Phillips process and containing up to 5% butene-1. It is similar to high density polyethylene but has a slightly lower density and better resistance to creep. 

Bayer marketed PPS compounds in the United States under the trade name Tedur, but the company has exited the PPS business. PPS is also marketed in the United States by GE Plastics, whose source of neat resin is Tosoh Corporation of Japan. GE Plastics markets PPS under the trade name Supec PPS. Patent activity by Tennessee Eastman describes an alternative process for the production of poly(phenylene sulfide/disulfide), although samples of such product have not appeared as of early 1996. Both Phillips and Hoechst Celanese have aimounced plans to debotdeneck their existing U.S. faciUties in order to meet anticipated market growth. 

Poly(phenylene sulfide) (PPS) is another semicrystalline polymer used in the composites industry. PPS-based composites are generally processed at 330°C and subsequently cooled rapidly in order to avoid excessive crystallisation and reduced toughness. The superior fire-retardant characteristics of PPS-based composites result in appHcations where fire resistance is an important design consideration. Laminated composites based on this material have shown poor resistance to transverse impact as a result of the poor adhesion of the fibers to the semicrystalline matrix. A PPS material more recently developed by Phillips Petroleum, AVTEL, has improved fiber—matrix interfacial properties, and promises, therefore, an enhanced resistance to transverse impact (see PoLYAffiRS containing sulfur). 

Lastly the Phillips and the Standard Oil (Indiana) Processes both yield high density poly(ethylenes), using relatively low pressures and temperatures. Details of these processes are given in Table 1.1. 

The commercial production of high-density polyethylene started almost at the same time in late 1956 by Phillips using a chromium-based catalyst in a medium-pressure process and by Hoechst using a Ziegler catalyst in a low-pressure process. Polypropylene production began in Montecatini and Hercules plants in 1957. Poly(l-butene) and poly(4-methyl-1-pentene) have been produced in small commercial quantities since about 1965. The commercial production of ethylene/propylene-based rubbers started in 1960 [241]. 

Over the past 20 years a considerable chemical research effort was devoted to developing new high temperature polymers. It is interesting to note that some of these materials are now finding new applications and solutions to old problems of processing through blending. A commercial series of products trade-named Tribolon XT has been announced which are based on an aromatic polymide (Upjohn s 2080) with Phillips poly(phenylene sulfide), trade-named Ryton. A recent publication (88) describes some of the unique characteristics of this new family of materials. 

Poly(p-phenylene sulfide) was first reported in 1897 by Genvresse [92] who reported an insoluble resin prepared by the reaction of benzene with sulfur in the presence of aluminum ehloride. A variety of other procedures were reported to yield similar resins. Macallum [93] in 1948 reported a novel procedure that yielded an improved resin. Lenz and co-workers [94-96] modified the procedure and Edmonds and Hill [97] of the Phillips Petroleum Co. developed a commercially successful process. The material is now marketed under the trade name Ryton [98]. The crystallinity of the polymer has recently been reported [99-101]. 

Poly(phenylene sulfide) (PPS) is the thio analogue of poly(phenylene oxide) (PPO) [57]. The first commercial grades were introduced by Phillips Petroleum in 1968 under the trade name Ryton. Other manufacturers also have introduced PPS (e.g., Tedur by Bayer). The commercial process involves the reaction of p-dichlorobenzene with sodium sulfide in a polar solvent. 

C. E. Ash, J. F. Geibel, and H. D. Yelton. Process for preparing high molecular weight poly(arylene sulfide) polymers using lithium salts. US Patent 5 929 203, assigned to Phillips Petroleum Company (Bartlesville, OK), July 27, 1999. 

The widely investigated Phillips catalyst, which is alkyl free, can be prepared by impregnating a silica-alumina (87 13 composition [101-103] or a silica support with an aqueous solution of Cr03). High surface supports with about 400 to 600 g/m are used [104]. After the water is removed, the powdery catalyst is fluidized and activated by a stream of dry air at temperatures of 400 to 800 °C to remove the bound water. The impregnated catalysts contain 1 to 5wt% chromium oxides. When this catalyst is heated in the presence of carbon monoxide, a more active catalyst is obtained [105]. The Phillips catalyst specifically catalyzes the polymerization of ethene to high-density polyethene. To obtain poly ethene of lower crystallinity, copolymers with known amounts of an a-olefin, usually several percent of 1-butene ean be synthesized. The polymerization can be carried out by a solution, slurry, or gas-phase (vapor phase) process. 

Poly(/ -phenylesulfide), PPS, (white powder, Tg 92 °C, mp 270-290 °C, 65% crystallinity) was the first melt-proccessible polymer to be doped with strong electron acceptors (e.g., ASF5) to yield highly conductive products [90]. The first laboratory synthesis of PPS was reported by Macallum [91] and involved the melt reaction of 1,4-dichlorobenzene, sulfur and sodium carbonate. A commercially product has been available as powder, film or fiber since 1973 from Phillips Petroleum under the trade name Ryton it is produced from 1,4-dichlorobenzene and sodium sulfide (high-pressure process) in a polar solvent (N-methylpyrrolidone) [92]. 

Poly(p-phenylene sulfide), PPS, is produced by the coupling reaction(53) illustrated in Figure I. This process is practiced commerically by Phillips Petroleum Company (X=C1). PPS is a thermally processible, high molecular weight thermoplastic. The discovery of conducting compositions derived from PPS(I3,I4) was... 

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