Available from Phillips in commercial quantities.

Sulfolane is a highly stable polar compound with excellent properties and unusual thermal and chemical stability. This solvent is preferred for extractions of benzene, toluene and xylene from oil refinery streams, and for removal of acid gas constituents from various gas streams.

Sulfolene is a chemical intermediate.

Whichever you need, Phillips can satisfy your cyclic sulfone requirements—right now—with immediate shipments in drums, tank trucks, tank cars.

Special Products Division PHILLIPS PETROLEUM COMPANY. Bartlesville. Oklahoma 74004

For information, phone: 918 661-5556 For orders, phone: 806 274-5236

At Phillips 66 it's performance that counts"

CIRCLE 8 O N READER SERVICE CARD

16 C & E N August 6, 1 9 7 3

New polymers boast high thermal stability A new monomer and a new polymeriza­tion technology that produce organic polymers with very high thermal stabil­ity have been developed by Horizons Research, Inc., Cleveland. The mono­mer is 2,3,5,6-tetraaminopyridine tri-hydrochloride (TAP-3HC1) and is ob­tained in high yield and high purity as the stable salt. Unlike conventional aromatic tetraamines, TAP-3HC1 reacts as a difunctional monomer with diacid halides or dianhydrides at the 3,5 sites.

Polymerization using TAP-3HC1 is carried out in aprotic solvents, such as /V-methylpyrrolidinone, under mild conditions. These reactions are simple and form completely gel-free pre-cyclized polyamides.

The polyamides derived from TAP-3HC1 and either isophthaloyl chloride

Gerber: cyclized structures

or 1,4,5,8-naphthalenetetracarboxylic dianhydride are the first soluble, mono­mer-free, precyclized polymers that yield stable polybenzimidazole (PBI) and polyimidazopyrrolone on heating.

The superior stability of TAP-derived polymers is attributed by their discover­er, Dr. Arthur H. Gerber of Horizons Research, to their more perfectly cy­clized structures. They also have only one vulnerable C—H bond in each residual TAP nucleus of the cyclized polymer. Polymers prepared from con­ventional tetraamines have at least two such bonds.

Other advantages of the new polymer technology, according to Dr. Gerber, include the formation of PBI by elimina­tion of water rather than phenol, which lowers the amounts of volatile com­ponents present. Gelation problems, encountered with conventional tetra­amines, are also eliminated. Stable polymers are produced from TAP-3HC1 without requiring polycondensation in polyphosphoric acid.

TAP is prepared in a simple, three-step sequence from pyridine. The first step is amination of the pyridine. This is followed by nitration to produce 2,6-diamino-3,5-dinitropyridine, and subse­quent catalytic reduction to 2,3,5,6-tetraaminopyridine or its salts. The catalysts are platinum or palladium, usually supported on charcoal or barium sulfate.

The bis-o-diamines, of which TAP is one example, produce polymers having important applications in space technology, such as radiation and ther­mal insulation. They also are used in making films and fibers with good physical properties required in protec­tive coatings, laminates, adhesives, and composites.

Breeder reactor project progressing The project to build a liquid-metal fast-breeder reactor (LMFBR) demonstra­tion plant in the U.S. is moving ahead cautiously. Initial contracts were signed late last month following court deci­sions favorable to that step in the proj­ect.

Involved in signing the basic contract were the Atomic Energy Commission, Project Management Corp. (PMC), Breeder Reactor Corp. (BRC), and the Tennessee Valley Authority. PMC is the company created to provide overall management and coordination for de­sign, construction, and operation of the demonstration plant. BRC was formed to represent utilities contributing to the project. AEC has a main responsibility for the nuclear steam supply system for the plant. And TVA is responsible for plant operation and maintenance. The plant site is on the Clinch River in Oak Ridge, Tenn.

With signing of the basic contract, PMC now can proceed with negotiation of other contracts. Late last year, pro­posals by Westinghouse as prime re­actor manufacturer and by Burns and Roe and Holmes and Narver, Inc., as architect-engineers were selected as the basis for negotiations of final contracts for the work. General Electric and Atomics International are also involved in the project.

The basic contract was signed after the U.S. district court denied a request to enjoin execution of the breeder con­tracts, and the decision was upheld by the court of appeals. As part of a re­sponse to an earlier June appeals court ruling that the National Environmental Policy Act requires preparation of an environmental impact statement cover­ing the total breeder reactor program, AEC had made a determination that contracts could be signed and imple­mented without having a significant ad­verse impact on the environment during the period required for completing the full environmental review.

Among its conclusions, AEC noted that any limited impact from contract implementation would be readily redressable should it be required by the overall review. APX also said that adoption of project alternatives, in­cluding cessation of the project itself, would not be foreclosed by the con­tracts, nor would expenditures be so large as to affect eventual decisions following the environmental review.