Ekonol Polyester Resin is one of the first commercial liquid crystalline polymers, a family of materials known for their exceptional stiffness and thermal stability. This polymer was developed in the 1960™s and named after Dr. James Economy, who at the time was head of research at the Carborundum Company. Saint-Gobain acquired the Ekonol business in the mid-1990™s.
This homopolymer is based on p-oxybenzoyl repeat units and is a linear thermoplastic. Ekonol is a highly crystalline polymer but has no observed melting point even at up to 900 - 1000° F. Flow and creep are virtually non-existent below its crystal-crystal transition temperature of 625° F.
Fabrication is accomplished by metallurgical techniques not normally used for polymers; reported mechanical properties of Ekonol were measured on samples, which were compression sintered at 800° F and 10,000 psi. The molded polymer has a flexural strength of 5,500 psi with a modulus of 1x106 psi and a density of 1.44 gm/cc. Ekonol possesses a compressive strength of 15,000 psi and this high strength results in an excellent load bearing capability. The coefficient of thermal expansion of 3.3 x 10-5 in/in/° F is approximately linear from room temperature to 575° F. The absence of aliphatic hydrogen contributes to its excellent thermal stability in air. Ekonol undergoes a maximum weight loss of 3.5% when heated in air from room temperature to 750° F and held for 1 hour at temperature. The maximum recommended continuous service temperature is 500 - 600° F. The maximum recommended intermittent service temperature is 600 - 750° F. Ekonol has excellent solvent resistance with the exception of concentrated sulfuric acid and strong alkalis. The water absorption rate is low at 0.4% after 500 hours at 212° F. Ekonol Polyester is self-lubricating and provides excellent friction and wears properties.
Ekonol Polyester is a very thermally stable polymer, making it easy to blend/fabricate with other high temperature materials. When combined with polytetrafluoroethylene (i.e. PTFE); it produces a composite material that has excellent temperature and wear resistance properties. The Ekonol Polyester/PTFE blend will not wear metal surfaces and resists self-wear better than any other PTFE composition. Applications for Ekonol Polyester/PTFE blends are varied and include packing sets, compressor ring sets, "0" ring seals, spring-loaded seals, lip seals, self-lubricating bearings and rotors or vanes of process pumps. Ekonol Polyester/PTFE works best under environmentally tough conditions where wear resistance, dimensional stability and corrosion resistance are critical.
There are two standard products, Ekonol T101 and M102A, with particle size and apparent density being the key difference. Custom runs for other average particle sizes can be completed upon request.