POLYMEG® polyols are polytetramethylene ether glycols (PTMEG) produced by polymerizing tetrahydrofuran. POLYMEG polyols are linear diols with a backbone of repeating tetramethylene units connected by ether linkages. The chains are capped with primary hydroxyl units.
Benefits and Applications
The primary applications for POLYMEG polyols are as the soft segment of polyurethanes, copolymer polyesters and polyamide elastomers. As a component of urethane elastomers, the polyols are used in the following systems:
- Thermoplastics for injection molding and extrusion
- Thermoset polyurethanes, castable prepolymers, millable gums
- Metal and textile coatings/linings and adhesives
- Spandex elastic fibers
High performance elastomers made with POLYMEG polyols are used in a large number of applications, including:
- Automotive
- Adhesives and sealants
- Coatings
- Engineered components
- Industrial
- Sports equipment
- Clothing
Toxicology/Regulatory
Polytetramethylene ether glycols are not hazardous as defined by the OSHA Hazard Communication Standard. Polytetramethylene ether glycols are a waxy solid at room temperature, but are heated to 40º C/104º F prior to loading so that they can be transported and delivered as a liquid. The molten polymer may cause thermal burns and can cause serious burns to the eyes. Polytetramethylene ether glycols can be mildly irritating to the skin but are not considered a skin sensitizer. Contact with the eye can cause irritation, and they are not expected to be an inhalation hazard. Polytetramethylene ether glycols are not expected to be an ingestion hazard. There are no known chronic health effects associated with long term exposure to polytetramethylene ether glycols.
The polytetramethylene ether glycols are not regulated by the Department of Transportation (DOT). They are not subject to EPCRA §313 Toxic Release Inventory reporting, Clean Air Act §112 (Hazardous Air Pollutants) or SARA Title 311/312 reporting. The polytetramethylene ether glycols are not included in the various EPA Resource Conservation and Recovery Act, and Clean Water Act lists, nor are they on the California Proposition 65 lists. The polytetramethylene ether glycols are not subject to state right to know reporting requirements.
The polytetramethylene ether glycols are considered polymers, and therefore are included or exempt from the U.S. TSCA Inventory, the European EINECS, the Korean ECL, the Japanese ENCS, the Philippines PICCS, the China IECS, the Canadian DSL and the Australian AICS.
Storage and Handling
POLYMEG polyols are shipped in 55-gallon (208L) closed-head steel drums, coiled and insulated tank cars, and tank trucks. All shipping containers undergo a rigorous inspection in accordance with the standard procedure used for shipping product for food applications. The product is loaded and bulk shipped at a minimum 65º C (150º F). Normal precautions should be maintained in handling hot liquids during the unloading of bulk shipping containers and warmed drums.
POLYMEG polyols are stabilized to prevent degradation in storage and during normal handling. Prolonged heating under a nitrogen blanket 50-65º C (125-150º F) is recommended. However, the presence of air will result in partial oxidation and degradation. The first indication of improper heating is an increase in APHA color, followed by a moderate increase in both peroxide content and acid number. Thermal decomposition will occur under anaerobic conditions at 210-220º C (410-430º F) with tetrahydrofuran as the major decomposition product.
When stored in tanks, POLYMEG polyols must be blanketed with dry nitrogen to prevent moisture pickup and possible discoloration in the final polymer product. Storage tanks should provide for adequate circulation of the contents and be equipped with proper instrumentation to control the storage temperature—generally at 55-65º C (130-150º F). Low-pressure steam and/or electric coils should be used as the heat source for the tank contents and heat tracing of pipelines.
POLYMEG polyols are completely stable for at least one year when stored under a nitrogen atmosphere at a maximum temperature of 55º C (130º F). At a temperature of 100º C (212º F), stability is limited to a few days.
POLYMEG polyols are hygroscopic and can absorb as much as 2% moisture in an unprotected environment. Gross amounts of water are removed by azeotropic distillation with toluene. Further reduction in water content can be achieved by heating for several hours at 120-150º C (248-302º F) under reduced pressure (less than 20mm Hg). The apparatus must be cleaned and free of air, oxides and acids to minimize contamination and oxidation.
Drums may be warmed up to about 70º C (160º F) for about 24-hours to melt the contents. Thereafter, storage at 38º C (100º F) will prevent re-solidification. Open drums with partially used contents should be blanketed with nitrogen. If partial solidification occurs, it is recommended that the material be re-melted to prevent stratification and to facilitate handling.
Alternative methods to melt drum contents:
- Steam chest with free steam at 100º C (212º F) for 9-16 hours.
- Plate coil drum heater using low-pressure steam in coils to heat until the drum skin temperature is about 95º C (200º F).
- Mantle drum heaters using a thermostat to ensure that the drum skin temperature does not exceed 95º C (200º F).
- Band drum heaters placed on lower part of the drum. Control with thermostat to ensure that the drum temperature does not 95º C (200º F).
- Place a tarp over a series of drums. Free steam under the tarp will melt the drums overnight.
More detailed safety and disposal information about this product is contained in the material safety data sheet (MSDS). All users of our products are urged to retain and use the MSDS. A MSDS is automatically distributed upon purchase/order execution.