TERRIN™ polyols are 100% aliphatic polyester polyols containing a minimum of 50% recycled content. (1) These aliphatic polyester polyols, now fully commercial globally, offer formulators the opportunity to explore the benefits of aliphatic ester polyols at competitive polyether pricing and may align with raw material sustainability and cost reduction strategies. TERRIN™ 168G contains a minimum 10% renewable materials and TERRIN™ 170 is 100% either recycled or renewable.(1) TERRIN™ polyols are prepared from glycols, including diethylene glycol and bio-based renewable glycerol, and a mixture of recycled carboxylic acid-functional monomers comprising mainly adipic acid and 6-hydroxycaproic acid (functionally equivalent to caprolactone). Due to their unique structures, TERRIN™ polyols are liquids at 20°C and remain fluid at -15°C / 5 °F and below.(2) They do not crystallize when cooled, but exhibit Tg in the range -60 to -75°C. They can be used in lieu of or in combination with conventional polyether or polyester polyols to formulate a variety of polyurethane products. The resulting polyurethanes can be formulated to be soft and flexible or hard and stiff. An overview of TERRIN™ polyols is available on TERRIN.invista.com.
Lab tests of TERRIN™ polyols in viscoelastic (VE) and high-resilience (HR) foams made using model foam formulations suggest that TERRIN™ polyols can be considered as partial near-drop-in replacements for polyols commonly used in VE foams and that TERRIN™ 170 can be considered as a partial substitute for conventional polyols in HR foam.
For VE foams, these lab scale tests have shown:
- Little or no adjustment to the catalyst package was required to maintain reactivity similar to the reference systems using conventional polyols.
- Wet and dry compression set, elongation at break, and hysteresis loss were similar to the reference foams in all cases.
- Some minimal reformulation may be needed to match specific properties of the reference system, e.g. small changes in isocyanate index.
Depending on choice of TERRIN™ polyol and substitution level, differentiated properties may be obtained compared to reference formulations. Possibilities include faster recovery time, higher tensile strength, and higher CFD. Testing also suggests possible slower burn rate, but further burn testing is warranted due to the complex nature of burn testing.
For HR foams, benefits seen in these lab-scale tests include:
- Increased strength and load-bearing capability
- Potential to substitute for or use in combination with graft polyols
- Potential to reduce cost
- Renewable and recycled content (1)
- Similar reactivity to conventional polyols
It should be noted that the model foam formulations tested were not optimized to achieve any particular set of performance characteristics and it may not be possible to simultaneously achieve all of the potential benefits listed above. These results are only intended to provide the formulator with comparative trends that may help in selection and use of TERRIN™ polyols for VE or HR foams.
The author, Richard P Beatty, is a Technical Fellow with INVISTA with over 30 years’ experience in the specialty chemicals industry. For further information, please contact INVISTA at 1-800-231-0998 or terrin@INVISTA.com.
1 As defined by ISO 14021 section 7.8; preliminary estimate based on small-scale production.
2 Patents pending; consult the SDS for additional physical-chemical, safety and health information.