All polyol classes used in polyurethanes have a set of unique attributes that make them useful as the soft-segment in specific polyurethane elastomer applications. Selecting the best polyol for a specific formula can be the difference between making a high-quality product or one that's low-performing. The key for proper material selection is a good understanding of the inherent characteristics of each polyol chemistry.
What are the polyester-polyol options that exit in selecting the best polyol for a specific polyurethane application?
CASE (Coatings, Adhesives, Sealants, and Elastomers), foam and elastic fiber applications all utilize a diverse family of polyester polyols that includes:
Aliphatic based polyester polyols
Aromatic polyester polyols
Polycaprolactone polyols
Polycarbonate polyols
The selection criteria includes economics and the performance attributes required in the polyurethane elastomer. Polyester based urethane parts, for example, are used for their strength properties and toughness, durability, performance at higher temperatures and retention of properties under adverse chemical and environmental exposures.
What are the key attributes of polyurethanes based on polyester polyols?
Compared to polyether polyols in polyurethane elastomers, polyesters offer higher physical properties, cut, tear and wear resistance, better sliding abrasion and flex fatigue resistance. They are tough and durable.
Polyester polyols in a polyurethane also exhibit very good resistance to oil, grease, fuels and nonpolar solvents.
The polyester backbone displays good thermo-oxidative stability which makes them better suited for high-temperature application.
Polyester based urethane elastomers show good adhesion to commonly used substrates.
Vibration dampening and shock absorption properties
The inherent properties of polyester polyols make them an excellent choice for the following industries and applications for polyurethane elastomers:
Oil field and mining applications: screens, conveyor belt scraper blades
Wheels, industrial and printing rolls
Pipeline pigs
Adhesives
Footwear and shoe soles
Industrial applications requiring good thermal stability.
Food contact (FDA compliant)
TPUs for automotive and cable jacketing
Rigid and spray foam for the aromatic polyester polyols.