Polyols are the foundation of polyurethane performance. The choice of polyol chemistry has a significant impact on processing, mechanical properties, durability, chemical resistance, environmental stability, and overall application performance. Each polyol family offers a unique balance of characteristics, making it better suited for specific end-use requirements.
The comparison below highlights the typical performance trends of the major polyurethane polyol families. While these comparisons provide a useful starting point for material selection, actual performance depends on factors such as molecular weight, functionality, formulation, processing conditions, and application requirements. Gantrade's technical and commercial teams are available to help identify the most suitable and cost-effective polyol solution for your application.
| Feature | PTMEG | Polyester Polyols | Polycaprolactone Polyols | Polycarbonate Polyols | PO3G (Bio-Based) Polyols |
| Hydrolysis Resistance | Excellent | Poor (unless modified) | Very Good | Excellent | Excellent |
| Ether backbone is stable to water attack | Ester linkages are susceptible to hydrolytic cleavage | Semi-crystalline domains slow hydrolytic attack | Carbonate linkages resist hydrolysis and oxidation | Polyether structure similar to PTMEG | |
| Oil / Solvent Resistance | Fair | Excellent | Excellent | Excellent | Fair |
| Ether segments are more compatible with hydrocarbons | Polar ester groups resist swelling in oils | Crystalline ester segments limit solvent diffusion | High polarity and tight structure resist swelling | Polyether backbone allows some hydrocarbon swelling | |
|
Dynamic Heat Build-Up |
Very Low | High | Low | Low | Very Low |
| High resilience and low hysteresis polyether segments | Ester segments generate higher hysteresis under load | Crystalline domains reduce energy dissipation | Strong carbonate backbone minimizes internal friction | Highly elastic polyether structure | |
| Application Examples | High Speed Wheels | Printing Rollers, Seals | Rollers, Seals | Severe Service Coatings and Parts | Green Performance |
| Low heat buildup and high rebound ideal for dynamic loads | Oil resistance and hardness retention | Severe Service Seals Excellent compression set and durability | Excellent compression set and durability | Bio-based alternative with PTMEG-like properties | |
| Abrasion Resistance | Excellent | Very Good | Very Good | Excellent | Excellent |
| Elastic polyether segments resist crack propagation | Higher hardness from ester segments improves wear | Crystalline structure improves surface durability | Strong carbonate backbone resists mechanical wear | High resilience reduces surface fatigue | |
| Cut Resistance | Very Good | Good | Very Good | Excellent | Very Good |
| Elastic structure distributes stress and prevents crack propagation | Higher stiffness but lower toughness allows cuts to initiate | Crystalline reinforcement improves resistance to sharp edges | High toughness and cohesive strength resist cutting forces | Elastic polyether network resists crack propagation | |
| Impact Resistance | Excellent | Good | Very Good | Excellent | Excellent |
| Very high resilience absorbs sudden loads | More rigid ester segments dissipate energy through deformation | Semi-crystalline structure balances stiffness and toughness | Strong backbone with high toughness absorbs impact energy | Elastic structure similar to PTMEG provides strong rebound | |
| Tensile Strength Potential | High | High | High | Very High | High |
| Good phase separation creates strong hard-segment domains | Polar ester groups increase intermolecular attraction | Crystallinity contributes to reinforcement | Strong carbonate backbone increases cohesive strength | Elastic polyether segments support high elongation | |
| Tear Strength Potential | Excellent | Good | Very Good | Excellent | Excellent |
| Elastic network distributes stress effectively | Higher stiffness can initiate tear propagation | Crystalline reinforcement resists tearing | High toughness from carbonate backbone | High elasticity prevents crack growth | |
Compression Set |
Excellent | Fair | Excellent | Excellent | Excellent |
| Elastic ether backbone recovers after deformation | Ester segments exhibit more permanent deformation | Crystalline domains help shape recovery | Strong backbone maintains dimensional stability | High resilience polyether structure | |
| Load Bearing Capacity | Excellent | Very Good | Very Good | Excellent | Excellent |
| Strong elastomer network with good fatigue resistance | Higher modulus from ester segments supports static loads | Crystalline reinforcement improves compressive strength | High mechanical strength and dimensional stability | Elastic network supports cyclic loads effectively | |
| Low Temperature Flexibility | Excellent | Fair | Good | Good | Excellent |
| Very low Tg polyether segments | Higher Tg due to ester polarity | Moderately low Tg with partial crystallinity | Higher Tg than polyethers but still flexible | Very low Tg similar to PTMEG | |
| Glass Transition (Tg) | Very Low | Moderate | Low | Moderate | Very Low |
| Flexible ether backbone reduces chain stiffness | Polar ester groups restrict chain mobility | Flexible segments with crystalline reinforcement | Rigid carbonate linkages increase Tg | Polyether backbone with flexible C-O bonds | |
| Crystallinity | Moderate | Low | High | Low | Moderate |
| Regular ether structure allows partial crystallization | Irregular ester structures disrupt crystallinity | Caprolactone segments crystallize easily | Bulky carbonate groups hinder crystallization | Regular repeating ether units allow ordering | |
| Rebound / Resilience | Very High | Moderate | Moderate | Moderate | Very High |
| Low hysteresis polyether network | Ester segments dissipate more energy | Crystallinity increases energy loss during deformation | Rigid backbone reduces elastic recovery | Elastic polyether similar to PTMEG | |
| UV / Oxidative Stability | Good | Fair | Good | Excellent | Good |
| Ether backbone relatively stable to oxidation | Ester groups more prone to oxidative degradation | Stable aliphatic structure | Carbonate groups resist oxidation and UV degradation | Polyether backbone similar to PTMEG | |
| Microbial Resistance | Excellent | Poor | Good | Excellent | Excellent |
| Ether backbone not easily metabolized by microbes | Ester linkages susceptible to microbial enzymes | Semi-crystalline structure slows microbial attack | Carbonate backbone highly resistant to biodegradation | Polyether structure resists microbial attack | |
| Processing Reactivity | Fast | Slowest | Slower | Slower | Moderate |
| Primary OH; Highly flexible backbone |
Primary OH; ester backbone Acid numbers can decrease the reactivity; highest acid values of the 5 groups |
Primary OH; semicrystalline backbone | Primary OH; slower processing arises from polymer-chain mobility and intermolecular interactions | Primary OH ; processing similar to PTMEG, typically slightly slower |
Need help selecting the right polyol? Contact Gantrade's technical and commercial team for expert guidance on choosing the optimal polyol chemistry for your application. We'll help you evaluate performance requirements, explore alternative chemistries, and identify the most cost-effective solution based on current market conditions and product availability.
