What Is The Different Between PTMEG And PCL?

PTMEG are known as high-performance polyols capable of formulating polyurethane elastomers in several positive directions. PTMEG polyols afford polyurethane elastomers with enhanced performance with respect to flexibility, dynamic properties, low-temperature performance, resiliency/rebound, hydrolytic stability, low hysteresis, and abrasion resistance.

Polycaprolactone polyols represent a special class of aliphatic polyester polyols used in high-performance polyurethane elastomers. Polycaprolactone-based polyurethanes incorporate many of the benefits assigned to PTMEG polyols, such as good hydrolytic stability in wet environments, low-temperature flexibility, excellent toughness and abrasion resistance, excellent flex fatigue life, durability, and good elastic memory. In addition, polycaprolactone-based PURs are tougher materials than PTMEG-based PURs and exhibit higher temperature properties and better solvent resistance.

Hydrolytic stability of the PTMEG polyether structure is superior to the ester linkage; however, when immersed in water, the polyethers absorb water and are plasticized, losing mechanical properties. In water immersion applications at lower temperatures, the polycaprolactone polyols are preferred, furthered by their overall significantly higher tensile properties. Chemical resistance relates to oils, fuels, and hydrocarbon solvents. There are two types of abrasion resistance are sliding and impingement. Sliding refers to scraping and rubbing abrasion while impingement refers to particles striking the urethane surface. Polycaprolactone-based polyurethanes display higher tensile and tear resistance and exhibit excellent sliding abrasion resistance. This dynamic makes them ideal for applications like belt scraper blades and chute liners. PTMEG, due to its's higher resiliency, offers better performance in applications where impingement abrasion is the dominant form of wear. This dynamic makes PTMEG based polyurethanes the choice for sandblast curtains and slurry pipe liners. Processing characteristics of polycaprolactone based urethanes are excellent, derived from the low polydispersity of the polycaprolactone polyols and the lower viscosities of the attendant prepolymers and TPUs.