What's The Difference Between Polyester based PU with Polyether based ?

Polyester based

    Oil/solvent resistance
    Resistance to weak acids/basics
    Abrasion resistance
    Excellent mechanical properties
    Fungus Resistance
    Excellent Vibratory Dampening

Polyester polyurethane is not recommended for use where high humidity or water exposure is a concern. Hydrolysis is a risk which will have a negative effect on the physical properties of the polyurethane.


Polyether based

    Low-temperature flexibility
    Excellent hydrolytic stability
    Food Grade Applications
    Temperature resistance
    Excellent mechanical properties
    Weather (UV) resistance

Polyether polyurethanes are recommended for applications which are expected to experience medium to high stress.


Abrasion Resistance Properties

Without question, the urethanes have outstanding abrasion resistance. They outwear metals, plastics, and other rubbers by a wide margin — often by 8 to 1 or more. Abrasion results from many actions, such as impingement, erosion, impact, scuffing, and sliding.

Sliding refers to scraping and rubbing abrasion. Impingement refers to particles or objects striking the urethane surface at a high angle.

Polyester polyurethane exhibits superior sliding abrasion resistance. This makes it it better suited for applications like scraper blades.
Heat Resistance Properties

Polyurethane elastomers can withstand continuous use up to 194°F (90°C). Flame retardants may be added to the formulation, if required. Both polyester and polyether urethanes perform well at high temperatures. But polyesters are better able to withstand high temperatures longer and are more resistant to heat aging.

Polyethers are less susceptible to dynamic heat build-up.
Low-temperature flexibility

Polyurethane elastomers get harder as temperatures drop. This makes them less flexible and potentially brittle. Depending on the formulation, the brittle point may be between -40°F and -100°F (-40°C and -73°C). Of the two polyurethane types, polyether polyurethane is less affected by cold temperatures.

Polyurethanes can withstand sudden and dramatic temperature drops without cracking. And even at their highest hardness levels, polyurethanes have a better impact resistance than most plastics.
Rebound properties

Some products need to return the energy they absorb (rebound). Polyether polyurethane provides higher rebound than polyester polyurethane.
Shock absorption properties

Sometimes you want the product to absorb the energy it receives (opposite of rebound). In this case, polyester urethane is the better option (e.g. vibration dampening applications).

Hardness Properties

Both polyester polyurethane and polyether polyurethane can be made to any hardness from soft to hard.
Cut and tear resistance

While both polyether and polyester polyurethanes are strong, polyester polyurethanes have a higher tensile strength and a higher cut and tear resistance than polyether polyurethanes.
Water and moisture resistance

Polyether polyurethanes should be selected if the product is to be placed under water or exposed to high humidity as they exhibit excellent hydrolytic stability.

Polyether polyurethanes can be stable in water as warm as 122°F (50°C) for long periods of time. However, they are not recommended for continuous use in water over 158°F (70°C). You can expect .3% to 1% increase in weight due to water absorption and there is a negligible swell in volume.

Polyester polyurethanes are not recommended for applications where water and high humidity is a concern.
Oil and chemical resistance

Polyester polyurethanes are more resistant to exposure to oils, fuels, or chemicals.

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Polyether Urethane vs. Polyester Urethane

 

 

When it comes to polyurethane, there are two main types: polyether urethane and polyester urethane. Although they are both polyurethanes, each has its own unique set of physical properties that are designed for specific applications. Below is a comparison of polyether and polyester polyurethanes showing lists of properties as well as applications for each material.

 

 
Polyester Urethane

 

 

In fact, polyesters are typically famous for their superior sliding abrasion resistance. Moreover, one should make an effort your current fortune bestes live caribbean stud poker casino. This makes them excellent for applications where abrasion subjects the polyurethane surface to high levels of friction, such as with chute liners and scraper blades. Typically, this is the main defining attribute when comparing polyesters with other materials. Polyesters are often called the "workhorse" of high abrasion applications and have gained an excellent reputation when used in highly abrasive environments.

 

 
Properties:

 

 

    Excellent Abrasion Resistance
    Better Shock Absorption
    Higher Tensile Strength
    Good Chemical Resistance
    Withstand Higher Temperatures Longer

 

 
Applications:

 

 

    Scraper blades
    Chute liners
    Hopper liners
    Wear pads
    Snowplow blades
    Screening grids

 

 

 

 

 
Polyether Urethane

 

 

In fact, polyethers are the most common polyurethanes used in the cast elastomer industry. They generally have better dynamic properties than polyesters and are used in wide range of applications such as rollers, bumpers, and bushings. Polyethers tend to make up the majority of polyurethane parts because they are easy to work with and offer more desirable physical properties. Another very interesting thing about polyethers is that they can be tailored with specific additives to perform on the same level or better as polyesters for abrasion resistance. This results in a material that is essentially a hybrid polyether and performs just like a polyester in high scraping abrasion applications.

 

 
Properties:

 

 

    Excellent Dynamic Properties
    Hydrolytic Stability
    Low-Temperature Flexibility
    Good High-Temperature Resistance
    UV Resistance
    Better Rebound

 

 
Applications:

 

 

    Rollers
    High load casters
    Skateboard wheels
    Body Blocks
    Bumpers
    Bushings
    Coil storage pads
    Gears and sprockets
    Pulleys
    Couplings

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