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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The main difference between polyester-based polyurethane (PU) and polyether-based polyurethane lies in their chemical structure, performance characteristics, and typical applications. Below is a detailed comparison:

1. Chemical Structure
- **Polyester-Based PU**:
  - Made using polyester polyols.
  - Contains ester bonds in its chemical structure.
- **Polyether-Based PU**:
  - Made using polyether polyols.
  - Contains ether bonds in its chemical structure.

2. Properties
**Mechanical Strength:**
- **Polyester-Based PU**:
  - Higher tensile strength and tear resistance.
  - More rigid and durable under mechanical stress.
- **Polyether-Based PU**:
  - Slightly lower mechanical strength compared to polyester PU.
  - Offers good flexibility and elasticity.
**Hydrolytic Stability (Resistance to Water):**
- **Polyester-Based PU**:
  - Poor hydrolysis resistance (prone to degradation in humid or wet conditions).
  - Susceptible to microbial attack.
- **Polyether-Based PU**:
  - Excellent resistance to water and hydrolysis.
  - More suitable for applications involving prolonged exposure to moisture.
**Chemical Resistance:**
- **Polyester-Based PU**:
  - Better resistance to oils, fuels, and solvents.
  - Performs well in chemically aggressive environments.
- **Polyether-Based PU**:
  - Moderate resistance to oils and chemicals.
  - Suitable for environments where chemical exposure is limited.
**Abrasion Resistance:**
- **Polyester-Based PU**:
  - Superior abrasion resistance.
  - Ideal for high-wear applications.
- **Polyether-Based PU**:
  - Slightly lower abrasion resistance.
  - Better suited for applications requiring flexibility.
**Temperature Resistance:**
- **Polyester-Based PU**:
  - Better resistance to high temperatures.
  - Less likely to soften or degrade in heat.
- **Polyether-Based PU**:
  - Performs better at low temperatures (excellent cold flexibility).
  - Can become less stable at higher temperatures.
**UV and Oxidation Resistance:**
- Both types can degrade under prolonged UV exposure unless additives or stabilizers are included.
- Polyether PU generally performs slightly better against oxidation.

3. Longevity
- **Polyester-Based PU**:
  - Shorter lifespan in environments with high moisture or frequent water exposure due to hydrolysis.
  - More durable in dry conditions.
- **Polyether-Based PU**:
  - Longer lifespan in wet, humid, or marine environments.

4. Applications
- **Polyester-Based PU**:
  - Industrial wheels and rollers.
  - Conveyor belts.
  - High-stress seals and gaskets.
  - Automotive parts exposed to oils and fuels.
- **Polyether-Based PU**:
  - Marine and underwater applications.
  - Hydraulic seals and gaskets.
  - Medical devices (e.g., tubing, catheters).
  - Applications requiring flexibility and water resistance.

5. Cost
- **Polyester-Based PU**:
  - Generally less expensive than polyether PU.
  - Economical for dry or chemical-resistant applications.
- **Polyether-Based PU**:
  - Higher initial cost, but potentially lower lifecycle cost in wet environments due to better hydrolytic stability.

6. Summary Table
Property   Polyester-Based PU   Polyether-Based PU      
Mechanical Strength   Higher   Moderate
Water Resistance   Poor   Excellent
Chemical Resistance   Better (oils/solvents)   Moderate
Abrasion Resistance   Superior   Good
Temperature Resistance   Better at high temps   Better at low temps
Flexibility   Moderate   Excellent
UV Resistance   Moderate (with stabilizers)   Slightly Better (with stabilizers)
Cost   Lower   Higher