High-performance Bio-based Polyols for High-end Applications

TAGS:  Sustainability / Natural Adhesives     Polyurethane Adhesives    

This is a sponsored article by Cargill.

The manufacturing, construction, and engineering industries rely heavily on polyols and their derivatives to improve the performance and properties of adhesives, sealants, and coatings for diverse applications.

Polyols are also built into diverse polyurethane polymers through different combinations with isocyanate. Polyurethane polymers are then used across the industrial sector for different applications. 

The different formulations of polyols ensure users can take advantage of products with specialized properties that meet specific use cases. For example:

• The adhesives and coatings manufacturers can integrate properties such as increased longevity, extensive tensile strength, and dust resistance in products by using the proper formulation.
• In engineering and construction, properties such as durability, thermal, chemical, and corrosion resistance can be achieved through the correct combination.

Different polyols work within different formulations. Adopting a one-size-fits-all approach to formulating polyols leads to the creation of low-performance products. Hence, ensuring the formulation is right to meet a specified application is the first step to developing and utilizing high-performance polyols.

Let’s explore the properties and industrial applications of Cargill's bio-based Priplast™ polyester polyols and Pripol™ dimer fatty acid and diol grades with a focus on how they ensure sustainability benefits.

Leveraging High-performance Polyols for Polyurethane Adhesives

Generally, high-performance adhesives ensure proper dispersion, distribution, and compatibility on application. The other properties, such as corrosion resistance or increased flexibility that adhesives provide, are determined by their chemical formulation. For polyurethane adhesives, formulated through combinations of polyols and isocyanate, added properties include:

• durability,
• adhesion to an extensive range of substrates, and
• chemical resistance.

Cargill's Priplast™ polyols and Pripol™ dimer diol assure high-performance formulations with their dimer technology that integrates polyols and other flexible elements into polyurethane. The incorporation of dimer technologies results in a diverse range of Priplast™ polyester polyols such as Priplast™ 3192, Priplast™ 1838, Priplast™ 3238, and Priplast™ 3294. The chemical structure of Priplast™ polyester polyol is shown in Figure 1 below.


Figure 1: Chemical Structure of Priplast™ Polyester Polyol

Properties of Polyester Polyols

The properties of polyester polyols may differ according to the formulation of each product. Hence, the diverse range of Priplast™ polyester polyols products will be used as a basis here. Polyurethane adhesives that are based on polyester polyols come with distinct characteristics that differ from other popular options such as polyether polyols. These characteristics include:

1. Improved physical properties such as higher resistance to wear and tear from physical contact or constant use of surfaces that incorporate polyester polyols. Other physical properties include durability, flex fatigue resistance, and increased resistance to sliding abrasions.


2. Excellent resistance to water, alkaline and acidic components, and a diverse range of polar solvents. Increased resistance to chemicals and oils makes polyol-based polyurethane adhesives suitable for application on surfaces in hazardous environments.


3. Increased thermo-oxidative stability makes the polyols suitable for use within high-temperature applications and environments.


4. The durability and flex resistance of polyester polyols also serves as vibration-dampening and shock-absorption materials to protect surfaces.


5. Most Priplast™ polyester polyols have FDA clearances** for food contact materials. As such, they are excellent options for developing polyurethane items that may come in contact with food or are used in the food and beverages industry.
   **FDA clearances per 175.105 (adhesive) and 175.300 (coatings). Contact Cargill for food contact status.

Figure 2 below illustrates the hydrophobicity of polyester polyols against water for PU.


Figure 2: Moisture Uptake at 23°C (%), Elastomer Formulation

Industrial Applications of Priplast™ Polyols in Polyurethane Adhesives

The properties of Priplast™ polyester polyols make them excellent choices for a diverse range of industries. These industries include oil & gas, automotive, coatings, painting, food & beverages, 3D printing, and footwear manufacturing. Focusing on the application of polyol-based polyurethane as adhesives, sample use cases include:

1. Adhesive and coatings for screens, corrosion resistance agents, and to ensure thermal stability within surfaces of heavy equipment in the mining and oil & gas sectors.
2. Adhesives and corrosion preventive agents for pipes, cables, window seals, and surfaces within the construction sector.
3. Protective coatings for cable jacketing within the automotive industrial sector. 
4. Pripol™ diols and Priplast™ polyester polyols are very hydrophobic. This means they absorb far less moisture compared to other polyols and generate much less CO₂ bubbles when cured with isocyanates.
5. These products contain up to 100% bio-based* carbon content making them a sustainable ingredient.

Discover Product Guide to Formulate Smarter Adhesives and Sealants by Cargill »

Leveraging Pripol™ Grades in Flexible and Hot-melt Adhesives

Pripol™ dimer fatty acids and dimer diols are used as monomers in polyamide and polyester hotmelt adhesives to bring flexibility, water barrier properties, and improved adhesion to a broad range of substrates, including plastics and metal. Pripol™ range consists of a diverse range of monomers that bring better durability to adhesives. Examples of these monomers include Pripol™ 1006, Pripol™ 1013, Pripol™ 1009, and Pripol™ 1010 VEG.

Pripol™ grade properties and characteristics include:

1. Pripol™ dimer fatty acids and diols bring about excellent resistance to heat, abrasion, wear and tear, moisture, and other atmospheric corrosive agents in a variety of polymers. These add to the durability of adhesives for a diverse range of industrial applications.


2. Pripol™ dimer fatty acids are durable and exhibit excellent flexibility characteristics. This makes the Pripol™ range highly resistant to fatigue, wear, and moisture.


3. Pripol™ range incorporates flexibility and reduces the possibility of shrinkage and wearing-down when used in adhesives.


4. Pripol™ enhances adhesion to low polar substrates.

Industrial Application of Pripol™ Diols and Dimer Fatty Acids

The characteristics of the Pripol™ range improve the capabilities of adhesives and widens its application to include its use in sectors such as the building and construction foam market, mining, oil & gas, and automotive industries. Its industrial applications include:

• In the construction and building foam market – it prevents water permeation dissipates heat when used to protect insulation and building installations.
• Its high-performing adhesive properties make it applicable to a broad range of substrates including metal, plastic, concrete, and wood.
• Its resistance to water, alkaline and acidic components, and moisture, and a wide range of polar solvents make it an excellent system to protect external installations from environmental conditions.

Enabling Environmental Sustainability with Bio-based Polyols

Environmental sustainability is an important consideration in today's world, and finding alternatives to conventional materials has become a key aspect of promoting sustainability. The use of Cargill bio-based* polyols offers several benefits such as:

• reducing carbon footprint,
• utilization of natural resources, and
• minimizing waste (through improving longevity of bonded articles and installations) along with high-performance.

Cargill polyols are used for various industrial applications along with high-performing benefits to polyurethane, polyamides and polyester adhesives and resins.

Innovation in Adhesives with Priplast™ Polyester Polyols and Pripol™ Range

Priplast™ polyester polyols and Pripol™ diols are innovative derivatives for developing polyurethane adhesives and sealants for the industrial sector. These high-performing materials are bio-based* solutions that can be combined with other materials to improve the physical properties and characteristics of adhesives. 

The wide range of polyols offered by Cargill includes:

1. Priplast™ 3192 – A semi-crystalline polyester polyol with excellent dispersion capabilities suitable for developing polyurethane adhesives for a broad range of industries.


2. Priplast™ 1838 – A versatile, amorphous, polyester polyol developed for improving the durability, flexibility, corrosion, and thermal-resistant profile of adhesives.


3. Priplast™ 3238 – A 100% bio-based* polyester polyol that supports the development of more sustainable polyurethane systems.


4. Priplast™ 3294 – A semi-crystallite, 100% bio-based* polyester polyol that exhibits excellent durability and resistance to water.


5. Pripol™ 2033 – A fully amorphous, hydrophobic, 100% bio-based* dimer diol as diol components to enhance water barrier properties.


6. Pripol™ 2043 – A fully amorphous, non-crystalline dimer diol with increased functionality and excellent chemical resistance.


7. Pripol™ 1006 – A high difunctional, distilled, hydrogenated, and 100% bio-based* dimer acid that enables the development of adhesives with excellent durability, moisture, and thermal-resistance capabilities.


8. Pripol™ 1013 – A high difunctional, non-hydrogenated, and 100% bio-based* dimer acid that enables the development of adhesives with excellent durability, and moisture-resistance capabilities.

Disclaimer: *Cargill bio-based carbon content calculated according to ASTM D6866 and EN 16640.