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Toughening agents for impact resistance

At Croda our technical experts have developed a range of toughening agents that have been tailor-made to modify different materials to deliver excellent toughening performance in multiple applications.

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Reactive toughening agents for epoxy adhesives

Epoxy structural adhesives are used in a wide range of applications; however, a key limitation of epoxy adhesives is their rigid structure which can cause issues when stress on the system cannot be absorbed, making them brittle. Our novel epoxy functionalised toughening technology, B-Tough A, offers a solution. These products work by inducing phase separation during curing, whilst also being compatible enough to react. The soft, rubbery B-Tough A chains then become grafted into the hard epoxy matrix, improving the impact resistance whilst maintaining the hardness of the adhesive.

Why choose B-Tough A?

Conventional toughening agents for adhesives can have downsides such as being unevenly distributed in the formulation, risk of migration and high viscosity. B-Tough A offers benefits compared to these conventional products such as:

  • Excellent toughening performance for impact resistance due to even distribution in the matrix
  • Improved adhesion after humid ageing due to good thermal and moisture stability
  • Substrate protection from moisture diffusion
  • Easy to formulate with due to lower viscosity, availability in different polarities and high rubber content

Long term protection for epoxy coatings

Epoxy coatings are used in many applications such as for flooring, tank linings, windmill blades, pipelines and marine coatings due to their resilience in tough conditions. However, these coatings can face issues such as cracking under stress and no resistance to high impact, making repairs necessary.

We have specially developed B-Tough C to meet the need to combine flexibility and hardness without negatively affecting other desired properties. These epoxy functional toughening agents, like B-Tough A, are grafted into the hard epoxy matrix. B-Tough C2r is a VOC-free toughening agent suitable for indoor applications. B-Tough C2x is also available for outdoor applications where faster drying is required.

Benefits of B-Tough C

Traditional toughening agents for coatings can have high viscosity, making them difficult to handle. B-Tough C toughening agents for coatings can offer:

  • Improved flexibility whilst maintaining hardness
  • Excellent impact and crack resistance preventing surface marring for optimal protection
  • A liquid product making it easy to formulate with

Improved toughness in biopolymers 

Polylactic acid (PLA) is a biopolymer that has increased in popularity as it is manufactured from renewable resources, making it a more environmentally friendly alternative to petroleum-based polymers. However, PLA is brittle by nature, having low impact and heat resistance which limits the applications that it can be used for.

Modification of the polymer can help to improve its properties and make it suitable for more durable applications. Our Priplast bio-based building blocks provide a great solution as they can be built into the PLA polymer to act as a flexible modifier.

How does Priplast improve performance of PLA?

Modifying PLA with Priplast offers performance benefits such as:

  • Maintaining hardness whilst decreasing brittleness
  • Providing excellent impact strength, even at low temperatures
  • Enhanced hydrophobicity
  • Modification with a renewable building block

Coatings product guide

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B-Tough™ C2r

B-Tough™ C2r

Reactive VOC-free epoxy-functional toughening agent bringing excellent impact strength, combining improved flexibility with hardness for chemical resistant coatings.

B-Tough™ C2x

B-Tough™ C2x

Reactive epoxy-functional toughening agent bringing excellent impact strength, combining improved flexibility with hardness for chemical resistant coatings.

Would you like to know more about the toughening effect?