Epoxy resin monomers with reduced skin sensitizing potency

Area of Science:

• Polymer Chemistry
• Toxicology
• Materials Science

Background:

• Epoxy resin monomers (ERMs), such as diglycidyl ethers of bisphenol A and F (DGEBA and DGEBF), are widely used in thermosetting polymers.
• These common ERMs are known skin sensitizers, frequently causing allergic contact dermatitis, particularly in occupational environments.

Purpose of the Study:

• To design and synthesize alternative ERMs with reduced skin sensitizing potency.
• To evaluate the efficacy of these alternative ERMs in forming thermosetting polymers with comparable technical applicability and thermal stability.

Main Methods:

• Design and synthesis of novel epoxy resin monomers.
• Assessment of sensitizing potency using the in vivo murine local lymph node assay (LLNA).
• Evaluation of polymer technical applicability and thermal stability via thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC).

Main Results:

• All six synthesized alternative ERMs exhibited decreased sensitizing potencies compared to DGEBA and DGEBF.
• The most effective alternative monomer showed an LLNA EC3 value approximately 2.5 times higher than DGEBA and DGEBF.
• Four of the six alternative ERMs yielded polymers with thermal stability comparable to those derived from DGEBA and DGEBF.

Conclusions:

• The development of improved ERMs with reduced skin sensitization is a viable strategy to mitigate contact allergies.
• These alternative ERMs offer a direct approach to reduce the incidence of allergic contact dermatitis in epoxy resin users, especially in occupational settings.
• The synthesized monomers successfully balance reduced allergenicity with the necessary properties for thermosetting polymer applications.