At the mechanistic level, the epoxy groups in ELO can both increase the free volume fraction of the polymer as softening segments, thereby reducing the glass transition temperature and improving flexibility, impact resistance, and low-temperature toughness; and react with the released HCl during PVC thermal dehydrochlorination through addition or scavenging reactions, inhibiting the formation of conjugated polyene structures and delaying thermal discoloration and performance degradation. Therefore, ELO is often used as a secondary plasticizer and co-stabilizer, exhibiting a significant synergistic effect with lead-free stabilization systems such as Ca/Zn and Ba/Zn, and possesses advantages such as low volatility, low migration, and low odor.
In terms of applications, ELO is widely used in PVC films, artificial leather, flooring materials, cable compounds, and hoses, at a dosage of 5–20 phr to improve processing rheology and long-term heat stability. In coatings and inks, ELO can be used as a reactive diluent or flexible modifier to enhance crosslinking density and adhesion. In epoxy resin, sealant, and adhesive systems, ELO achieves a balance between toughness and chemical resistance through its multi-functionality, and increases renewable content. In addition, in rubber and elastomer formulations, ELO helps to improve dynamic mechanical properties and weather resistance.
Compared to epoxidized soybean oil (ESO), ELO has a higher theoretical epoxy value due to the higher unsaturation of the base oil, and typically exhibits stronger HCl scavenging and plasticizing effects under the same dosage conditions. However, it is more prone to discoloration under high-temperature and light exposure, requiring the use of antioxidant and light stabilization systems such as hindered phenols, hindered amines, or UV absorbers. The limitations of ELO also include: compatibility boundaries at very high filler loadings, challenges in color control, and cost fluctuations affected by the seasonality of crops.
Overall, epoxidized linseed oil, with its renewable source, phthalate replacement potential, and regulatory friendliness (e.g., REACH compliance), has become a key raw material for sustainable plasticization and stabilization. With the advancement of green epoxidation processes and functionalization routes, the application prospects of ELO in high-performance PVC, low-VOC coatings, and bio-based composite materials will continue to expand.