Study on Preparation, Structure, and Properties of Flexible Shape Memory Epoxy Resin

Abstract:

To improve the toughness of epoxy resins, we add N, N-dimethylformamide (DMF) to epoxy resin as it is curing, and the flexible epoxy resin is prepared. According to the results of Fourier Transform Infrared Spectroscopy (FT-IR), DMF is able to effectively graft onto the epoxy resin. The glass transition temperature (Tg) of the epoxy resin drops from 99.9°C to 19.4°C, indicating a reduction in the thermodynamic stability of DMF/epoxy, according to the results of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). According to tensile studies, DMF/epoxy's mechanical strength is decreased, but its elongation is significantly longer and enhanced by three orders of magnitude. Impact testing reveals a significant improvement in the material's hardness (from 1.67 to 15 J·cm^-2). Furthermore, DMF/epoxy is flexibly bendable. Finally, the DMA test shows that DMF/epoxy can achieve good shape memory at low temperatures to room temperature.

• Periodical: Key Engineering Materials (Volume 999)
• Pages: 75-80
• DOI: https://doi.org/10.4028/p-iwkG1R
• Online since: December 2024
• Authors: Tao Wan*, Shi Cheng Wei, Yu Jiang Wang, Qing Han, Jian She Chen, Bin Chuan Li, Lei Guo, Da Xue Fu, Bo Wang
• Keywords: DMF, Epoxy, Mechanical Properties, Shape Memory Property, Structure

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