Microporous-micronucleus composite structure endowing heterogenous polyamide 6 with low-temperature toughness, low dielectric constant, fire retardancy and antibacterial activity

Utilizing the difference in compatibility and phase transition among PA6, monoglyceride (MG), octaphenylsilsesquioxane (OPS) and zinc diethylphosphinate (ZDP), a PA6 composite with microporous-micronucleus structure is simulated and designed. Due to the passivation micro-cracks effect of microporous-micronucleus structure, the MG/OPS/ZDP/PA6 composite exhibits excellent low-temperature impact strength (5.58 kJ m⁻², 203.3% higher than neat PA6 at −170 °C). The nano-gap and nano-cage OPS endows the MG/OPS/ZDP/PA6 with low dielectric constant (2.95 at 100 Hz). The thermal insulation effect of micropores and the synergistic effect of OPS and ZDP in the micronucleus lead to the high flame retardancy of MG/OPS/ZDP/PA6. Meanwhile, the MG on the inner surface of the micropore and the ZDP in the micronucleus endow a dual antibacterial activity. This work provides a guideline for the construction of microporous-micronucleus structure to realize the functional design of composite.