Preparation and properties of flame retardant biobased polyamide elastomer with shape memory

Abstract

AbstractNylon is the general name of high molecular polymers with amide bonds repeat structure in the main chain. Because of its good wear resistance, excellent chemical resistance and outstanding impact resistance, it is widely used in various fields of national life, such as automobile parts, oil pipelines, electronic parts, gears, connectors, coating materials and medical applications. Using isocyanate terminated polyamide prepolymer as hard segment, polypropylene glycol as soft segment and triethanolamine as crosslinking agent, polyamide elastomer was flame retardant modified by adding reactive P flame retardant and P/N synergistic flame retardant mechanism. The sample was named IAHDP‐x, in which IAHD is the synthetic hexamethylene diamine polyaitaconic acid, and x is the mass of the added flame retardant DDP. Its tensile properties, fatigue resistance, self‐recovery and tear resistance were investigated. The results revealed that the synthesized phosphorus flame retardant (9,10‐dihydro‐9‐oxa‐10‐[N,N‐bis‐(2‐hydroxyethylamino methylene)]‐10‐phenanthroline‐10‐oxide (DDP)) could not only enhance the flame retardancy, but also strengthen the mechanical properties of polyamide. Among them, the LOI and UL‐94 of IAHDP‐1.2 were 27.6% and V‐0, respectively, indicating that it could be used as flame retardant material; Cyclic tensile test demonstrated that it had good fatigue resistance and self‐recovery; Besides, the tear resistance of IAHDP‐1.2 could reach 35.24 kJ/m2. Interestingly, IAHDP‐1.2 also displayed shape memory characteristics, and the sample could be restored to its original state at 60°C. The synthetic IAHDP‐x also had excellent flame retardancy, high mechanical properties, fatigue resistance, tear resistance, shape memory, so the material can be used in satellite wings, solar panels, electronic and electrical equipment, and smart materials.