Influence of N,N′‐ethylene bis oleamide on the flowability of the acrylonitrile‐butadiene‐styrene resin and lubrication mechanism

As a high‐performance engineering plastic, the acrylonitrile‐butadiene‐styrene (ABS) resin possesses excellent heat resistance, chemical resistance, and toughness. However, there is a lack of flow properties of the ABS resin for many processing operations. With the aim of enhancing the flowability of the ABS resin, the effect of N,N′‐ethylene bis oleamide (EBO) as a new lubricant on the melt flow rate (MFR), torque value, and rheological behavior of the ABS resin was investigated. The result showed the MFR of the ABS resin with 2.0 wt% EBO was 22.1 g/10 min, which was improved by 49% compared with the pure ABS resin (14.8 g/10 min). The torque value of the ABS resin, including 2.0 wt% EBO (1.69 N m) was lower than that of the pure ABS resin (2.03 N m). The rheological study further indicated that EBO can reduce the complex viscosity of the ABS resin. The above results indicated that EBO was an effective lubricant for the ABS resin. A possible lubrication mechanism was proposed based on the consequences of the rotational rheometry, dynamic mechanical analysis, and molecular dynamics simulation. EBO decreased the entanglement density of the polystyrene‐acrylonitrile (SAN) molecular chains and increased the mobility of the SAN molecular chain segments. On the other hand, EBO increased the free space of motion of the SAN molecular chain segments due to the free‐volume effect thereby increasing the mean square displacement of the system. This work will provide a new way to achieve the high‐flow ABS resin and provide new insights into the lubrication mechanism of lubricants in the ABS resin thereby expanding the applications of the ABS resin.