Study on composting and seawater degradation properties of diethylene glycol-modified poly(butylene succinate) copolyesters

The marine pollution caused by traditional plastics is becoming increasingly serious, and the fundamental way to solve this problem is to look for plastic substitutes that can degrade in the marine environment. Herein, a series of high-molecular-weight poly(butylene succinate-co-diethylene glycol succinate) (PBDS) was obtained by the introduction of low-cost diethylene glycol (DEG) into the main chain of poly(butylene succinate) (PBS), which aimed to obtain the materials that can be degraded both in compost and seawater. The research showed that the increase in the DEG content reduced the crystallinity of the copolyester, which led to the decrease in mechanical strength and thermal properties of the copolyester to a certain extent. Meanwhile, the increase in hydrophilicity and the decrease in crystallinity improved the degradation rate of the material. Compared with PBS, PBDS exhibited not only a faster composting degradation rate but also a faster degradation rate in seawater.