Rapid seawater‐degradable PBSG/PVA blends: Easy water solubility and easy hydrolysis dual‐promoting degradation

Abstract

In order to shorten the degradation incubation period of existing seawater‐degradable materials and achieve “disappearance” in seawater as soon as possible, based on the successful introduction of hydrolyzed sites GA into the PBS main chain to obtain the PBSG copolymer matrix, water‐soluble PVA is introduced to finally obtain a series of PBSG/PVA blends, aiming to promote the hydrolysis process of polyester matrix by the dual action of water‐soluble PVA and easily hydrolyzed site GA. Compared with pure polyester, PBSG/PVA blends exhibt rapid loss of mechanical properties, weight loss and molecular weight drop in seawater. Among them, PBSG50/PVA0588 = 50/50 with the fastest degradation rate completely loses its mechanical properties within 1 week, and its molecular weight decreases by about 97% after 417 days. In the first 51 days of degradation, the swelling and dissolution of PVA can effectively accelerate the decrease of the molecular weight of polyester matrix, and the Mn decreases by about 50%–80%, which is much higher than that of pure polyester (about 40%). After 417 days in the late stage of degradation, compared with PBS/PVA blends, the easy hydrolysis of GA promots the obvious degradation of the matrix, and the weight loss of matrix can reach 20%.