The negative biodegradation of poly(vinyl alcohol) modified by aldehydes

An obvious decrease in biodegradation levels of all the modified samples was found, and a decrease in biodegradation level with increasing degree of acetals of PVA. The biodegradation of poly(vinyl formal) is better than poly(vinyl butyral) with the same degree of acetals whereas the biodegradation levels of poly(vinyl glyoxal) are lower than poly(vinyl glutaral) which has the same degree of crosslinking. The difference between the FT-IR of the samples before and after biodegradation indicated scission of residual PVA chain during the process.