Retardation effect in acetalization of poly(vinyl alcohol) with butyraldehyde

[Display omitted] •The retardation effect in acetalization of PVA with butyraldehyde was revealed.•The anomalous retardation was observed in dilute polymer solutions.•It was explained in terms of the chain conformations.•Possible intramolecular cross-linking was also considered. The condensation reaction of butyraldehyde with poly(vinyl alcohol) at various degrees of polymer conversion was studied from the kinetic point of view. The reaction was carried out at 20–50°C. On the basis of the effective rate constants calculated from the kinetic investigations, it was inferred that the reaction proceeded with retardation as the degree of acetalization increased. The anomalous retardation was observed in dilute polymer solutions (1wt.%). The retardation effect thus revealed was explained in terms of the conformation of the polymer chains and possible side reactions.