AbstractKinetics of solution homopolymerization ofp‐formylstyreneSystem name: 4‐vinylbenzaldehyde.(A) and copolymerization with styrene (S) have been examined at 60°C inN,N‐dimethylformamide with 2,2′‐azoisobutyronitrile as initiator. Forp‐formylstyrene,kp/k t1/2= 0,135 L1/2· mol−1/2· s−1/2was estimated from the plot of monomer consumption versus time, i.e. a value greater than that for styrene (KpandKtare the rate constants of propagation and termination and termination, respectively). Reactivity ratios have been determined to berA= 3,0 andrS= 0.2, indicating the reactivity ofp‐formylstyrene to be higher than that of styrene. Moreover, from initial copolymerization rates, the cross termination factor was calculated and found to depend upon the copolymer composition. Some solution properties of the homo‐ and copolymers have been analysed: solubility of (co)polymers, their molecular weight and its distribution (by gel permeation chromatography), and their composition and monomer sequence distribution (using1H