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Poly(vinyl alcohol-co-vinyl acetate) (PVA) copolymers obtained by partial hydrolysis of poly(vinyl acetate) (PVAc) are of practical importance for many applications, including emulsion and suspension polymerization processes. Their molecular characteristics have a major influence on the colloidal and interfacial properties. The most significant characteristics are represented by the average degree of hydrolysis , average degree of polymerization but also by the average acetate sequence length nVAc0 which designates the so-called blockiness. Colloidal aggregates were observed in the aqueous PVA solutions having a value of 73 mol%. The volume fraction of these aggregates at a given value is directly correlated to the blockiness. Three PVA samples with identical and but different blockiness were examined. By pendant drop and oscillating pendant drop techniques it was shown that the PVA sample having …