Blends of poly(vinyl chloride) (PVC) and polyesteramides (PEA), based on epsilon-caprolactam and epsilon-caprolactone, were prepared to improve the notch impact strength of PVC. Miscibility of components was assessed from glass transition temperature and is limited by the amount of PEA in the blend and by the content of c-caprolactam structural units in PEA. The effects of the content and type of PEA on their thermal stability and notched impact strength were also investigated. The impact strength of the PVC blends reaches its maximum at an equimolar lactam to lactone units ratio in PEA; it decreases with increasing content of PEA in the blend. An admixture of a small amount of poly(epsilon-caprolactam) as a compatibilizer made it possible to prepare PEA-rich PVC blends, exhibiting twice as high notch impact strength, as compared to pure PVC. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 826-833, 2009