• cellulose acetate;
  • poly(ε-caprolactone);
  • poly (vinyl pyrrolidone-co-vinyl acetate)-graft-poly(ε-caprolactone);
  • macro monomer;
  • compatibilizer;
  • biodegradable;
  • compatibilization;
  • graft copolymers


Poly(vinyl pyrrolidone-co-vinyl acetate)-graft-poly(ε-caprolactone) (PVPVAc-g-PCL) was synthesized by radical copolymerization of N-vinyl-2-pyrrolidone (VP)/vinyl acetate (VAc) comonomer and PCL macromonomer containing a reactive 2-hydroxyethyl methacrylate terminal. The graft copolymer was designed in order to improve the interfacial adhesiveness of an immiscible blend system composed of cellulose acetate/poly(ε-caprolactone) (CA/PCL). Adequate selections of preparation conditions led to successful acquisition of a series of graft copolymer samples with different values of molecular weight ( equation image), number of grafts (n), and segmental molecular weight of PVPVAc between adjacent grafts (Mn (between grafts)). Differential scanning calorimetry measurements gave a still immiscible indication for all of the ternary blends of CA/PCL/PVPVAc-g-PCL (72 : 18 : 10 in weight) that were prepared by using any of the copolymer samples as a compatibilizer. However, the incorporation enabled the CA/PCL (4 : 1) blend to be easily melt-molded to give a visually homogeneous film sheet. This compatibilizing effect was found to be drastically enhanced when PVPVAc-g-PCLs of higher equation image and Mn (between grafts) and lower n were employed. Scanning electron microscopy revealed that a uniform dispersion of the respective ingredients in the ternary blends was attainable with an assurance of the mixing scale of several hundreds of nanometers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009