Journal of Applied Polymer Science, Vol.66, No.10, 1911-1923, 1997
Compatibilization of Poly(Vinylidene Fluoride)/Nylon-6 Blends by Carboxylic-Acid Functionalization and Metal-Salts Formation .1. Grafting Reactions and Morphology
An investigation was carried out to determine the feasibility of producing compatibilized blends of PVDF and nylon 6 using a procedure involving the grafting of carboxylic acid groups on the chains of either polymer component and, subsequently, producing the corresponding metal salts. The grafting reactions were carried out by irradiating the polymer with gamma-rays at 15 kGy, followed by treatments in aqueous solutions of methacrylic acid. These conditions were established from preliminary work which also revealed that this monomer gives higher grafting yields than acrylic acid. The grafted polymers were found to have a heterogeneous structure, attributed to the presence of oligomeric, rather than unitary, side groups. Nevertheless, these modifications of the polymer chains were found to give rise to well-compatibilized blends, containing co-continuous phases which became much finer through the addition of zinc acetyl acetonate. FTIR analysis showed that the enhanced compatibilization resulted from the reactions between the acid groups in the PVDF component and the terminal amine groups of the polyamide chains. Since the addition of zinc acetyl acetonate was found to reduce the yield of amidized groups, it was inferred that the enhanced compatibilization has resulted from the complexation of zinc cations with the amide groups in the nylon 6 chains, which are shared with the carboxylate anions of the grafted PVDF component.
Keywords:INTERMOLECULAR INTERACTIONS;METHACRYLIC-ACID;POLYMER BLENDS;IONOMER BLENDS;POLYPROPYLENE;MISCIBILITY;MIXTURES;POLYSTYRENE;NYLON-6;TRANSITION