STYRENE-ACRYLATE COPOLYMERS AS TONER RESINS - CORRELATIONS BETWEEN MOLECULAR-STRUCTURE, VISCOELASTIC BEHAVIOR, AND FUSING PROPERTIES

Correlations between molecular weights and polydispersities of various styrene-acrylate resins, the temperature dependence of the viscoelast ic properties of molten toners based on these polymers, and their fusi ng properties are discussed. Toner resins with molecular weight 85,000 -300,000 and polydispersity between 5 and 19 were measured. Samples wi th high and low amounts of crosslinking agent, as well as with monomod al and bimodal molecular weight distributions, were also compared. Sto rage modulus and loss modulus were evaluated in the temperature range 110-degrees-C-200-degrees-C. Three classes can be defined in which pol ymer structures correlate with rheological and fixing behaviors. A pre diction of the fixing behavior of the toners is possible to some exten t after interpretation of rheological measurements taken on the raw po lymers.