Effective Interaction Parameter for Homologous Series of Deuterated Polystyrene-block-Poly(n-alkyl methacrylate) Copolymers

Autor:	Junhan Cho, Changhak Shin, Thomas P. Russell, Jin Kon Kim, Kristopher A. Lavery, Dong Hyun Lee, Du Yeol Ryu
Rok vydání:	2007
Předmět:	Polymers and Plastics Organic Chemistry Thermodynamics Flory–Huggins solution theory Neutron scattering Methacrylate Small-angle neutron scattering Inorganic Chemistry Homologous series chemistry.chemical_compound chemistry Polymer chemistry Materials Chemistry Copolymer Polystyrene Phase diagram
Zdroj:	Macromolecules. 40:7644-7655
ISSN:	1520-5835 0024-9297
DOI:	10.1021/ma070754z
Popis:	The effective interaction parameters, (χF) of the homologous series of deuterated polystyrene-block-poly(n-alkyl methacrylate) copolymers (dPS-b-PAnMA) from methyl (n = 1) to hexyl (n = 6) side groups have been investigated by small-angle neutron scattering and a Hartree (fluctuation correction) analysis. While χF for dPS-b-PAnMA with n = 1 and 6 is a typical decreasing function of temperature, it is shown that χF for n from 2 to 4 changes to a monotonic increase with temperature, revealing growing upward convexity. This action culminates in a maximum of χF for n = 5, which suggests an immiscibility loop-type behavior. Using the Hartree analysis for compressible diblock copolymers, the effect of directional interactions and the compressibility difference between the constituent blocks on χF is discussed. The ordering transition temperatures, their pressure dependences, and χF for the homologous block copolymer series are shown to be in good agreement with the experimental values.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::679ea7b4ba40fc88d3924e03ae624228 https://doi.org/10.1021/ma070754z Zobrazit plný text záznamu