Miscibility in blends of linear and branched poly(ethylene oxide) with methacrylate derivative random copolymers and estimation of segmental gamma parameters

• Published in: Polymer (Guilford) Vol. 46; no. 25; pp. 11463 - 11469
• Main Authors: Takeshita, H, Shiomi, T, Suzuki, T, Sato, T, Miya, M, Takenaka, K, Wacharawichanant, S, Damrongsakkul, S, Rimdusit, S, Thongyai, S, Taepaisitphongse, V
• Format: Journal Article
• Language: English
• Published: 28.11.2005
• ISSN: 0032-3861
• DOI: 10.1016/j.polymer.2005.10.067

Miscibility in the blends of poly(ethylene oxide) (PEO) with n-hexyl methacrylate-methyl methacrylate random copolymers (HMA-MMA) and 2-ethylhexyl methacrylate-MMA random copolymers (EHMA-MMA) was evaluated using glass transition and light scattering methods. EHMA-MMA was more miscible with PEO than HMA-MMA. Both blends of PEO with HMA-MMA and EHMA-MMA showed UCST-type miscibility although homopolymer blends PEO/PMMA were predicted to be of LCST-type. This was attributed to an increase in the exchange enthalpy with increasing HMA or EHMA composition in the random copolymer. From the copolymer composition dependence of miscibility the segmental D*g parameters of HMA/MMA, EHMA/MMA, EO/HMA and EO/EHMA were estimated using the Flory-Huggins theory extended to random copolymer systems. Miscibility in the blends of branched PEO with HMA-MMA whose HMA copolymer composition was 0DDT16 was compared with that in the linear PEO blends. The former blends were more miscible with HMA-MMA than the latter one by about 35DDGC at the maximum cloud point temperature.