Molecular mixing of incompatible polymers through formation of and coalescence from their common crystalline cyclodextrin inclusion compounds

• Published in: Journal of polymer science. Part B, Polymer physics Polymer physics, 2004-12, Vol.42 (23), p.4207-4224
• Main Authors: Rusa, C. C., Wei, M., Shuai, X., Bullions, T. A., Wang, X., Rusa, M., Uyar, T., Tonelli, A. E.
• Format: Article
• Language: English
• Subjects: Applied sciences; block copolymers; compatibilization; cyclodextrin; Exact sciences and technology; inclusion complexes; intimate mixing; Organic polymers; Physicochemistry of polymers; polymer blends; Properties and characterization; Thermal and thermodynamic properties
• ISSN: 0887-6266; 1099-0488
• DOI: 10.1002/polb.20272

We describe the successful mixing of polymer pairs and triplets that are normally incompatible to form blends that possess molecular‐level homogeneity. This is achieved by the simultaneous formation of crystalline inclusion compounds (ICs) between host cyclodextrins (CDs) and two or more guest polymers, followed by coalescing the included guest polymers from their common CD–ICs to form blends. Several such CD–IC fabricated blends, including both polymer1/polymer2 binary and polymer1/ polymer2/polymer3 ternary blends, are described and examined by means of X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, and solid‐state NMR to probe their levels of mixing. It is generally observed that homogeneous blends with a molecular‐level mixing of blend components is achieved, even when the blend components are normally immiscible by the usual solution and melt blending techniques. In addition, when block copolymers composed of inherently immiscible blocks are coalesced from their CD–ICs, significant suppression of their normal phase‐segregated morphologies generally occurs. Preliminary observations of the thermal and temporal stabilities of the CD–IC coalesced blends and block copolymers are reported, and CD–IC fabrication of polymer blends and reorganization of block copolymers are suggested as a potentially novel means to achieve a significant expansion of the range of useful polymer materials. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4207–4224, 2004