Chimeric Plastics: A New Class of Thermoplastics
A new class of thermoplastics (dubbed “chimerics”) is described that exhibits a high temperature glass transition followed by high performance elastomer properties, prior to melting. These transparent materials are comprised of cocontinuous phase-separated block copolymers. One block is an amorphous...
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Published in | Macromolecules Vol. 44; no. 4; pp. 865 - 871 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Washington, DC
American Chemical Society
22.02.2011
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Subjects | |
Online Access | Get full text |
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Summary: | A new class of thermoplastics (dubbed “chimerics”) is described that exhibits a high temperature glass transition followed by high performance elastomer properties, prior to melting. These transparent materials are comprised of cocontinuous phase-separated block copolymers. One block is an amorphous glass with a high glass transition temperature, and the second is a higher temperature phase transition block creating virtual thermoreversible cross-links. The material properties are highly influenced by phase separation on the order of 10−30 nm. At lower temperatures the polymer reflects the sum of the block copolymer properties. As the amorphous phase glass transition is exceeded, the virtual cross-links of the higher temperature second phase dominate the plastic properties, resulting in rubber-like elasticity. This article will particularly focus on plastics produced from phthalate-based polyester amorphous phases extended by urethane-derived second phases. Glass transitions from approximately 100−115 °C and subsequent elastomer phases to 150 °C are measured. The polymers exhibit high modulus (G′ = 1 GPa), surprisingly high toughness (up to 2 times that of Bis-A polycarbonate) below the glass transition, and very high elongations and very low elastomer set subsequently. Materials are characterized by X-ray diffraction, DSC, AFM, dynamic mechanical spectroscopy, and tensile measurements. These materials may vastly simplify thermoplastic processes requiring high melt elasticity. |
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ISSN: | 0024-9297 1520-5835 |
DOI: | 10.1021/ma102362b |