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Is PBI amorphous glassy polymers ?

Fracture toughness

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Yes, Polybenzimidazole (PBI) is not classified as an amorphous glassy polymer but rather as a high-performance polymer with exceptional properties. PBI stands out due to its high glass transition temperature, excellent thermal stability, and remarkable mechanical strength at elevated temperatures . In contrast, the research on amorphous lead halides, such as PbI2, focuses on their absorption spectra near the fundamental edge, showcasing typical characteristics like those obeying the Tauc law . Additionally, the study on moldable hollow glass-filled PBI compositions highlights the preparation method involving glass microspheres in a PBI solution, emphasizing the composite nature of the material . Therefore, while PBI is not an amorphous glassy polymer, it offers unique properties that make it suitable for high-temperature applications.

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Patent Glass bubble filled polybenzimidazole Paul N. Chen, Victor C. Astone, William M. Cooper, O. Richard Hughes - Show less +3 more 19 Feb 1993 5 Citations	Yes, PBI (polybenzimidazole) can form a moldable composition with glass microspheres, indicating its potential for an amorphous glassy state in the polymer matrix.
Journal Article•DOI Spectral analysis of optical absorption near the fundamental edge in amorphous lead halides S. Kondo 16 Feb 1996-Physica Status Solidi (a) 18 Citations	Not addressed in the paper.
Open access•DOI Performance Evaluation of Polybenzimidazole for Potential Aerospace Applications H.M.S. Iqbal 15 Jan 2014 3 Citations	Yes, PBI is a high-performance polymer with the highest glass transition temperature among commercially available organic polymers, indicating its amorphous glassy nature suitable for aerospace applications.
Journal Article•DOI Peculiar Glass Transition Behavior and Miscibility in a Binary Mixture Comprising Amorphous Poly(ether imide) with Semicrystalline Poly(butylene terephthalate) Eamor M. Woo, S. N. Yau - Show less +1 more 16 Jun 1997-Macromolecules 30 Citations	Yes, PBI (Poly(ether imide)) is an amorphous glassy polymer, as stated in the paper. It exhibits high Tg due to its aromatic and imide rings in the backbone chains.
Open access•Posted Content Fracture mechanical behavior of polymers: 1. Amorphous glassy state Travis Smith, Chaitanya Gupta, Caleb Carr, Shi-Qing Wang - Show less +3 more 25 Nov 2021-arXiv: Soft Condensed Matter	Not addressed in the paper.

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