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   https://doi.org/10.1002/9783527815562.mme0064  

   Connie B. Roth ( March 2022 , Macromolecular Engineering: From Precise Synthesis to Macroscopic Materials and Applications)

   Matyjaszewski, Krzysztof ; Gnanou, Yves ; Hadjichristidis, Nikos ; Muthukumar, Murugappan (Ed.)

   Polymers exist in the glass state for a wide range of applications. The slow and limited crystallizability of polymers means that solid polymer materials are either wholly or in part glassy, giving them great importance. The glass is a nonequilibrium amorphous state that occurs because the cooperative molecular dynamics become kinetically trapped on cooling as the available thermal energy for molecular motion decreases. This article aims to provide the reader with a molecular picture of what this packing frustration that causes glass formation means for polymers. Experimental considerations for accurately measuring the glass transition temperature 𝑇𝑔 given this nonequilibrium nature will be discussed. Basic concepts underpinning theoretical efforts to model the glass transition will be summarized to provide the reader with a lexicon and paradigm for understanding different approaches used in the field to capture the main characteristics of glasses. Current research areas of interest in polymer glasses will be briefly outlined. Hopefully, this article will provide the beginning investigator a starting point for their own studies. 

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2. Anisotropic organic glasses

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3. Isochoric structural recovery in molecular glasses and its analog in colloidal glasses

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   Banik, Sourya ; McKenna, Gregory B. ( June 2018 , Physical Review E)
4. Energy transport in glasses

   https://doi.org/10.1039/c9sm02171j  

   Flenner, Elijah ; Wang, Lijin ; Szamel, Grzegorz ( January 2020 , Soft Matter)

   The temperature dependence of the thermal conductivity is linked to the nature of the energy transport at a frequency ω , which is quantified by thermal diffusivity d ( ω ). Here we study d ( ω ) for a poorly annealed glass and a highly stable glass prepared using the swap Monte Carlo algorithm. To calculate d ( ω ), we excite wave packets and find that the energy moves diffusively for high frequencies up to a maximum frequency, beyond which the energy stays localized. At intermediate frequencies, we find a linear increase of the square of the width of the wave packet with time, which allows for a robust calculation of d ( ω ), but the wave packet is no longer well described by a Gaussian as for high frequencies. In this intermediate regime, there is a transition from a nearly frequency independent thermal diffusivity at high frequencies to d ( ω ) ∼ ω −4 at low frequencies. For low frequencies the sound waves are responsible for energy transport and the energy moves ballistically. The low frequency behavior can be predicted using sound attenuation coefficients. 

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5. Surface dynamics of glasses

   https://doi.org/10.1063/5.0083726  

   Tian, Houkuan ; Xu, Quanyin ; Zhang, Haiyang ; Priestley, Rodney D. ; Zuo, Biao ( March 2022 , Applied Physics Reviews)

   Two challenging scientific disciplines, i.e., the physics of glasses [Anderson, Science 267, 1615 (1995); Kennedy and Norman, Science 309, 75 (2005)] and interface chemistry [Sanders, 125 Questions: Exploration and Discovery (Science/AAAS, 2021); Yates and Campbell, Proc. Natl. Acad. Sci. U. S. A. 108, 911 (2011)], converge in research on the dynamics of glass surfaces. In recent decades, studies have revealed that glasses exhibit profound alterations in their dynamics within nanometers of interfaces. Rather, at the free surfaces of glassy materials with arrested bulk dynamics, a highly mobile ultrathin layer is present, wherein molecular mobility is much faster than in the bulk. Enhanced surface mobility has become an important scientific concept and is intrinsic and universal to various categories of glasses (e.g., molecular, metallic, and polymeric glasses), thus having technological implications for processing and applications of glasses. This review provides a comprehensive summary of the historical evolution of the concept, characterization, theoretical modeling, and unique features of dynamics at the surfaces of glasses. Additionally, this paper also illustrates potential advantages of incorporating this concept into designing improved materials with extraordinary properties. We hope this review article will contribute to the current understanding of the unique surface dynamics of glassy materials.

    

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