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1. Morphologies of Polyisoprene-Grafted Silica Nanoparticles in Model Elastomers

   https://doi.org/10.1021/acs.macromol.9b01479  

   Bonnevide, Marine; Jimenez, Andrew M.; Dhara, Deboleena; Phan, Trang N.T.; Malicki, Nicolas; Abbas, Zaid M.; Benicewicz, Brian; Kumar, Sanat K.; Couty, Marc; Gigmes, Didier; et al (October 2019, Macromolecules)
2. Vapor phase infiltration of zinc oxide into thin films of cis -polyisoprene rubber

   https://doi.org/10.1039/D0MA00304B  

   Pilz, Julian; Coclite, Anna Maria; Losego, Mark D. (January 2020, Materials Advances)

   Elastomers are an important class of polymers for many applications. Often, additives are added to the polymer matrix of elastomers to promote vulcanization or enhance physical or chemical properties. In this study, vapor phase infiltration (VPI) is investigated for transforming unvulcanized cis -polyisoprene (from natural rubber) into an organic/inorganic hybrid material. Specifically, we examine single-cycle infiltration with diethylzinc (DEZ) and water to form infiltrated zinc oxide species. Interestingly, low-temperature pre-heating of the cis -polyisoprene acutely affects the processes of infiltration, including diffusivity, maximum solubility, and chemical reactivity. We attribute these effects to a combination of film relaxation and oxidation. Independent of thermal pre-treatments, all infiltration processes exhibited consistent zinc oxide loading irrespective of purge time between the DEZ and water doses, indicating the presence of a strongly bound intermediate state between the DEZ precursor and the cis -polyisoprene polymer. Increasing infiltration process temperature accelerates diffusion and lowers the maximum solubility, in accordance with Fick's law and gas phase sorption equilibrium. Resulting organic–inorganic hybrid films show enhanced resistance to dissolution in toluene, a good solvent for the pure polymer. 

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3. SiO ₂ ‑g‑Polyisoprene Particle Brush Reinforced Advanced Elastomer Nanocomposites Prepared via ARGET ATRP

   https://doi.org/10.1002/adfm.202315741  

   Liu, Yingxue; Wang, Zongyu; Zhao, Yuqi; Hou, Guanyi; Jiang, Ruifeng; Bockstaller, Michael R; Qin, Xuan; Zhang, Liqun; Matyjaszewski, Krzysztof (June 2024, Advanced Functional Materials)

   Abstract Nanoparticle reinforcement is a general approach toward the strengthening of elastomer nanocomposite in large‐scale applications. Extensive studies and efforts have been contributed to demonstrating the property reinforcement of polymer nanocomposites in relation to matrix‐filler and filler‐filler interaction. Here, a facile synthetic method is creatively reported to synthesize SiO_2,15/120‐g‐polyisoprene (SiO₂‐g‐PI) particle brushes using atom transfer radical polymerization (ATRP). The dispersion and microstructures of the nanoparticles in the nanocomposites are investigated by morphological characterizations, whereas the reinforcing mechanism is studied through mechanical measurements as well as computational simulation. Remarkably, compared with the cured bulk elastomers and matrix(M)/SiO₂blends, M/particle brushes (PB) exhibit significant improvement in mechanical properties, including tensile strength, elongation at break, modules, and rolling resistance. This elastomer nanocomposites afford a novel prospect for the practical application of next‐generation automobile tires with enhanced performance. 

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4. Synthesis of Mechanically Robust Very High Molecular Weight Polyisoprene Particle Brushes by Atom Transfer Radical Polymerization

   https://doi.org/10.1021/acsmacrolett.4c00089  

   Zhao, Yuqi; Wang, Zongyu; Hou, Guanyi; Wu, Hanshu; Fu, Liye; Bockstaller, Michael R.; Qin, Xuan; Zhang, Liqun; Matyjaszewski, Krzysztof (March 2024, ACS Macro Letters)
5. Effective Ultrapowers and Applications; Aspects of Computation and Automata Theory with Applications

   https://doi.org/10.1142/9789811278631_0008  

   Dimitrov, Rumen D; Harizanov, Valentina (November 2023, WORLD SCIENTIFIC)

   Greenberg, Noam; Jain, Sanjay; Ng, Keng Meng; Schewe, Sven; Stephan, Frank; Wu, Guohua; Yang, Yue (Ed.)

   We give a systematic account of the current state of knowledge of an e↵ective analogue of the ultraproduct construction. We start with a product of a uniformly computable sequence of computable structures indexed by the set of natural numbers. The equality of elements and sat- isfaction of formulas are defined modulo a subset of the index set, which is cohesive, i.e., indecomposable with respect to computably enumerable sets. We present an analogue of Lo ́s’s theorem for e↵ective ultraprod- ucts and a number of results on definability and isomorphism types of the e↵ective ultrapowers of the field of rational numbers, when the com- plements of cohesive sets are computably enumerable. These e↵ective ultraproducts arose naturally in the study of the automorphisms of the lattice of computably enumerable vector spaces. Previously, a number of authors considered related constructions in the context of nonstandard models of fragments of arithmetic. 

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