access to supercomputers and to fast networks, but also on improved force fields, deeper connections to quantum mechanics, and better treatments of the environment of surrounding and entangled chains or solvents. Better quantum mechanical methods are needed to treat large numbers of electrons and atoms.

• Practical challenges include applying theory and computation to polymer behaviors in complex media—polymer blends, liquid crystalline polymers, semicrystalline materials, composites, block copolymers, interfaces, the rheology of mixtures, branched molecules, soft matter, and so on.

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