Combs and Bottlebrushes in a Melt

• DOI: 10.1021/acs.macromol.7b00364
• Publication Date: 2017-04-11T17:26:42Z
• Authors: Heyi Liang; Zhen Cao; Zilu Wang; Sergei S. Sheiko; Andrey V. Dobrynin
• Keywords: Side chain; Macromolecular Crowding; Excluded volume; Degree of polymerization

We use a combination of the coarse-grained molecular dynamics simulations and scaling analysis to study conformations bottlebrush comb-like polymers in melt. Our shows that crossover between comb regimes is controlled by crowding parameter, Φ, describing overlap neighboring macromolecules. In systems characterized sparse grafting side chains (Φ < 1), backbones belonging macromolecules interpenetrate. However, bottlebrushes with densely grafted ≥ interpenetration suppressed steric repulsion chains. this regime, can be viewed as filaments diameter proportional size For flexible chains, parameter given Φ ≈ [v/(lb)3/2][(nsc/ng + 1)/nsc1/2], which depends on both architectural parameters (degree polymerization nsc, number backbone bonds ng) chemical structure monomers (bond length l, monomer excluded volume v, Kuhn length, b). Molecular corroborate classification graft show effective macromolecule bK, mean-square end-to-end distance backbone, ⟨Re,bb2⟩, are universal functions for all studied systems.