Jamming of semiflexible polymers

Original · EN

We study jamming in model freely rotating polymers as a function of chain length N and bond angle θ₀. The volume fraction at jamming, ϕⱼ(θ₀), is minimal for rigid-rod-like chains (θ₀ = 0), and increases monotonically with increasing θ₀ ≤ π/2. In contrast to flexible polymers, marginally jammed states of freely rotating polymers are highly hypostatic, even when bond and angle constraints are accounted for. Large aspect ratio (small θ₀) chains behave comparably to stiff fibers: resistance to large-scale bending plays a major role in their jamming phenomenology. Low aspect ratio (large θ₀) chains behave more like flexible polymers, but still jam at much lower densities due to the presence of frozen-in 3-body correlations corresponding to the fixed bond angles. Long-chain systems jam at lower ϕ and are more hypostatic at jamming than short-chain systems. Implications of these findings for polymer solidification are discussed.