We study how solidification of model freely rotating polymers under athermal quasistatic compression varies with their bond angle θ₀. All systems undergo two discrete, first-order-like transitions: entanglement at ϕ = ϕ_E(θ₀) followed by jamming at ϕ = ϕ_J(θ₀) ≃ (4/3 ± 1/12)ϕ_E(θ₀). For ϕ < ϕ_E(θ₀), systems are in a “gas” phase wherein all chains remain free to translate and reorient. For ϕ_E(θ₀) ≤ ϕ ≤ ϕ_J(θ₀), systems are in a liquid-like phase wherein chains are entangled. In this phase, chains' rigid-body-like motion is blocked, yet they can still locally relax via dihedral rotations, and hence energy and pressure remain extremely small. The ability of dihedral relaxation mechanisms to accommodate further compression becomes exhausted, and systems rigidify, at ϕ_J(θ₀). At and slightly above ϕ_J, the bulk moduli increase linearly with the pressure P rather than jumping discontinuously, indicating these systems solidify via rigidity percolation. The character of the energy and pressure increases above ϕ_J(θ₀) can be characterized via chains' effective aspect ratio α_eff. Large-α_eff (small-θ₀) systems' jamming is bending-dominated and is similar to that observed in systems composed of straight fibers. Small-α_eff (large-θ₀) systems' jamming is dominated by the degree to which individual chains' dihedrals can collapse into compact, tetrahedron-like structures. For intermediate θ₀, chains remain in highly disordered globule-like configurations throughout the compression process; jamming occurs when entangled globules can no longer even locally relax away from one another.

中文翻译：

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半柔性聚合物和纤维的两阶段非热固化。

我们研究如何模型的凝固自由旋转的无热下压缩准静态聚合物因人而异与它们键角θ ₀。所有的系统都经历两个离散的一阶状过渡：缠结在φ = φ _È（θ ₀），然后在干扰φ = φ _Ĵ（θ ₀）≃（4/3±1/12）φ _È（θ ₀）。对于φ < φ _È（θ ₀），系统在“气体”相，其中所有连锁保持自由平移和调整。对于ϕ _E（θ ₀）≤ φ ≤ φ _Ĵ（θ ₀），系统是在液体状的相，其中链缠结。在此阶段，链条的刚性运动被阻止，但是它们仍然可以通过二面角旋转局部松弛，因此能量和压力仍然非常小。的二面角松弛机制以适应进一步压缩的能力变得耗尽，以及系统刚性化，在φ _Ĵ（θ ₀）。在和略高于φ _Ĵ时，体积模量随压力线性地增加P而不是不连续地跳跃，这表明这些系统通过刚度渗透得以固化。的上述的能量和压力的增加而字符φ _Ĵ（θ ₀）的特征可在于通过链有效纵横比α _EFF。Large- α _EFF（小θ ₀）系统干扰被弯曲为主，是类似于在直纤维组成系统中观察到。小α _EFF（large- θ ₀）系统的干扰主要取决于各个链的二面体塌陷成紧凑的四面体状结构的程度。对于中间θ ₀，链条保持在高度无序球样在整个压缩过程配置; 当纠缠的小球甚至不能再彼此局部放松时，就会发生阻塞。