Formation of tubular scrolls with controlled internal cavity

In this work, we investigate internal cavity controlled tubular scroll formation through simple modification of tether coils that are grafted on the surface of a 2D polymer sheet. Dissipative particle dynamics simulations show that coarse-grained 2D sheets transform to various cylindrical structures including tubular and filled scrolls in the presence of broken volume and chemical symmetries of tether coils: volume (chemical) asymmetry arises when coils on one side have a different number of beads (solvent affinity) from those on the other side. It is clear from a phase diagram that the scroll formation is governed by the balance between hydrophobicity and entropy of coils. The density profiles show that a wide range of interior cavity diameter can be obtained by employing volume asymmetry on coils with weak chemical asymmetry. We provide crucial scientific insights in understanding the scroll formation through self-assembly of rod-coil molecules and suggest modification of the tether coil's properties as a practical and systematic method to form tubular scrolls with targeted internal cavity.