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Updated: Oct 23, 2025
Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Unique Optical Periodicity Assembly of Discrete Dendritic Lamellae and Pyramidal Single Crystals in
Selvaraj Nagarajan1, Eamor M Woo1
1Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan.
Abstract:
A unique zig-zag banded morphology poly(ε-caprolactone) (PCL), crystallized at high Tc = 46-47 °C and confined in thin films (<1 μm), is found to be assembled of parallel cogrowth of two totally crystal entities: edge-on dendritic lamellar protrusion from surfaces and flat-on pyramidal single crystals. The alternating PCL optical bands are assembled as flat-on single crystals aligned as straight dendrites as a valley band in series with edge-on branches as a ridge band, leading to a unique assembly mechanism of periodic optical rings where these two crystal pieces are assembled in series. Detailed assembly mechanisms are proposed to explain how the composite bands in the PCL aggregates are correlated to optical birefringence periodicity. By techniques of melt crystallization via periodic species drainage, PCL single crystals could be prepared and tailor-made to a variety of nanopatterns as templates for applications.
