SEC analysis was performed on an Agilent 1260 Infinity II system combined with refractive index (RI) and ultraviolet (UV) detectors (λ = 309 and 360 nm), equipped with a PLGel 3 µm (50 × 7.5 mm) guard column and two PLGel 5 µm (300 × 7.5 mm) mixed-D columns, mobile phase (eluent) is CHCl 3 with 0.5% triethylamine (TEA). Molecular weight (M w ) and molecular weight distributions were calibrated against poly(methyl methacrylate) (PMMA) standards and analyzed using Agilent SEC software. without stirring on a heating block for 3 h before cooling to room temperature and then aging for 5 days to yield micron-length polydisperse fibers (Fig. ). The crystalline fibers were then sonicated using a Bandelin Sonopuls sonication probe in a dry-ice/acetone bath for 20 min. The polymer solution was exposed to 60 cycles of 20 s bath sonication with an interval of 100 s to yield a short crystalline seed stock solution (Fig. ). For determination of the average length of the seed, a minimum number of 100 seeds were analyzed with TEM (Fig. ). to form a targeted concentration, then aged for at least 1 h. Then a small volume of unimer stock solution was added to a dispersion of seed solution in a screw cap vial followed by shaking by hand for 5 s, the final unimer concentration was varied by adjusting the volume of stock solutions added to each reaction. At predetermined time points, 140 µL sample mixture was withdrawn and added to 140 µL of deionized water to quench the reaction, followed by subsequent analysis.