Amphiphilic diblock copolymer polycaprolactone-block-poly(glycidyl methacrylate) (PCL-b-PGMA) was synthesized via enzymatic ring-opening polymerization (eROP) and atom transfer radical polymerization (ATRP). Methanol first initiated eROP of e-caprolactone (e-CL) in the presence of biocatalyst Novozyme-435 under anhydrous conditions. The resulting monohydroxyl-terminated polycaprolactone (PCL-OH) was subsequently converted to a bromine-ended macroinitiator (PCL-Br) for ATRP by esterification with a-bromopropionyl bromide. PCL-b-PGMA diblock copolymers were synthesized in a subsequent ATRP of glycidyl methacrylate (GMA). A kinetic analysis of ATRP indicated a living/controlled radical process. The macromolecular structures were characterized for PCL-OH, PCL-Br, and the block copolymers by means of nuclear magnetic resonance, gel permeation chromatography, and infrared spectroscopy. Differential scanning calorimetry and wide-angle X-ray diffraction analyses indicated that the copolymer composition (e-CL/GMA) had a great influence on the thermal properties. The well-defined, amphiphilic diblock copolymer PCL-b-PGMA self-assembled into nanoscale micelles in aqueous solutions, as investigated by dynamic light scattering and transmission electron microscopy. V V C 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5037-5049, 2007

A symmetric linear CBABC pentablock copolymer consisting of poly(ethylene oxide) (PEO), polycaprolactone (PCL), and polystyrene (PSt) was synthesized by the combination of enzymatic ring-opening polymerization (eROP) and atom transfer radical polymerization (ATRP). Dihydroxyl-capped PEO first initiated eROP of -CL in the presence of biocatalyst Novozyme 435. Subsequently, the resulting dihydroxyl-terminated copolymer PCL-b-PEO-b-PCL was converted to bromine-ended triblock macroinitiator by the esterification with R-bromopropionyl bromide. Pentablock copolymer PSt-b-PCL-b-PEO-b-PCL-b-PSt was obtained via a subsequent ATRP of styrene(St), and its kinetics analysis indicated a "living"/controlled radical polymerization. The selfassembly behavior of pentablock copolymer was investigated in aqueous media. The "crew-cut" aggregates of various morphologies were observed, such as normal spherical micelles, rodlike micelles, vesicles, lamellae, and large compound micelles (LCMs). In addition, it was found that both the copolymer composition and the copolymer concentration in THF had a great influence on the morphologies of the aggregates.

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In this paper, we introduced geometric algebra to develop a new multisource multisink optimal evacuation route planning method. A dynamically updatable data structure and a matrix‐based greedy searching algorithm were developed to support the dynamic evacuation route searching for multiple evacuees. Unlike most existing methods, which iteratively search the optimal path for each evacuee, our method can search all the possible evacuation routes synchronously. The dynamic updating of the network topography, weights, and constraints during the route searching is direct and flexible, thus can support the evacuation in dynamic cases. The method is demonstrated and tested by an evacuation case in the city of Changzhou, China. The simulation experiments suggest that the method can well support the dynamic route searching in large scales with dynamic weight changes.

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