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Poly (styrene-b-butadiene-b-styrene) (SBS) triblock copolymer templates have been prepared by solvent-induced order-disorder phase transition method. Silver nanoclusters have been deposited onto the SBS copolymer templates by low energy clusters beam deposition (LECBD) method. The microstructures of the template and cluster deposits have been characterized by AFM with tapping-mode. It is shown that the triblock copolymers are self-assembled to form an in-plane cylinder ordered microstructure. In the case of low coverage (<50%), silver nanaoclusters deposited on the template tend to aggregate along with the pattern of the template and coalesce into larger nanoparticles. Optical absorption spectra reveal that the surface plasmon resonance (SPR) of silver nanoclusters deposited on the template occurs at 545nm, being a red shift of ~75nm compared to that silver nanoclusters deposited on the fused quartz substrate.

Poly(styrene-b-butadiene-b-styrene) (SBS) triblock copolymer templates which present an in-plane cylinder pattern have been prepared by controlling the solvent evaporation rate. Then silver clusters have been deposited onto the SBS copolymer templates by low energy clusters beam deposition (LECBD) apparatus. The morphology of the sample has been characterized by AFM with tapping-mode. It is shown that silver clusters aggregate into nanoparticle chains onto the template at about 100% coverage. Optical absorption spectra reveal that the surface plasmon resonance (SPR) of silver nanoparticle chains occurs at 550 nm, being a red shift of -85 nm compared to silver nanoclusters deposited on the fused quartz substrate, and the width of SPR peak broadens.

The free energy of a ternary system, such as a triblock copolymer, is a sum of two parts: an interface energy determined by the size of the interfaces separating the micro-domains of the three constituents, and a long range interaction energy that serves to prevent unlimited micro-domain growth. In two dimensions a parameter range is identified where the system admits stable stationary disk assemblies. Such an assembly consists of perturbed disks made from either type-I constituent or type-II constituent. All the type-I disks have approximately the same radius and all the type-II disks also have approximately the same radius. The locations of the disks are determined by minimization of a function. Depending on the parameters, the disks of the two types can be mixed in an organized way, or mixed in a random way. They can also be fully separated. The first scenario offers a mathematical proof of the existence of a morphological phase for triblock copolymers conjectured by polymer scientists. The last scenario shows that the ternary system is capable of producing two levels of structure. The primary structure is at the microscopic level where disks form near-perfect lattices. The secondary structure is at the macroscopic level forming two large regions, one filled with type-I disks and the other filled with type-II disks. A macroscopic, circular interface separates the two regions.

Au(0) metallic nanoparticles (Au NPs) were first prepared in triblock copolymer poly (methyl vinyl ether) PMVE-water dispersions. The wax formed from cloud point appearance in PMVE (0.6 wt.%)-water on heating the solution at 40°C worked as a template to trap the reduced AuNPs of 3 nm (σ = 0.8) size. Cooling the solution to 25°C, the cloud point disappeared as a result the particles aggregated to larger oval shape crystals with major and minor diameters 99.5 nm (σ = 4.5) and 84 nm (σ = 2), respectively when solution was stirred for one week for the completion of reaction. Smaller (4.4. nm (σ = 1.2)) particles were obtained when Au salt HAuCl₄⋅3H₂O (hydrogen tetrachloroaurate (III) trihydrate) was reduced by 5 equivalents of NaBH₄, whereas the addition of 10 equivalents NaOH gave larger particles of 13 nm (σ = 2.4) diameter. PMVE polymer alone acted as a reducing and stabilizing agent but the time of completion of reduction was much longer (one week) compared to the reduction conducted by NaBH₄ or NaOH where the reaction completed in 15 min. In neat PMVE polymer-water dispersions a number of mixing methods employed to reduce Au salt followed the order: combination of sonication and stirring > sonication > stirring. Au NPs formation was 27%, 21%, and 5%, respectively in 4 h of reaction time. The mixing experiments justified the development of microchannel mixers for NPs production on a large scale.

A kind of novel triblock copolymers of poly(γ-benzyl L-glutamate)-b-poly(tetrahydrofuran)-b-poly(γ-benzyl L-glutamate)s (PBLG-b-PTHF-b-PBLG) was synthesized by using bis(3-aminopropyl) terminated polytetrahydrofuran to initiate the ring-opening polymerization of γ-benzyl L-glutamate N-carboxyanhydride (BLG-NCA). The corresponding multiblock poly(amino acid-urea)s were prepared in one-pot protocol from the chain extension of PBLG-b-PTHF-b-PBLG with MDI. The resulting triblock and multiblock copolymers were characterized by FTIR, ¹H-NMR, ¹³C-NMR and GPC techniques. It is demonstrated that the chain extension has taken place to give rise to the copolymers with the well-defined block composition and narrow molecular weight distribution. A distinct T_g arising from the hard-segments was observed in all the copolymers. Their mechanical properties showed an increasing trend with the molecular weight enhancement of the prepolymers.