Synthesis Of Polymer Particles Research Articles

Continuous Microfluidic Reactors for Polymer Particles

This article provides an overview of our work in the area of the synthesis of polymer particles in continuous microfluidic reactors. The method includes (a) the generation of highly monodisperse monomer droplets in a microfluidic flow-focusing device and (b) in-situ solidification of these droplets by means of photopolymerization. We discuss the effect of monomer properties on the emulsification process, the effect of the polymerization rate on the production of high-quality particles, the role of the material of the microfluidic device in droplet formation, and the synthesis of particles with different shapes and compositions. We also demonstrate the production of highly ordered arrays of polymer particles achieved by photopolymerization of the dynamic lattices of monomer droplets in microfluidic channels. The article is concluded with a summary of future research directions in the production of polymer colloids in microfluidic reactors.

Polymer Particles with Various Shapes and Morphologies Produced in Continuous Microfluidic Reactors

We report a novel approach to continuous and scalable production of core-shell droplets and polymer capsules in microfluidic devices. The described method is also useful in the synthesis of polymer particles with nonspherical shapes. We used capillary instability-driven break-up of a liquid jet formed by two immiscible fluids. Precise control of emulsification of each liquid allowed for the production of highly monodisperse core-shell droplets with a predetermined diameter of cores and thickness of shells. We also achieved control over the number of cores per droplet and the location of cores in the droplet. We carried out fast throughput photopolymerization of the monomeric shells and obtained polymer particles with various shapes and morphologies, including spheres, truncated spheres and, hemispheres, and single and multicore capsules.

Multilayer Polymer Particles with Periodic Modulation in Refractive Index

We report synthesis of polymer particles comprising layers with alternating high and low refractive index. We used poly(heptafluorobutyl methacrylate) as the low refractive index component and polystyrene as the high refractive index counterpart. We employed a copolymerization approach, the addition of a phase transfer catalyst (cyclodextrin), and a mixed initiator approach to produce spherical particles with a well-defined morphology. The composition and morphology of these particles were proven by DSC, XPS, NMR, and SEM. The refractive index contrast between these alternating high and low refractive index layers was ca. 0.20 ± 0.018. This work shows a route toward synthesis of polymeric spherical dielectric resonators.

Influence of polymeric non-ionic surfactants on the surface tension of styrene and on the styrene polymerization process

Dynamic surface tension of non-ionic surfactants pluronic F-168 and poly(dimethylsiloxan) bis(hydroxyalkyl) terminated (PDS) were studied using the drop profile analysis tensiometry. The comparison of these data with those from styrene heterophase polymerization studies show that only in the PDS:pluronic mixing ratio range between 1:0.2 and 1:0.8 the contribution of each surfactant component manifests its effect and provides appropriate conditions for the synthesis of polymer particles with required properties.

Influence of polymeric non-ionic surfactants on the surface tension of styrene and on the styrene polymerization process

Dynamic surface tension of non-ionic surfactants pluronic F-168 and poly(dimethylsiloxan) bis(hydroxyalkyl) terminated (PDS) were studied using the drop profile analysis tensiometry. The comparison of these data with those from styrene heterophase polymerization studies show that only in the PDS:pluronic mixing ratio range between 1:0.2 and 1:0.8 the contribution of each surfactant component manifests its effect and provides appropriate conditions for the synthesis of polymer particles with required properties.

Synthesis of polymer particles with specific lysozyme recognition sites by a molecular imprinting technique

AbstractTo prepare silica beads covered with a lysozyme‐imprinted polymer layer, we polymerized acrylamide and acrylic acid or acrylamide and N,N‐dimethylaminopropylacrylamide with (NH4)2S2O8 in a phosphate buffer containing the lysozyme, surface‐modified silica beads, and crosslinkers; the result was the formation of a polymer layer with a lysozyme recognition site on the silica‐bead surface. By quantitative analysis of the supernatant of the solution containing the silica beads, we confirmed that modified silica beads, in contrast to unmodified silica beads, can selectively adsorb lysozymes. The process of binding and releasing the lysozyme to and from the modified silica beads can be repeated several times without degradation of the rebinding ability. A quartz‐crystal microbalance sensor fabricated with a molecularly imprinted polymer layer with a lysozyme recognition site was prepared. When a lysozyme aqueous solution was added to the solution in which the sensor was immersed, a high level of sensitivity and response was observed. High selectivity was also demonstrated by tests with other protein solutions. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3378–3387, 2001

Synthesis of polymer particles with specific binding sites for lysozyme by a molecular imprinting technique and its application to a quartz crystal microbalance sensor.

特定のタンパク質を認識捕そくし,穏和な刺激によりそのタンパク質を放出する分離担体を開発するために,分子インプリンティング法を応用してリゾチームに対して認識能を持つ高分子微粒子の合成を水溶液中で行った。アクリル酸,アクリルアミドからなるリゾチームの鋳型を有する高分子微粒子は,アクリル酸含有量が特定量のとき,リゾチームの鋳型を持たない高分子微粒子に比べ,リゾチームを選択的に認識することができた。また,鋳型を有する高分子微粒子へのリゾチーム吸着,脱着を数回繰り返しても,その認識は変化しなかった。鋳型高分子の利用例として,水晶振動子法を用いたセンサーの試作を行った。リゾチームの鋳型を有する高分子を表面に持つ水晶振動子をセルにセットし,リゾチーム水溶液を一定量ずつ滴下したところ,良好な感度と応答性を示し,センサー膜として十分利用できることが分かった。

Molecular Imprinting: Synthesis of Polymer Particles with Antibody-like Binding Characteristics for Glucose Oxidase

A phosphate buffer containing a mixture of glucose oxidase, acrylic acid derivatives, N,N′-1,2 dihydroxy-ethylene-bis(acrylamide), N,N′-(methylene)-bisacrylamide and surface-modified silica was radically polymerized with (NH4)2S2O8. The polymer formed a thin layer around the silica beads. After sieving of these polymer particles, the surface bound protein was eluted. In rebinding assays and enzyme activity tests a specific binding capacity for glucose oxidase of up to 0.557 μg GOD/100 mg dry weight of polymer particles could be determined. These polymer particles have the potential to be used as specific separation or dectection material.