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1. Microfluidic-supported emulsion polymerization: molecular weight and concentration of surface-capping agents impact the formation of anisotropic polyvinylmethacrylate particles

   https://doi.org/10.1039/D5PY00334B  

   Visaveliya, Nikunjkumar R; Kelestemur, Seda; Khatoon, Firdaus; Xu, Jin; Leo, Kelvin; McCoy, Karisma; St_Peter, Lauren; Chan, Christopher; Mikhailova, Tatiana; Bexheti, Visar; et al (January 2025, Polymer Chemistry)

   Surface-capping agents—for example, amphiphilic surfactant molecules, water-soluble polymers, or polyelectrolytes—play a critical role during polymerization reactions for both the formation and stability of colloidal polymer particles. 

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2. Ab Initio Emulsion Atom‐Transfer Radical Polymerization

   https://doi.org/10.1002/anie.201804647  

   Lorandi, Francesca; Wang, Yi; Fantin, Marco; Matyjaszewski, Krzysztof (May 2018, Angewandte Chemie International Edition)

   Abstract Stable latexes of poly(meth)acrylates with predetermined molecular weights, narrow molecular‐weight distributions, and controlled architecture were prepared by true ab initio emulsion atom‐transfer radical polymerization. Water‐soluble (macro)initiators in combination with a hydrophilic catalyst, Cu/tris(2‐pyridylmethyl)amine, initiated the polymerization in the aqueous phase. The catalyst strongly interacted with the surfactant sodium dodecyl sulfate (SDS), thereby tuning the polymerization within nucleated hydrophobic polymer particles. Long‐term stable latexes were obtained, even with SDS loading below 3 wt % relative to monomer. Block and gradient copolymers were prepared in situ. The reaction volume and solid content were successfully increased to 100 mL and 40 vol %, respectively, thus suggesting facile scale‐up of this technique. The proposed setup could be integrated in existing industrial plants used for emulsion polymerization. 

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3. Thermodynamics and morphology of linear multiblock copolymers at homopolymer interfaces

   https://doi.org/10.1063/5.0170650  

   Collanton, Ryan P.; Ellison, Christopher J.; Dorfman, Kevin D. (November 2023, The Journal of Chemical Physics)

   Block copolymers at homopolymer interfaces are poised to play a critical role in the compatibilization of mixed plastic waste, an area of growing importance as the rate of plastic accumulation rapidly increases. Using molecular dynamics simulations of Kremer–Grest polymer chains, we have investigated how the number of blocks and block degree of polymerization in a linear multiblock copolymer impacts the interface thermodynamics of strongly segregated homopolymer blends, which is key to effective compatibilization. The second virial coefficient reveals that interface thermodynamics are more sensitive to block degree of polymerization than to the number of blocks. Moreover, we identify a strong correlation between surface pressure (reduction of interfacial tension) and the spatial uniformity of block junctions on the interface, yielding a morphological framework for interpreting the role of compatibilizer architecture (number of blocks) and block degree of polymerization. These results imply that, especially at high interfacial loading, the choice of architecture of a linear multiblock copolymer compatibilizing surfactant does not greatly affect the modification of interfacial tension. 

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4. Polyamide nanofiltration membrane with highly uniform sub-nanometre pores for sub-1 Å precision separation

   https://doi.org/10.1038/s41467-020-15771-2  

   Liang, Yuanzhe; Zhu, Yuzhang; Liu, Cheng; Lee, Kueir-Rarn; Hung, Wei-Song; Wang, Zhenyi; Li, Youyong; Elimelech, Menachem; Jin, Jian; Lin, Shihong (April 2020, Nature Communications)

   Abstract Separating molecules or ions with sub-Angstrom scale precision is important but technically challenging. Achieving such a precise separation using membranes requires Angstrom scale pores with a high level of pore size uniformity. Herein, we demonstrate that precise solute-solute separation can be achieved using polyamide membranes formed via surfactant-assembly regulated interfacial polymerization (SARIP). The dynamic, self-assembled network of surfactants facilitates faster and more homogeneous diffusion of amine monomers across the water/hexane interface during interfacial polymerization, thereby forming a polyamide active layer with more uniform sub-nanometre pores compared to those formed via conventional interfacial polymerization. The polyamide membrane formed by SARIP exhibits highly size-dependent sieving of solutes, yielding a step-wise transition from low rejection to near-perfect rejection over a solute size range smaller than half Angstrom. SARIP represents an approach for the scalable fabrication of ultra-selective membranes with uniform nanopores for precise separation of ions and small solutes. 

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5. Tracking nucleic acid nanocapsule assembly, cellular uptake and disassembly using a novel fluorescently labeled surfactant

   https://doi.org/10.1039/D0RA09472B  

   Arifuzzaman, Md; Hartmann, Alyssa K.; Rouge, Jessica L. (November 2020, RSC Advances)

   null (Ed.)

   Intracellular trafficking and delivery of nucleic acids is an area of growing interest, particularly as it relates to therapeutic applications. Spectroscopic methods have been used to observe and quantitatively measure the delivery of oligonucleotides both in vitro and in vivo . Herein we demonstrate the use of a new fluorophore labeled surfactant presenting a solvatochromatic chromophore for tracking the assembly and degradation of a hybrid biomaterial we refer to as a nucleic acid nanocapsule (NAN). We show that the surfactant enables critical micelle concentration determination, monitoring of NAN disassembly in vitro , and the ability to track the cellular movement and activity of surfactant–oligonucleotide conjugates in cells when coupled with quantitative PCR analysis. 

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