This article presents the results of investigations on heterophase polymerization of vinyl monomers in the presence of organosilicon compounds of different structures. On the basis of the detailed study of the kinetic and topochemical regularities of the heterophase polymerization of vinyl monomers, the conditions for the synthesis of polymer suspensions with a narrow particle-size distribution using a one-step method have been determined.
1 December 2024 in Russian Journal of Physical Chemistry A
The colloid-chemical properties of water-soluble and poorly soluble poly(ethylene oxide) and poly(propylene oxide) block copolymers (pluronics), as well as the rheological properties of interfacial adsorption layers (IALs) formed by them and the polymer generated during polymerization initiation on the particle surface, were studied. The temperature, surfactant concentration, and polymer effects on the effective elastic modulus, determined during the lateral deformation of IALs, were evaluated. The strongest interfacial layers are formed by the poorly water-soluble pluronic, which contains a hydrophilic polyoxyethylene block surrounded by two hydrophobic polyoxypropylene blocks. The high strength of the interfacial adsorption layer on the particle surface affords polymer suspensions with high (up to 33%) polymer contents and narrow particle size distributions.
A chimeric RNase A inhibitor (SUMO-RI) was produced by fusing a SUMO domain to the N-terminus of the murine Rnh1 protein. Functional assays demonstrated that SUMO-RI effectively protects RNA from RNase A-mediated degradation under conditions mimicking real-time RT-PCR, with performance comparable to that of commercial RNase inhibitors. The primary advantage of the chimeric design is its improved technological suitability: SUMO-RI exhibits markedly enhanced storage stability relative to the recombinant Rnh1 inhibitor. However, this benefit comes with a trade-off—SUMO fusion reduces thermostability at temperatures above approximately 47 °C. Together, these findings establish SUMO fusion as a rational engineering strategy for RNase inhibitors, offering improved practical handling at the expense of thermal resilience.