A Useful Poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) Triblock Crosslinker in a Diffusion‐Controlled Polymerization Method

Monodisperse micron‐sized polystyrene particles crosslinked with a novel poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) triblock diol diacrylate (t‐BDDA) were produced via simple dispersion polymerization. It was established that the monomer‐diffusible surface characteristics of primary particles played a decisive role in producing the monodisperse crosslinked polymer particles. We named this concept a diffusion‐controlled polymerization method, DPM. Here in this study, particularly, t‐BDDA is proposed as a very useful crosslinker capable of self‐assembling and crosslinking in the process of particle formation and particle growth.     

Impact of microcellular plastics on industrial practice and academic research

Microcellular plastics (MCP) refer to any plastic with tiny bubbles of less than about 50 microns. It is made by subjecting polymers with a large amount of dissolved gas to a thermodynamic instability so as to nucleate a large number of cells instantaneously. MCP has been extruded and injection molded to make various industrial products. The fundamental theory for design of MCP and the processing methods are reviewed. It also discusses the design of equipment, including the die or mold, for MCP processing. The performance of MCP and the advantages of using MCP are presented. Some of industrial applications are also highlighted.     

Cyclic semiparallel Ricci tensor for harmonic curvature in the complex quadric

We introduce the notion of harmonic curvature for real hypersurfaces in the complex quadric $Q^m=S{O}_{m+2}/S{O}_{m}S{O}_2$. First, we prove that the unit normal vector field N on real hypersurfaces in $Q^m$ with harmonic curvature is singular, that is, $\mathfrak{A}$-principal or $\mathfrak{A}$-isotropic. Next by using a new notion of cyclic semiparallel Ricci tensor, we give a new result on real hypersurfaces with harmonic curvature and constant mean curvature in $Q^m=S{O}_{m+2}/S{O}_{m}S{O}_2$.