Polymethyl methacrylate sphere

The viscosity of cross-linked polymethyl methacrylate spheres in benzene was measuredf and found to be... 

Nishimura et al. [9] measured interacting forces between a polymethyl methacrylate sphere and a flat plate, onto which expandable fluorine mica platelets (EM, Coop Chemical Co. Ltd., Tokyo) were coated. By using the AFM technique, Nishimura et al. [9] successfully measured the forces interacting in a NaCl aqueous solution between the PMMA probe and the EM-coated flat surfaces that apparently behaved as a macroscopic basal plane of EM. The data for forces obtained by the above technique were consistent with the forces theoretically calculated according to the DLVO theory. 

Bisphenol A (BPA) is a common compound used in the synthesis of many plastics and epoxy resins. However, recent studies have determined BP A is an emerging contaminant, which can disrupt the endocrine system and potentially cause cancer [115]. By molecular imprinting, Gao s group created numerous nanocavities in polymethyl methacrylate (PMMA) spheres, which can specifically target BPA (Fig. 37). The monodisperse PMMA spheres can be made into a CCA-based optical sensor. When the sensor is exposed to BPA solution, binding... 

Of course, it is impossible to find particles with zero adhesion to confirm the theoretical argument that spheres should form a face-centered cubic structure above 0.49 volume fraction. However, certain types of polymer latex can be made to approximate to the theoretical nonadhesion conditions above. Polymethyl methacrylate particles were polymerized in a dispersion and polymer molecules were grafted to the surface to provide a steep repulsive force on close approach. The solvent was chosen to reduce the van der Waals force to a low level, by matching the refractive index to the spheres, obtaining an almost transparent suspension from the milky preparation. 

These foams can be defined as composites consisting of hollow microspheres and a polymeric matrix. This one is made of a thermosetting (PU, PIR, PF, EP, silicone or unsaturated polyester) or of a thermoplastic (PE, PP, PVC, PS, polyimide) [56]. The microspheres can be made of silica, glass, carbon, ceramics or polymers such as PS, PE, PP, polyamide (PA), polymethyl methacrylate (PMMA), divinyl benzene (DVB)-maleic anhydride, and so on [56-58]. The diameter of the tiny hollow spheres is 300 mm or less [35]. They contain an inert gas such as nitrogen or a CFC. The properties of these syntactic foams depend on matrix type, microsphere type (and the contained gas), ratio matrix to microspheres, curing process, production technology. Syntactic foams can be made in combination with the conventional ones. Such a complex composite can be formnlated into a mouldable mass then shaped or pressed into cavities. 

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