Regular Polymeric Microspheres with Highly Developed Internal Structure and Remarkable Thermal Stability

Abstract

In this study, the synthesis and characterization of permanently porous polymeric microspheres was presented. The microspheres were obtained via suspension polymerization using diverse functional monomers, such as 4,4′-bis(methacryloyloxymethylphenyl)sulphone, 1,4-bis(methacryloyloxymethyl)benzene, 4,4′-bis(methacryloyloxymethylphenyl)methane, N-vinylpyrrolidone, ethylene glycol dimethacrylate, and divinylbenzene as a co-monomer. As porogenic solvents, toluene and chlorobenzene were applied. The main aim of the research was to synthesize polymers having a highly developed internal structure and a good thermal stability. The synthesized materials were characterized by ATR-FTIR, scanning electron microscopy, a size distribution analysis, a low-temperature nitrogen adsorption–desorption method, differential scanning calorimetry, and thermogravimetry coupled with FTIR and inverse gas chromatography. It was found that, depending on the functional monomer, regular microspheres with a specific surface area in the range of 418–746 m2/g can be successfully synthesized. Moreover, all the synthesized copolymers showed a good thermal stability. In helium, they exhibited 5% mass losses at temperatures over 300 °C, whereas in air these values were only slightly lower. In addition, the presence of miscellaneous functional groups promoted diverse kinds of interactions. Therefore, the microspheres can be possibly use in many adsorption techniques including high temperature processes.

Synthesis and Characterization of Polymeric Microspheres Template for a Homogeneous and Porous Monolith

“…Microspheres, also known as microparticles, are either microcapsule or monolithic particles containing small spherical particles with sizes ranging from 1 to 1000 µm [16][17][18]. There are three classes of pores that can be distinguished: micropores (linear dimension below 2 nm), mesopores (dimension 2-50 nm), and macropores (dimension above 50 nm) [19]. Polymeric microspheres offer good control of particle size and attract biotechnological interest due to their pore interconnectivity, low mass density, and high surface area [20].…”

Rheological Behavior of Phase Change Slurries for Thermal Energy Applications

“…Latex dispersions with a broad particle size distribution have been shown to exhibit lower degrees of shear-thinning, while narrow distributions are linked to higher degrees of shear-thinning . The width of the distribution is characterized by the span . In the studied fluids, PCS A, B, and C have average spans of 3.1, 5, and 3, respectively.…”

“…46 The width of the distribution is characterized by the span. 47 In the studied fluids, PCS A, B, and C have average spans of 3.1, 5, and 3, respectively. Hence, a higher degree of shear-thinning is expected in the PCS A and PCS C samples, compared to PCS B with a wider distribution, as seen in Figure 2, and represented by the significantly wider span compared to PCS B.…”

Porous Polymers Based on 9,10-Bis(methacryloyloxymethyl)anthracene—Towards Synthesis and Characterization

“…In our previous studies [ 52 ], we used quite a high amount of PVA to prevent of agglomeration of the synthesized microspheres and obtain a required diameter of the final beads. However, this approach led to some problems with the entire removal of the stabilizer from the porous surface of the product.…”

“…In our approach, we targeted into polymeric microspheres with considerably developed porous structure, diversified functional group and high thermal stability. As indicated in our previous study [ 52 ] synthesis of porous copolymers based on aromatic divinylbenzene (DVB) with different comonomers leads to materials with a good thermal resistance. For all synthesized materials, the T 5% determined in helium atmosphere was above 300 °C: Following this strategy, we used a tetrafunctional methacrylate monomer based on anthracene, i.e., 9,10-bis(methacryloyloxymethyl)anthracene (BMA).…”