Synthesis and Characterization of Pressure and Temperature Dual‐Responsive Polystyrene Microbeads

Abstract

A facile approach to the synthesis of pressure and temperature dual‐responsive polystyrene (PS) microbeads with controlled sizes via dispersion polymerization is described. Three different luminophors are selected and directly introduced into the reaction system and thus incorporated into the resultant PS microbeads during polymerization. By manipulating the reaction conditions, including concentrations of the initiator and monomer, polarity of the reaction medium, and injection rate for the monomer, uniform PS microbeads with sizes ranging from 1 to 5 μm are obtained. When a light source centered at 365 nm is used to excite all the luminophors in the PS beads, three distinct and resolvable emission peaks corresponding well with the luminophors are observed. By taking advantage of their sensitive responses to both pressure and temperature, the PS beads can be utilized for quantitative measurements of these two stimulations simultaneously. The PS beads loaded with multiple luminophors have the ability to serve as building blocks for the fabrication of novel sensing and imaging devices and therefore provide a promising strategy for the study of aerodynamics.

Characterization of multi-dye pressure-sensitive microbeads

“…The range of response times at 90% rise time due to the shock wave spreads from 26 μs to 1582 μs. For reference, the response times of polystyrene microbeads (following previous procedures 25 are also included, which show that they are the largest response times, which is consistent with previous results. 1 The polystyrene and silica microbead response time comparison is also shown in Figure 4.…”

Luminescent two-color tracer particles for simultaneous velocity and temperature measurements in microfluidics

“…Furthermore, to the authors knowledge, other sensitivities of the luminescence intensity of either species to their chemical environment, such as pH value, have not been reported. Zhu et al (2013) synthesized pressure and temperature dual-responsive PS-particles using EuTTA as the temperature sensitive dye and Coumarin 6 as the reference dye. The authors found a large temperature dependency of EuTTA in the order of 2% − K −1 .…”

Study on morphology, molecular weight and thermal properties of composite microspheres prepared by controlling feeding ways and reaction time

“…With increase of the reaction time, an increase in the T d (by 6,9,13,13,14, and 17 8C, shown in Table III) is also observed. The results of GPC (Table II) indicate the enhanced thermal performance is not due to the increase of molecular weight.…”

“…[1][2][3] It is known that the performance of the polymer microspheres greatly lies on their morphology. 6,7 Among them, feeding ways and reaction time as significant factors have been investigated to obtain controllable morphology of polymer microspheres. 6,7 Among them, feeding ways and reaction time as significant factors have been investigated to obtain controllable morphology of polymer microspheres.…”

“…4,5 The diameter and morphology of the microspheres, in principle, are influenced by various process parameters, such as feeding ways, reaction time, stirring speed, concentration of surfactant, and temperature, and so forth. 6,7 Among them, feeding ways and reaction time as significant factors have been investigated to obtain controllable morphology of polymer microspheres. For instance, Thomas et al synthesized poly(methyl methacrylate) (PMMA) microspheres and indicated that reduction of the injection rate yielded uniform, small particles in the desired size range with a marked improvement in particle quality.…”