Effect of the particle size of the solid protective agent tricalcium phosphate and its in‐situ formation on the particle size of suspension polystyrene

Abstract

In this study, the effect of the particle size of solid protective agent, commercially obtained and in-situ formed tricalcium phosphate (TCP), on the particle size of suspension polymerized polystyrene (PS) is investigated. It is concluded that when a solid protective agent like TCP is used, its particle size and distribution plays an important role in both suspension stability and particle size of the PS obtained. As the particle size of the TCP becomes smaller, the particle size of the PS obtained is reduced in line with it. In situ precipitation of TCP reduces its particle size considerably. Therefore, to produce PS with the same particle size, lesser amount of in-situ precipitated TCP is required which gives way to production recipe savings and cleaner PS products. ZUSAMMENFASSUNG:Der EinfluD der TeilchengroRe eines festen Suspendiermittels (handelsiibliches oder in-situ gebildetes Tricalciumphosphat (TCP)) bei der Suspensionspolymerisation von Polystyrol (PS) auf dessen Teilchengrdlje wurde untersucht. Aus den Ergebnissen wird geschlossen, daR TeilchengroRe und TeilchengrORenverteilung des festen Suspendiermittels die Stabilitat der Suspension und die TeilchengroRe des PS beeinflussen. Parallel zur Verringerung der TeilchengroRe des TCP nimmt auch die des PS ab. Die Teilchen-groBe von in-situ-ausgefalltem TCP ist erheblich kleiner als die von handelsiiblichem TCP, weshalb sich mit einer geringeren Menge von in-situ-ausgefalltem TCP PS mit der gleichen TeilchengroRe wie bei Verwendung von handelsiiblichem TCP herstellen 1aRt. Dadurch ergeben sich Einsparungen bei der Produktion und reinere Produkte.

Influence of the geometric factors of the experimental device used in suspension polymerization on the properties of poly(styrene‐co‐divinylbenzene) microparticles

“…The particle size distributions (PSDs), determined by laser diffraction, of some of the experiments can be observed in Figure 4, which depicts the relative volume frequency of each microparticle size. The PSDs curves show that the particle size of the microparticles obtained is generally smaller than 100 μm, as stated previously, which is a lower mean size than that reported by other authors who used TCP as a suspension agent 43–45. From the PSD curves, the values of d 50 and of span can be calculated, and they are given in Tables III and VI.…”

“…The PSDs curves show that the particle size of the microparticles obtained is generally smaller than 100 lm, as stated previously, which is a lower mean size than that reported by other authors who used TCP as a suspension agent. [43][44][45] From the PSD curves, the values of d 50 and of span can be calculated, and they are given in Tables III and VI. In general, the PSD of the microparticles obtained are bimodal. This is very usual in immiscible liquidliquid systems when the value of the dispersed phase concentration is over 15% vol 26,46,47 and when the coalescence is negligible owing to the use of a sufficiently high concentration of surface-active agents.…”

Structural modification of expandable polystyrene. I. Copolymerization with α‐methylstyrene

“…In this field, the fundamental effect of agitation has been studied by several investigators 16–21. The suspending agent can also affect the particle size and distribution of the product 22–24…”

Suspension Polymerization of Styrene with Pickering Emulsifiers

“…We investigated the free-radical polymerization of styrene in the presence of hydroxyapatite or calcium carbonate as dispersants and sodium dodecylbenzenesulfonate (NaDDBS) or poly(vinylpyrrolidone) (PVP) as surfactants. They are used in various papers (ref., [7][8][9][10][11][12] NaDDBS) and in some patents (ref., [16 -19] PVP) as modulation agents for hydroxyapatite.…”