Syndiotactic polystyrene: Process and applications

Abstract

ABSTRACT:In this review, a summary is provided of the manufacturing process for syndiotactic polystyrene together with an overview of applications of syndiotactic polystyrenes, including selected examples of typical applications. The manufacturing process of syndiotactic polystyrene, consists of several basic sections: catalyst premix preparation, monomer treatment, polymerization reaction using a powder bed reactor together with an evaporative cooling system, devolatilization and extrusion, and finally finishing, including cooling and crystallization of the strands. This process is suitable for providing a wide range of syndiotactic polystyrenes comprising homopolymers, with a broad range of melt flow rates as well as copolymers of various comonomer contents, leading to products with various melting temperatures. Essential relationships and correlations of the separate process stages are demonstrated, in addition to useful analytical methods to control the process. These polymers' unique combination of heat resistance, chemical resistance, and electrical properties has led to their successful application in automotive, electrical and electronics, consumer and industrial uses.

Olefin Polymerization with Half-Metallocene Catalysts

“…It is thus clear that these observed facts are significantly unique compared to those previously demonstarated in the copolymerization using ordinary metallocenes or linked half-titanocenes (Copolymerization with norbornene [86] Syndiotactic polystyrene (SPS) is a unique polymeric material due to its high melting point (T m =270°C), high crystallinity, low density, low dielectric constant, and high chemical resistance toward organic solvents [10,40,109,110, Example concerning syndiospecific styrene polymerization by half-titanocene complexborate catalyst [185][186][187]). This polymer cannot be prepared by free radical, anionic or ordinary Ziegler-Natta processes, but can be prepared by the syndiospecific polymerization using various half-titanocenes (Scheme 2.10), Cp'TiX 3 or Cp'TiX 2 (Y) (Cp' = cyclopentadienyl group; X = halogen, alkoxo, alkyl etc.…”

“…This polymer cannot be prepared by free radical, anionic or ordinary Ziegler-Natta processes, but can be prepared by the syndiospecific polymerization using various half-titanocenes (Scheme 2.10), Cp'TiX 3 or Cp'TiX 2 (Y) (Cp' = cyclopentadienyl group; X = halogen, alkoxo, alkyl etc. ; Y = anionic donor ligand) [10]. Ethylene/styrene co-polymers, which cannot be prepared by conventional (free radical, Ziegler-Natta) processes [10, See Reviews for linked half-titanocenes [16,41,42,[188][189][190]), also attract considerable attention [191][192][193], because styrene incorporation into the PE backbone results in drastic changes in the viscoelastic behavior as well as in the thermomechanical properties of the polymeric material [192].…”

Novel cycloaurated gold(III) complexes and their effects on styrene polymerization

“…When gold complexes added to the reaction media s-PS was formed ( Fig. 2; Table 1; run nos., [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] After these results were evaluated, series of experiments were conducted at room temperature with different solvents and results. Bulk polymerization was carried out at different catalyst concentrations but conversion did not pass 25% yield.…”

“…The first commercial s-PS plant worldwide at a capacity of about 36,000 t/year in Schkopau, Germany opened in 1999, and continued by Idemitsu Kosan in a modernized production facility in Chiba, Japan, in 2006 [16]. In automotive systems, s-PS can be applied in power distribution centers under the hood, in electrical lighting, and electronics, s-PS can be used successfully for connectors, plugs and sockets, glass-fiber-reinforced and color-stabilized s-PS grades are materials for iron skirts and at least very promising markets of s-PS are food and water contact applications [17]. Especially half-metallocene transition metal complexes are very effective catalysts to synthesize s-PS [18,19].…”

Use of Online Spectroscopy to Control Polymerization in Industrial Processes

“…[27] This facility utilized a unique process specifically developed for the characteristics of styrene monomer and the SPS polymer which made traditional polymerization processes impractical. [28] The reactor is a fluidized powder bed with upflow mixing.…”