Styrenic polymers history

The history of styrenic polymers is documented by Amos (1) and Scheirs (2). The first patent of the suspension or bulk polymerization, respectively, of styrene in presence of rubbers goes back to the 1950s (3,4). 

Styrene acrylonitrile copolymer (SAN) copolymers have been commercially available since the 1940s. Due to their comparatively high price, initially they have been used in rather special applications. The history of styrenic polymers has been reviewed by various authors (1,2). 

The use of differential scanning calorimetry to identify secondary transitions in thermoplastics is studied. The temperature and breadth of the secondary transition are related to the those of the alpha transition in a variety of methacrylate, acrylate and styrene polymers, as well as polycarbonate. The effect of thermal history and the position and sharpness of these endothermic transitions is discussed. Some comparisons are made between this technique and results obtained via dielectric analysis and dynamic mechanical analysis obtained in the laboratory. 7 refs. 

SDS [Sulzer Dainippon Sumitomo] A continuous process for polymerizing styrene. The reactants are mixed in a static mixer, which gives a very uniform time/temperature history for the polymer. Developed jointly by Sulzer, Dainippon Ink Chemicals, and Sumotomo Heavy Industries. Offered for license in 1990. 

The development of high styrene content styrene-butadiene copolymers (SBCs), such as K-Resin SBC, is best thought of as a branch off the history of anionic polymerization and rubber. A number of excellent reviews cover this aspect of the subject in great detail, and should be obtained for detailed examination of the history of rubber and anionically synthesized rubber polymers [1-3]. What follows is a brief overview to fit the high styrene content SBC into a historical context. 

Rubber is one of the few examples where chemical synthesis succeeded in a nearly identical performance copy of a natural polymer (polyisoprene) - albeit with a completely different chemical composition (styrene-butadiene-rubber, SBR). Regarding sustainable development, the complete imbalance of the early rubber history has emanated during recent years into equilibrium between natural and synthetic rubber. 

Raman microimaging is used to estimate the effect of the siUca filler on phase separation in binary polymer blends composed of brominated poly(isobutylene-co-para-methyl) styrene (BIMS) and butyl rubber (HR). The domain sizes, relative concentration of polymer components within domains, and distribution of particulate silica filler and zinc stearate curative are characterised for blends of different compositions and history of ageing treatments. The presence of increased concentrations of precipitated silica results in better... 

Styrene and its polymers deserve a special place in polymer science history. The polymerization of a liquid obtained by Simon by the pyrolysis of storax in 1839 was the first recoiled polymerization of a vinyl monomer (1). Since he confused the polymer with an oxidation product, he called it styrene oxide. Blythe and Hofmann (2) suggested the name meta-styrol and Kopp (3) showed that this product and cinnanol, obtained by the distillation of cinnamic acid to be identical. Erlenmeyer (4) described this product as vinyl benzene. 

Another area in which both proton and carbon-13 nmr have proved very powerful is the determination of the structure of copolymers. This has a long history (ref. 6, Chap. X 15,16)9 beginning with the observations of butadiene-styrene copolymers in 1959, Again, the information content of the spectra has increased remarkably since these early reports. Although compositional sequence lengths and probabilities can be calculated from the copolymer equation using the traditional data of polymer composition vs. monomer feed composition, nmr allows direct measurement of the sequences and gives in addition much structural detail not available from overall composition alone. 

Escoubes M et al (1984) Ion clustering in styrene-based ionomers - calorimetric and gravimetric hydration studies and effect of ion concentration and thermal history. J Appl Polym Sd 29(4) 1249-1266... 

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