BASF Polystyrene

BASF BASF Polystyrene Luran High impact polystyrene (HIPS) Styrene-acrylonitrile copolymer... 

Manufacturers and trade names BASF Polystyrene and Polystyrol, Dow Chemical Trycite , Styron Styron . 

Figure 2,53 Stress vs. strain at various temperatures for BASF Polystyrene 158 K—general purpose, heat resistant PS resin.

Figure 2.57 Stress-strain curves of high impact BASF Polystyrene resin at various test temperatures [6],...

Figure 2.58 Tensile modulus vs. temperature for two BASF Polystyrene resins.

Figure 2.65 Specific volume as a function of temperature and pressure (PVT diagram) for BASF Polystyrene 454 C— impact resistant PS resin.

New copolymerization methods, additives, rubber modification, and blending have made of polystyrene polymer and copolymers versatile packaging materials. Developed in 1930 by BASF, polystyrene (PS) is commonly produced by the continuous bulk polymerization of styrene in the presence of ethylbezene that control product viscosity and heat transfer. PS is hydrophobic, nonhygroscopic, and easily processed by extrusion and thermoform-ing. Three types of PS are available general-purpose, impact PS, and foams. 

In 1930 BASF, then part of IG Farhen, installed a plant for producing 100 tonnes of polystyrene per annum and in 1933 the first injection moulded articles were produced. In the US semi-plant-scale work at the Dow Chemical Company showed promise of commercial success in 1934. As a consequence there became available shortly before World War II a material of particular interest because of its good electrical insulation characteristics hut otherwise considerably inferior to the polystyrene available today. Because of these excellent electrical characteristics prices were paid of the order of several dollars per pound for these polymers. 

The market for SAN has remained small relative to that for polystyrene and ABS (discussed in the next section) and is probably only about 5% that of the latter. Major producers are BASF, Dow, Monsanto and Montedison. 

Report 85 Ring Opening Polymerisation, N. Spassky, Universite Pierre et Marie Curie. Report 112 Polystyrene - Synthesis, Production and Applications, J.R. Wunsch, BASF AG. 

Report 112 Polystyrene - Synthesis, Production and Applications, J.R. Wiinsch, BASF AG. 

Just as Herman Mark was an important initiator of the scientific development of polymer chemistry and physics in our century and has left his decisive stamp on it, so did he have a particular influence on the early phase of the scientific and industrial development of styrene monomer and polystyrene. In 1980, polystyrene can look back on 50 years of industrial production, which began at the end of 1930 at Badische Anilin- Soda-Fabrik (now BASF) in Ludwigshafen. 

It was possible to cover additional applications with these new types. In 1951 BASF found it was possible to impregnate polystyrene direct with expanding agents in the suspension process. This opened up great new possibilities for polystyrene foam (STYR0P0R, BASF, 33), for example in the packaging and building fields. 

Union Carbide (34) and in particular Dow adopted the continuous mass polymerization process. Credit goes to Dow (35) for improving the old BASF process in such a way that good quality impact-resistant polystyrenes became accessible. The result was that impact-resistant polystyrene outstripped unmodified crystal polystyrene. Today, some 60% of polystyrene is of the impact-resistant type. The technical improvement involved numerous details it was necessary to learn how to handle highly viscous polymer melts, how to construct reactors for optimum removal of the reaction heat, how to remove residual monomer and solvents, and how to convey and meter melts and mix them with auxiliaries (antioxidants, antistatics, mold-release agents and colorants). All this was necessary to obtain not only an efficiently operating process but also uniform quality products differentiated to meet the requirements of various fields of application. In the meantime this process has attained technical maturity over the years it has been modified a number of times (Shell in 1966 (36), BASF in 1968 (37), Granada Plastics in 1970 (38) and Monsanto in 1975 (39)) but the basic concept has been retained. 

STYR0P0R, BASF - polymerization of styrene monomer in suspension in the presence of pentane as the blowing agent. Manufacture of new insulating packaging materials, etc. Suspension polymerization of crystal polystyrene in Ludwigshafen. 

The solutions from a sample of anionic polystyrene (courtesy of BASF, Ludwigshafen) and the solvent were prepared by weighing. Polystyrene is characterized by the data in Table I. [The average molecular weights were determined in the Central Laboratory of the N.V. Staats-mijnen/DSM (Geleen, The Netherlands).]... 

In a process related to RAFT, BASF workers have shown that 1,1-diphenylethylene will control the molecular weight of PMMA and polystyrene, and permit block polymer synthesis [92]. They propose that radical chain ends add to the diphenylethylene to form a stable diphenylalkyl radical that does not add more monomer but can reverse to diphenylethylene and the same radical chain end for addition of more monomer. The diphenylalkyl radical cap has the additional possibility of forming a reversible dimer (Scheme 35). 

BASF is a chemical manufacturing company that operates production facilities in 38 countries, owns 159 subsidiaries and serves customers in more than 170 countries. Around 22% of BASF sales are made to North American industries. The firm operates in five business segments chemicals plastics performance products agricultural products and nutrition and oil and gas. The chemicals segment manufactures over 1,500 inorganic, petrochemical and intermediate chemicals for the pharmaceutical, construction, textile and automotive industries. The plastics segment primarily manufactures polystyrene, styrenics and... 

Hahn, K. Ehrmann, G. Ruch, J. et al. Synergistic flame-proof mixtures for polystyrene foams, PCT Patent Application, to Basf AG, WO/2006/007996, 2006. 

Dietzen, F.J. Gluck, G. Ehrmann, G. et al. Flame-proofed polystyrene foamed materials, PCT US Patent 6420442 assigned to Basf AG, 2002. 

Low monomer content PS materials are commercially available with specified styrene monomer levels of 150 ppm (mg/kg) that have actual contents of 100 ppm (ex. BASF O suffix materials 168 NO, 143 IO). These materials can be used for injection molding or extrusion and are priced above normal styrene monomer content materials (those where styrene < 500 mg/kg). High impact polystyrene copolymer materials (HIPS) use normal monomer level polystyrene since there has been no commercial market for such materials. 

Experiments were performed using toluene (Merck, purity > 99.5%), cyclohexane (Fluka, purity >99.5%), naphthalene (Merck, purity >99%), polystyrene (BASF, Mw = 101000 g/mol, Mn = 93000 g/mol) and carbon dioxide (Linde, technical grade, purity > 99.5%). The solvents were dried over molecular sieves. The water content was checked with Karl Fischer analysis. All other materials were used as received. 

Figure 1.4 Photograph of Herman F. Mark taken in 1936. Mark worked at I. G. Farben Industries in Germany for 6 years, from 1927 to 1932, and played a major role in the industrial development of styrene monomer and polystyrene (courtesy of BASF, Lud-wigshafen)...

Figure 1.8 Early photograph (ca 1948) showing some of the earliest polystyrene foam (Styropor ). Foamed polystyrene has unrivalled low-density and thermal insulating properties (courtesy of BASF, Ludwigshafen)...

Figure 1.10 Polystyrene foam rapidly became the packaging material of choice for everything from medical instruments to engines (courtesy of BASF, Ludwigs-hafen)...

Other chemical companies have also designed their own continuous process to produce high-impact polystyrene (HIPS), such as the Dow process, which consists of three elongated reactors in series (US Patent 2727 884, 1955) the BASF process, which consists of a prepolymerization CSTR followed by cascade of three CSTRs (US Patent 3 658 946, 1972) the Shell process, which consists of three CSTRs followed by a plug flow reactor (US Patent 4011 284, 1977) and the Monsanto process, which consists of a CSTR followed by a horizontal plug flow reactor (US Patent 3 903 202, 1975). 

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