Styrenic plastics properties

Polystyrene [9003-53-6] (PS), the parent of the styrene plastics family, is a high molecular weight linear polymer which, for commercial uses, consists of - 1000 styrene units. Its chemical formula (1), where n = - 1000, tells htde of its properties. 

Stress-strain diagram, 27 721 Stress-strain instrument, 27 744 Stress-strain properties, of styrene plastics, 23 359-362... 

This study was therefore undertaken to prepare and evaluate acrylonitrile—butadiene-styrene (ABS) and methyl methacrylate-butadiene-styrene (MBS) polymers under similar conditions to determine whether replacement of acrylonitrile by methyl methacrylate could improve color stability during ultraviolet light aging, without detracting seriously from the good mechanical and thermal-mechanical properties of conventional ABS plastics. For purposes of control, the study also included briefer evaluation of commercial ABS, MBS, and acrylonitrile-butyl acrylate-styrene plastics. 

Additional opportunities in the styrene plastics industry exist for the development of products having such unique properties as high heat resistance and optical transparency. Arco produces the Dylark family of heat-resistant styrene plastics, which are copolymers of styrene-maleic anhydride. These products have a good balance of mechanical properties and have a heat distortion (under ASTM D68) of 234 F (33) which is markedly higher than homo polystyrene. 

Perhaps the best known member of the "heat-resistant" styrene plastics family is General Electric s Noryl (34). Noryl is an alloy of poly(phenylene oxide) and high-impact polystyrene. Heat deflection temperatures for Noryl range as high as 300 °F. The balance of mechanical properties is excellent, although processability is more difficult than for conventional styrene plastics. 

The styrene plastics industry has emerged over the past 30 years to become a major worldwide business. The industry has grown because the excellent balance of mechanical properties and processability of styrene plastics allow it to fill diverse market needs. The advent of workable industrial processes for both monomer and polymer and the fact that styrene plastics were made from once inexpensive raw materials have likewise contributed to the growth of the industry. In spite of the relative maturity of the science and the industry, styrene plastics remain a fruitful area for research. For example, the development of new materials having unique properties, such as fire and heat resistance, and the development of efficient energy and material-saving fabrication processes are expected to be the subject of extensive study in the future. 

Styrenic plastics such as acrylonitrile/butadiene/styrene graft copolymers (ABS) and impact-resistant polystyrenes are very sensitive towards oxidation, mainly because of their butadiene content. Degradation on weathering starts at the surface and results in rapid loss of mechanical properties... 

ABS nylon alloy A thermoplastic alloy of acrylonitrile-butadiene-styrene plastic (ABS) and nylon (PA) with properties similar to ABS but witb bigber elongation at yield. See acrylonitrile-butadiene-styrene plastic nylon plastic. 

Chem. Descrip. Dioctyl maleate CAS 2915-53-9 EINECS/ELINCS 220-835-6 Uses Comonomer used in polymerization with vinyl acetate, vinyl chloride, styrene and derivs. of acrylic and methacrylic acids used in latex paints, textiles as specialty plasticizer Properties APHA50 max. liq. m.w. 340 sp.gr. 0.939-0.944 vise. 9.1-9.5 cs (100 F) pour pt. -75 F acid no. 0.10 max. flash pt. (COC) 370 F ref. index 1.452-1.454 94% act. 

MABS is similar to ABS except for the addition of an additional monomer, usually methyl methacrylate. MABS is an amorphous, clear, transparent material with thermal and mechanical properties like ABS. The transparency is achieved by matching the refractive indices of the matrix resin (the transparent acrylate—acrylonitrile—styrene polymer) with the polybutadiene rubber impact modifier. MABS has the highest impact resistance of all the styrenic plastics. Sometimes called transparent... 

Figure 3.7 Fatigue properties of some styrene plastics...

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