PC/ABS (polycarbonate / acrylonitrile-butadiene-styrene terpolymer blend) is a thermoplastic alloy of polycarbonate and acrylonitrile-butadiene-styrene. Both of these materials are well known amorphous plastics. Alloying these two materials enhances processability, and provides non-halo flame retardancy.
Polycarbonate (PC) is a rigid thermoplastic that provides clarity, toughness, and good heat resistance. By itself, polycarbonate has reasonable resistance to burning, and that resistance can be increased by adding flame retardants that are typically halogen containing. Acrylonitrile-butadiene-styrene is a well know rigid thermoplastic that offers both moderate impact and moderate chemical resistance. The heat resistance of acrylonitrile-butadiene-styrene is lower than that of polycarbonate. Like polycarbonate, halogen containing additives are used to increase resistance to burning.
Most polymers tend to undergo a decrease in viscosity as shear rates are increased. That behavior allows modest increases in injection pressure to help fill injection molded parts. Since polycarbonate very gradually decreases in viscosity as shear rates are increased, it can be a challenge to process. While ABS is used in many applications, the usefulness of ABS is limited by medium heat resistance, and by medium impact performance. Flame retardant grades of both PC and ABS primarily use “halogen FR technology”, and use of that technology can limit applications. These limitations can be overcome by using compounding technology to produce PC/ABS alloys.
Unlike PC, alloys of PC and ABS do undergo a significant decrease in viscosity as shear rates are increased. This allows PC/ABS alloys to be processed much more easily that pure PC. These alloys are very tough materials. Although they are not as tough as PC alone, they are much tougher than ABS. They also have much higher heat resistance than pure ABS. A “non-halogen” flame retardant technology is used in FR PC/ABS blends. This expands the applications for this tough, moderate heat resistant, material.
Although Polymer Resources offers PC/ABS blends in a wide range of melt flows, we are always willing to produce products within a 5 unit sub-range to suit a customer’s specific needs. Please see the following data sheets:
Additives, Modifiers, and Reinforcing Agents:
Additives- UV stability, easy release (mold releases), colorants, and other stability additives
Flame retardants, impact modifiers, flow enhancers
Glass fibers, mineral fillers