Engineering resins polycarbonate

Polymers are long-chain molecules composed of repeated smaller units called monomers. The term polymer spans an enormous spectrum of substances that find widespread use in virtually all aspects of modern society. Polymers range from high-volume commodity types (polyethylene, polystyrene, etc. ), to synthetic fibers (polyesters, polyamides, etc.), to engineering resins (polycarbonates, polyacetals, etc.), and beyond. 

Common examples of toughened engineering resins include polycarbonate and polyesters. Unlike most other engineering resins, polycarbonate has some miscibiH-ty with PM MA, and traditional core-shell modifiers can significantly enhance the impact performance (Fig. 14-12). 

Fig. 1. Engineering resins cost vs annual volume (11) (HDT, °C) A, polyetheretherketone (288) B, polyamideimide (>270) C, polyarylether sulfone (170- >200) D, polyimide (190) E, amorphous nylons (124) F, poly(phenylene sulfide) (>260) G, polyarylates (170) H, crystalline nylons (90—220) I, polycarbonate (130) J, midrange poly(phenylene oxide) alloy (107—150) K, polyphthalate esters (180—260) and L, acetal resins (110—140).

Engineering resins can be combined with either other engineering resins or commodity resins. Some commercially successhil blends of engineering resins with other engineering resins include poly(butylene terephthalate)—poly(ethylene terephthalate), polycarbonate—poly(butylene terephthalate), polycarbonate—poly(ethylene terephthalate), polysulfone—poly (ethylene terephthalate), and poly(phenylene oxide)—nylon. Commercial blends of engineering resins with other resins include modified poly(butylene terephthalate), polycarbonate—ABS, polycarbonate—styrene maleic anhydride, poly(phenylene oxide)—polystyrene, and nylon—polyethylene. 

What properties of polycarbonate allow it to be classified as an engineering resin ... 

Engineers like to design machines that take plastics and inject them into molds, extrude them into filament, sheets, rods, and film, or blow-mold them into shapes. They want these plastics to have a terrific balance of mechanical, electrical, and chemical properties. That s why they have attached their name to engineering resins, a set of plastics unlike thermosets that they can remelt and further process mechanically. Nylon, polycarbonates, and polyesters are the three most popular engineering resins. 

Engineering resins are polymers designed to excel in. certain physical characteristics. For the most part they are thermoplastics, but they can be thermosets as well. Examples are Nylon 6, Nylon 66, polycarbonates, and polyesters. Phenolics can be considered engineering resins. 

While carbon fiber (thickness on the order of 1000 nm) composites offer very strong materials, carbon nanotubes make even stronger composites. These carbon nanotubes have aspect ratios of over 1000 (ratio of length to diameter). Further, because some carbon nanotubes are electrically conductive, composites containing them can be made to be conductive. A number of carbon nanotube matrixes have been made including using a number of engineering resins, such as polyesters, nylons, polycarbonates, and PPE. 

Core-shell emulsion polymers with a core or rubbery stage based on homopolymers or copolymers of butadiene are used as impact modifiers in matrix polymers, such as ABS, for styrene acrylonitrile copolymer methyl methacrylate (MMA) polymers, poly(vinyl chloride) (PVC), and in various engineering resins such as polycarbonate) (PC) poly(ester)s, or poly(styrene)s, further in thermosetting resins such as epoxies. 

The 1950s gave rise to the polypropylenes and polycarbonates. Other engineering resins such as Polyetheretherketone (PEEK) and polysulfones were developed later. 

Polycarbonate resins are important engineering thermoplastics with good mechanical and optical properties as well as electrical and heat resistance, useful for many engineering applications. Polycarbonates have been commercially produced by the interfacial polycondensation between a bisphenol-A salt in an aqueous caustic solution and phosgene in an organic solution as follows [reaction (13)] ... 

Batch injection molding machine thermoplastics commodity resins, polyolefins (LDPE, HDPE, PP), styrenics (PS, PMMA. polycarbonates, ABS, PET), and engineered resins for higher impact strength. Continuous extruder thermoplastics. Casting PP fine film 10 to 50 pm cast film 100 to 400 pm thermoformable sheet 200 to 2500 pm. Film blow LDPE, HDPE, PP. Pug mill clay materials for bricks, tiles, and ceramics. 

The general motivation for blending styrenic resins with other polymers, particularly with the higher priced engineering resins, such as polycarbonate or polyphenylene ether, is primarily to lower the cost and improve the processability of the latter resins. As far as styrenic resins are concerned, some of the reasons for blending stem from the need to improve their property deficiencies, viz. solvent resistance, impact strength, heat resistance and flame resistance. 

Although polycarbonate is exceptional among engineering resins in exhibiting an outstanding level of toughness, its ductile-brittle transition depends on the temperature, notch sharpness, sample thickness and thermal aging effects. A sharp ductile-brittle transition [Carhart, 1985] for polycarbonate occurs at 0-10°C, hence its... 

PPE/HIPS blends filled the price-performance gap between the styrenic resins (HIPS, ABS) and the engineering resins such as polycarbonate, polyarylate and polysulfones. The technology and applications of PPE/HIPS blends have already been discussed under the styrenic resin blends section (Table 15.3). 

Modification of Engineering Resins Specific interaction of the phosphonium ionomer from Exxpro elastomer with selected engineering resins such as Polycarbonates(PC), Polyesters(PET), Polyacrylates(PAE), Polyamides(PA), Polyphenylene Oxide(PPO), and Acetals(PAc) can be utilized to compatibilize, impact modify or nucleate the above resin in blends with similar polymers. Typical examples are ... 

MAJOR APPLICATIONS Automotive, business machine, and electrical/electronics industries. PPO is mainly used to manufacture blends with high-impact polystyrene (HIPS). PPO/nylon, PPO/PBT, and PPO/polyolefin blends are also available on the mcuket. PPO based materials rank first in terms of total consumption among blends based on engineering resins such as nylon, polycarbonate (PC), polyacetal, and reinforced terephthalate polyesters (PET and PBT).( ... 

Of the 1-7 Mt of phenol produced in the U.S.A. in 1983, 34% went into phenol-formaldehyde resins (for plywood adhesives), 15% to caprolactam and 5% to aniline. However, an increasing proportion (presently 35%) is being converted into bisphenol A , the basis for polycarbonate glazing and high-performance engineering resins " ... 

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