Polycarbonate moldings

Monoethano1 amine-containing formulations can be used to make polycarbonate molds with good dyeabiUty and crack resistance (186). 

Molding. The Hquid tempered chocolate is deposited into a metal or plastic (polycarbonate) mold in the shape of the final product. There are three basic types of mol ding soHd (or block), sheU, and hoUow. 

D. Wittmann, H. Peters, J. Schoeps, H.-J. Kress, J. Buekers, and K.-H. Ott, Flame-retardant, high-impact polycarbonate molding compounds, US Patent 5 061745, assigned to Bayer Aktiengesellschaft (Leverkusen, DE), October 29,1991. 

E. Wenz, T. Eckel, O. Meincke, H. Warth, and H. Eichenauer, Polycarbonate molding compositions with improved hydrolysis resis-... 

Beetle. [BIP Chem. Ltd.] Urea-fcamalde-hyde, nylon 6 and 66 compds., PET, PBT, unsat polyester, tx polycarbonate molding compds. 

Monoethanolamine-containing formulations can be used to make polycarbonate molds with good dyeabihty and crack resistance (186). Monoethanolamine, diethanolamine, and triethanolamine have been cited in formulations for epoxy resins compounds (187—192). 

Commercially available bisphenol A polycarbonate (molding, extrusion grade-from General Electric Co.,... 

Ebert, W., Kaufmann, R., Schwemler, C., Haese, W., Fischer, R, Dobler, M., Genz, J., Polycarbonate molding compounds with good demolding properties and moldings therefrom (2001). 

These copolymers, containing a high level of ITR, have also been commercialized in a highly weather-resistant film that has the appearance of a paint film. The film is available in transparent and opaque colors. In addition, the film can be made with a metallic look. The film can be used with in-mold-decoration (IMD) (see the section Processing Polycarbonates ) molding processes to produce class A automotive exterior parts. Because the film contains very high levels of the ITR resin, it has an excellent balance of scratch resistance, weatherability, chemical resistance, and thermal performance. 

Modifier for improved polycarbonate moldings W. Germany 2,304,894 1974 Bayer A.G. 

Therefore the polycondensates workgroup within the Bayer Central Research Department started several projects regarding polyheterocycles in the second half of the 1980s. First, work was focused on polypyrrole, particularly for antistatic layers on thermoplastics like polycarbonate (molded parts or sheets). " After less than two years, the Bayer workgroup was forced to terminate these activities by the intrinsic drawbacks of polypyrrole, like toxicity and high vapor pressure of the monomer, and the intense color and poor transparency of polypyrrole layers itself. 

This analytical technique has been applied to polycarbonate moldings (see Figure 5). Here the exothermic peak reaches a maximum at a Tf/Tg ratio of 1.3. It has also been applied to vacuum-formed ABS refrigerator door liners (see Figure 6). Here the peak reaches a maximum at a T//Tg ratio of 1.15 to 1.18. 

Since incomplete replication has been attributed to trapped air in the mold [4, 8], a vacuum system was used to quickly remove the air from the cavity of the mold when the mold closed. Figure 2 shows the effect of vacuum on the replication of nanofeatures for the 45D TPU. These results indicate that the use of vacuum can assist in enhancing the replication. Similar results were observed for polycarbonate molded with silicon tooling [6]. These... 

Polycarbonate acrylonitrile-butadiene-styrene alloy Allyl-diglycol- carbonate polymer Diallyl phthalate molding Cellulose acetate Cellulose-acetate-butyrate resin... 

In general, polycarbonate resins have fair chemical resistance to aqueous solutions of acids or bases, as well as to fats and oils. Chemical attack by amines or ammonium hydroxide occurs, however, and aUphatic and aromatic hydrocarbons promote crazing of stressed molded samples. Eor these reasons, care must be exercised in the choice of solvents for painting and coating operations. Eor sheet appHcations, polycarbonate is commonly coated with a sihcone—sihcate hardcoat which provides abrasion resistance as well as increased solvent resistance. Coated films are also available. 

The major use of 4-cumylphenol is as a chain terminator for polycarbonates. Its use in place of phenol gives a polycarbonate with superior properties (33). Eor a low molecular weight polycarbonate used for injection-molding appHcations, the use of 4-cumylphenol as a chain terminator significantly lowers the volatiHty of the resin. Other uses of 4-cumylphenol include the production of phenoHc resins, some of which have appHcations in the electronics industry (34). Another appHcation of 4-cumylphenol involves its reaction with ethylene oxide to form a specialty surfactant. 

Monofunctional, cyclohexylamine is used as a polyamide polymerization chain terminator to control polymer molecular weight. 3,3,5-Trimethylcyclohexylamines ate usehil fuel additives, corrosion inhibitors, and biocides (50). Dicyclohexylamine has direct uses as a solvent for cephalosporin antibiotic production, as a corrosion inhibitor, and as a fuel oil additive, in addition to serving as an organic intermediate. Cycloahphatic tertiary amines are used as urethane catalysts (72). Dimethylcyclohexylarnine (DMCHA) is marketed by Air Products as POLYCAT 8 for pour-in-place rigid insulating foam. Methyldicyclohexylamine is POLYCAT 12 used for flexible slabstock and molded foam. DM CHA is also sold as a fuel oil additive, which acts as an antioxidant. StericaHy hindered secondary cycloahphatic amines, specifically dicyclohexylamine, effectively catalyze polycarbonate polymerization (73). 

Multiblock Copolymers. Replacement of conventional vulcanized mbber is the main appHcation for the polar polyurethane, polyester, and polyamide block copolymers. Like styrenic block copolymers, they can be molded or extmded using equipment designed for processing thermoplastics. Melt temperatures during processing are between 175 and 225°C, and predrying is requited scrap is reusable. They are mostiy used as essentially pure materials, although some work on blends with various thermoplastics such as plasticized and unplasticized PVC and also ABS and polycarbonate (14,18,67—69) has been reported. Plasticizers intended for use with PVC have also been blended with polyester block copolymers (67). 

In a molded polymer blend, the surface morphology results from variations in composition between the surface and the bulk. Static SIMS was used to semiquan-titatively provide information on the surface chemistry on a polycarbonate (PC)/polybutylene terephthalate (PBT) blend. Samples of pure PC, pure PBT, and PC/PBT blends of known composition were prepared and analyzed using static SIMS. Fn ment peaks characteristic of the PC and PBT materials were identified. By measuring the SIMS intensities of these characteristic peaks from the PC/PBT blends, a typical working curve between secondary ion intensity and polymer blend composition was determined. A static SIMS analysis of the extruded surface of a blended polymer was performed. The peak intensities could then be compared with the known samples in the working curve to provide information about the relative amounts of PC and PBT on the actual surface. 

In this section, we examine fibrillation behavior of a polycarbonate (PC)-TLCP blend by injection molding. 

In general, properties of polyether sulfones are similar to those of polycarbonates, but they can be used at higher temperatures. Figure 12-6 shows the maximum use temperature for several thermoplastics. Aromatic polyether sulfones can be extruded into thin films and foil and injection molded into various objects that need high-temperature stability. 

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