Engineering-grade polymers

Additives for the Modification of Poly(Ethylene Terephthalate) to Produce Engineering-Grade Polymers... 

Hygroscopic polymers. On the other hand, most engineering-grade polymers have a chemical nature that causes them to attract and absorb moisture from the surrounding ambient air. Most engineering polymers are hygroscopic polymers. 

Polyethylene terephthalate (PET) an amorphous polymer is available in an engineering grade. It is extensively used in beverage bottles and films. 

Uses Color and m.w. stabilizer, antioxidant, melt flow aid for polymer processing (polyolefins, polyesters, elastomers, styrenics, engineering thermoplastics), adhesives, coatings antioxidant, UV stabilizer for polyolefins, food-grade polymers Regulatory FDA 21CFR 178.2010 Manuf./Distrib. Aldrich http //www.sigma-aidrich.com, GE Spec. http //www.ge.com/speciaitychemicais Trade Name Synonyms AO-2 f[Ciba Spec. Chems./Plastic Addit. http //www.cibasc.com]-, Doverphos S-680 [Dover http //www.doverchem.com]-, Doverphos S-686, S-687 t[Dover... 

Precaution Combustible Uses Antioxidant for elastomers, polyolefins, polyesters, cellulosics, resins, food-grade polymers, food-pkg. adhesives, petroleum oil, and waxes antioxidant and antiwear agent for motor oils, aviation piston engine oils, industrial oils... 

Moisture can accumulate on the surface of any plastic material, and some polymers actually absorb moisture into the pellet itself. Materials that absorb moisture—usually engineering-grade materials like nylon or polycarbonate—are called hygroscopic. Those that do not have the same attraction or affinity for moisture, and do not absorb it, are called nonhygroscopic polymers. They include commodity polymers such as polyolefins. 

J. D. Minford, Adhesive joining aluminum to engineering plastics II. engineering grade styrene and crosslinked styrene, in Physicochemical Aspects of Polymer Surfaces (K. L. Mittal, ed.), Vol. 2, p. 1161, Plenum Press, New York (1983). 

Increasingly, more engineering-grade plastic materials are being made available to the thermoforming processes. They allow manufacturers to match the physical properties of the polymer to the application. With these materials, new challenges to decorating thermoformed plastic parts are introduced, because their respective surface properties can be very dissimilar. 

Uses Permanent Internal antistat for thermoplastic film, molded prods., food-grade polymers temporary external antistat Improves pigment dispersibility and gloss rec. for PS, rubber-modified PS, ABS, flexible and rigid PVC, PE, engineering resins... 

Small amounts of polymer-grade terephthaHc acid and dimethyl terephthalate are used as polymer raw materials for a variety of appHcations, eg, adhesives and coatings. They are also used to make high performance polymers or engineering resins. Poly(ethylene terephthalate) is itself an engineering resin, although one more widely used is poly (butylene) terephthalate, formed by reaction with 1,4-butanediol as the comonomer. 

Good electrical insulation properties with exceptional tracking resistance for an engineering thermoplastic and, in particular, for an aromatic polymer. In tracking resistance most grades are generally superior to most grades of polycarbonates, modified PPOs, PPS and the polyetherimides. 

Polyester, thermoplastic TP polyesters have different grades. Polybutylene tereph-thalate (PBT) a crystalline polymer and an excellent engineering material. It has marginal chemical resistance but resists moisture, creep, fire, fats, and oils. Molded items are hard, bright colored, and retain their impact strength at temperatures as low as — 40°F (-40°C). Uses include auto louvers, under-the-hood electricals, and mechanical parts. 

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