polypropylene

(redirected from Polypro)
Also found in: Dictionary, Thesaurus.
Related to Polypro: polypropylene

polypropylene

(pŏl'ēprō`pəlēn), plasticplastic,
any organic material with the ability to flow into a desired shape when heat and pressure are applied to it and to retain the shape when they are withdrawn. Composition and Types of Plastic
..... Click the link for more information.
 noted for its light weight, being less dense than water; it is a polymerpolymer
, chemical compound with high molecular weight consisting of a number of structural units linked together by covalent bonds (see chemical bond). The simple molecules that may become structural units are themselves called monomers; two monomers combine to form a dimer,
..... Click the link for more information.
 of propylene. It resists moisture, oils, and solvents. Since its melting point is 121°C; (250°F;), it is used in the manufacture of objects that are sterilized in the course of their use. Polypropylene is also used to make textiles, ropes that float, packaging material, and luggage.

Polypropylene

A common flexible plastic usually spun into fiber for rope and woven goods.

Polypropylene

 

a thermoplastic polymer of propylene, [—CH2—CH(CH3)—]n; a colorlesscrystalline substance of iso-tactic structure. Molecular weight M̅w, 300,000–700,000; maximum crystallinity, 73–75 percent; density, 0.92–0.93 g/cm3 at 20°C; melting point, 172°C. Polypropylene has high impact strength (impact strength, notched 5–12 kilojoules per sq m, or kilograms-force · cm per sq cm), high resistance to multiple bending, and low vapor and gas permeability; its durability is comparable to that of the polyamides.

Polypropylene is a good dielectric (power factor, 0.0003–0.0005 at 1 megahertz) and a poor heat conductor. It is insoluble in organic solvents and resistant to boiling water and alkalies, but darkens and decomposes under the influence of HNO3, H2SO4, and chromium mixtures. Since polypropylene has low heat and light resistance, special additives called polymer stabilizers are introduced into the mixture.

Polypropylene is produced by solution or bulk polymerization of a monomer. It is processed by injection molding and extrusion. Polypropylene is used to manufacture fibers and films that retain their ductility at 100°-130°C, as well as expanded plastics, machine parts, shaped products, pipes (for aggressive liquids), various fittings, containers, and household goods.

The amorphous phase, in a 3–7 percent quantity formed during polypropylene synthesis, is isolated from the basic crystalline product and used in the manufacture of rubber household goods and additives for lubricating and motor oils. Polypropylene is produced in the USSR, Italy (Moplen), Great Britain (Propa-thene), the Federal Republic of Germany (Hostalen), and the USA (Poly-pro, Pro-fax). The 1973 world production of polypropylene was estimated at 2.4 million tons.

REFERENCES

See references under .

O. N. PIROGOV

polypropylene

[‚päl·ə′prō·pə‚lēn]
(organic chemistry)
(C3H6)x A crystalline, thermoplastic resin made by the polymerization of propylene, C3H6; the product is hard and tough, resists moisture, oils, and solvents, and withstands temperatures up to 170°C; used to make molded articles, fibers, film, rope, printing plates, and toys.

polypropylene

A plastic polymer of propylene; a tough material having good resistance to heat and chemical action.
References in periodicals archive ?
Currently, the line sits in a "U" shape, with the Ska depalletizer at the head of the U, and the Roberts PolyPro can handle applicator at the terminus.
Three of Robert PolyPro's most in demand applicators will be featured at Pack Expo: the single bottle handle applicator rated at up to 30 bottles per minute; the new to Pack Expo craft brew and mobile canning can handle applicator for up to 10 cases per minute; and the robotic bottle-handle applicator rated from 30 to 60 cases per minute, depending on the model.
Like polypro, polyester is made by extruding melted plastic resins through a ale to create rain thread like fibres.
Offered this year only by Fox, Isolwool resists odor, is three times more abrasion-resistant than merino alone, dries 25% faster, and eliminates the smell of polypro. Made for strenuous outdoor activities, it comes in lightweight quarter-crew and crew lengths for hiking, and medium and heavyweight versions for mountaineering, snowboarding, and cross-country skiing.
A US district court ruled that CUNO's PolyPro XL and LifeAssure filters infringe two Pall patents covering its ULTIPLEAT line of filters.
According to these renovators, polypro hollow-braid rope is inexpensive and easy to form into loops to make the "chains."
District Court for the Eastern district of New York ruled that Cuno's PolyPro XL and LifeAssure filters infringe on two Pall patents.
That first night I sleep in my sweat pants, polypro top, and socks.
The group consists of Aero R-722, a low-smoke and low-heat release sheet product for the aerospace industry; CamAlloy, a TPO or ABS material intended for outdoor recreation markets; CastAlloy, a cast acrylic and thermoplastic composite targeted at the spa, bath, and shower, and display areas; Exstreem PolyPro, for fiberglass and metal replacement; and PackAlloy RP rollstock, comprising recycled materials.
Among Sun Chemical's other new products developed in 2000 were PolyPro inks for milk cartons, HydroTense 2000 corrugated flexo inks, RotoMax 2 gravure laminating ink, and SunSlip heatset silicon alternative for binder applications.
Roberts PolyPro Inc., 5416 Wyoming Ave., Charlotte, NC 28273.
* Church & Dwight Co., Inc., enlisted the aid of Roberts PolyPro, Charlotte, NC, in redesigning its Arm & Hammer carpet deodorizer package.