Polyolefins commercial production

Polypropylene Other Polyolefins Commercial Production Properties and Applications Consumption of Polyolefins New Monomers and Polymers Growth of Understanding Catalysts and Kinetics Structure vs. Properties The Future... 

A classification by chemical type is given ia Table 1. It does not attempt to be either rigorous or complete. Clearly, some materials could appear ia more than one of these classifications, eg, polyethylene waxes [9002-88 ] can be classified ia both synthetic waxes and polyolefins, and fiuorosihcones ia sihcones and fiuoropolymers. The broad classes of release materials available are given ia the chemical class column, the principal types ia the chemical subdivision column, and one or two important selections ia the specific examples column. Many commercial products are difficult to place ia any classification scheme. Some are of proprietary composition and many are mixtures. For example, metallic soaps are often used ia combination with hydrocarbon waxes to produce finely dispersed suspensions. Many products also contain formulating aids such as solvents, emulsifiers, and biocides. 

Polyolefins. The most common polyolefin used to prepare composites is polypropylene [9003-07-0] a commodity polymer that has been in commercial production for almost 40 years following its controlled polymerisation by Natta in 1954 (5). Natta used a Ziegler catalyst (6) consisting of titanium tetrachloride and an aluminum alkyl to produce isotactic polypropylene directly from propylene ... 

The Zr-FI catalyst selectively forms PE even in the presence of ethylene and 1-octene, while the Hf complex affords amorphous copolymers, resulting in the catalytic generation of PE- and poly(ethylene-c6>-l-octene)-based multiblock copolymers through a reversible chain transfer reaction mediated by R2Zn. The development of an FI catalyst with extremely high ethylene selectivity as well as a reversible chain transfer nature has made it possible to produce these unique polymers. Therefore, both Ti- and Zr-FI catalysts are at the forefront of the commercial production of polyolefinic block copolymers. 

Larger 3- and 4-m.e.v. Dynamitron electron beam accelerators are likewise available commercially. Service capabilities increase with the m.e.v. level of the electron beam accelerator. A 3.0-m.e.v. Dynamitron electron beam accelerator furnishes radiation capable of penetrating a maximum 370 mils of a unit density material or 185 mils of 2.0-density material other performance capabilities are doubled as well. The overwhelming majority of polyolefin plastic products now being manufactured have section thicknesses which can be penetrated safely even by a 1.5-m.e.v. electron beam accelerator. Two possible exceptions would be printed circuit board and thick-walled pipe. A 3-m.e.v. accelerator could readily meet such requirements. The performance capabilities of the 3-m.e.v. accelerator (12-ma. power supply) are increased not only with respect to maximum depth of penetration but also processing capability, which amounts to 14,000 megarad-pounds per hour at 50% absorption efficiency. 

The development of the gas-phase technology represents a major advance for the commercial production of polyolefins. A gas-phase process avoids the problem of the high cost remaining in the high-mileage slurry and solution processes (associated with recycling of diluent or solvent and drying of the polymer). 

The pyrolysis treatment of unclean polyolefin wastes may yield two commercial products ... 

Within the past five years, commercial interest in metallocene catalyst components for the polymerization of olefins has increased enormously. Commercial production of a rising number of polyolefin types from different companies is creating a burgeoning and highly diversified demand for metallocenes. New brand names (e. g., Metocene (Basell), Elite (Dow Chemical), Engage (DuPont), Exact (ExxonMobil), Luflexen (Basell), Apel (Mitsui Chemicals), Borecene (Borealis), Finathene (TotalFinaElf), Topas (Ticona), just to name a few) characterize polyolefins such as PE, elastomers, PP, cycloolefin copolymers (COCs) and PS from metallocene-type catalysts [1-3]. 

Very few CPs are produced in bulk quantities. Polyphenylene sulfide, a member of the third generation of polymers, was produced in bulk quantities many years before CPs were established and its dopability was elucidated. Polyethylenedioxythiophene is commercially available as a water-based colloidal dispersion (Baytron P water dispersion), and presumably as dispersible powders. The powders with a conductivity of 5-10 S/cm can be dispersed in thermoplastic polymers and in organic solvents such as xylene. Polyaniline doped with dodecylbenzene sulfonic acid and complexed with zinc dodecylbenzene sulfonate is commercially available as a powder, which can be dispersed in polyolefins. The same polymer doped with p-toluenesulfonic acid is also available as a dispersible powder, Ormecon, and in a predispersed form for solution processing in polar and nonpolar media. Based on Ormecon PANi, there are many commercial products marketed for many different applications. 

Technology for preparing nanocomposites directly via compounding has been investigated by Vaia, Ishii, and Giannelis. Industrial R D efforts have focused on process technology (e.g., melt or monomer exfoliation processes), as there are a number of polymers (e.g., polyolefins) that do not lend themselves to a monomer process. Nanocomposites with a variety of polymers, including polyacrylates or methacrylates, polystyrene, styrene-butadiene rubber, epoxy, polyester, and polyurethane, are amenable to the monomer process. The enhancement of mechanical properties, gas permeability resistance, and heat endurance are the primary objectives for the application of PCN, and their success will establish PCNs as a major commercial product. 

Since the discovery of olefin polymerization using the Ziegler-Natta eatalyst, polyolefin has become one of the most important polymers produeed industrially. In particular, polyethylene, polypropylene and ethylene-propylene copolymers have been widely used as commercial products. High resolution solution NMR has become the most powerful analytieal method used to investigate the microstructures of these polymers. It is well known that the tacticity and comonomer sequence distribution are important factors for determining the mechanical properties of these copolymers. Furthermore, information on polymer microstructures from the analysis of solution NMR has added to an understanding of the mechanism of polymerization. 

Hindered Amine Light Stabilizers (HALS) are a new class of highly efficient stabilizers protecting polyolefins and other polymers against light-induced deterioration. They were initially developed into commercial products in our laboratories. In this review we describe the details of how they were synthesized, evaluated and developed. 

The original, simplest polyolefins, polyethylene and polypropylene, continue to dominate the scene, even after two decades, to such an extent that no other polyolefin even appears on the production charts. Nevertheless, a great many (we may assume all) available olefins have been tested, and many have been found capable of being converted to stereoregular polymers. As was mentioned above, poly(l-butene) and poly(4-methy1-1-pentene) are being offered commercially and may be expected to achieve significant volume in the future. Isotactic and syndiotactic polystyrene are of much theoretical interest (26) but are not yet commercial products. 

The following two commercial products are typical examples (1) Alacstat C-2 (Alcolac Chemical Corp., U.S.A.). This is anN,N-bis(2-hydroxyethyl)-alkylamineused for polyolefins at 0.1% by weight. (2) Catanac 477 (American Cyanamid Co., U.S.A.). It is N-(3-dodecyloxy-2-hydroxypropyl)ethanolamine (C12H25OCH2CHOHCH2NHCH2CH2OH) used for linear polyethylene (0.15% by weight), for polystyrene (1.5% by weight), and for polypropylene (1% by weight). These compounds are not recommended for PVC. 

Commercial products include chlorinated polyolefins CP (Eastman) and Hardlen (Toyo Kasei Kogyo). 

There are two types of polyolefin paper at present polyethylene and polypropylene. Commercial products include the SWP polyolefin papers developed jointly by Mitsui Petrochemicals Inc. and Crown Zellerboch Co., and Pulpex and Perlosa paper products by Hercules Co. 

In considering antioxidants for aromatic polyesters, it should be remembered that most commercial products were originally developed for use in polyolefins and rubbers. Several points mnst be taken into account when selecting antioxidants for these polyesters ... 

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