Polypropylene commercial applications

Swiss Roll Cell This cell has been developed in Switzerland [89]. A commercial application is one oxidation step at a NiOOH anode in alkaline solution for the vitamin C production [22]. Mesh electrodes of stainless steel (cathode 1) and nickel (anode 3) are rolled up together with spacers of polypropylene mesh (2,4) on the central current feeder (5) and mounted in a cylinder (cells up to 1 m diameter, 200 m active area). The electrolyte streams axially through the cell. 

The design of the first commercial modules has allowed the commercial application of membrane contactors for some specific operations. This is the case of the Membrana-Charlotte Company (USA) that developed the LiquiCel modules, equipped with polypropylene hollow fibers, for the water deoxygenation for the semiconductor industry. LiquiCel modules have been also applied to the bubble-free carbonation of Pepsi, in the bottling plant of West Virginia [18], and to the concentrations of fruit and vegetable juices in an osmotic distillation pilot plant at Melbourne [19]. Other commercial applications of LiquiCel are the dissolved-gases removal from water, the decarbonation and nitrogenation in breweries, and the ammonia removal from wastewater [20]. 

Interest in the susceptibility of polypropylene (PP) to degradation, especially by heat, light, oxygen and combinations of these agencies, has kept pace with the increasing commercial application of this material. The purely photo (1-5) and thermal reactions (0 which occur, have been studied in isolation from one another, and it is clear that similar radicals are involved as intermediates in the overall processes. Previous work on acrylate and methacrylate polymers and copolymers (7-8) has demonstrated that the superficial differences in overall degradation mechanism may be attributed to the different ways in which the same primarily produced radicals react in the solid and liquid... 

Numerous examples of possible packing materials that allow bacterial immobilization exist, examples include both natural materials as soil [105], lava rock [18,50], expanded clay [94,97], sand [95,98], natural fibers [102] and aquifer material [106] and synthetic materials as perlite [53,107,108], granular activated carbon (GAC) [26,38,100,101], glass beads or rings [96] and polypropylene [18,107], apart from many commercial applications. 

Polypropylene is synthesized by polymerization of propylene, which may result in two main types of PP with commercial applications ... 

Generally, nanomaterials as flame retardants do not have commercial applications. Data obtained are commonly recognized as preliminary, and they are described here just as preliminary as well. One more example of such data is a study of heat release and char formation (in per cent units) at burning of polypropylene filled with magnesium hydroxide (5 pm, 1 pm particles, and nanoparticles) (Table 14.9). 

The development of polypropylene copolymer multiphase systems is continuing at a robust pace. These polymer systems, based on simple and inexpensive polymer budding blocks, are being improved for applications historically reserved for more expensive engineering thermoplastics. The understanding of the structure/property relationships in polypropylene copolymers will indeed be a driver for further innovation in the commercial application of these polymers. 

Membrane contactors can be made out of flat sheet membranes, which have some commercial applications. However, the most common commercial membrane contactors are made from small-diameter microporous hollow-fiber (or capillary) membranes with fine pores that run from the inner surface to the outer surface of the hollow-fiber wall. The contactor resembles a tube-in-shell configuration with inlet-outlet ports for the shell side and tube side. These kinds of membranes are typically made of hydrophobic materials such as polypropylene (PP), polyethylene (PE), polytetrafluoroethylene (PTFE), poly(tetrafluoroethylene-co-perfluorovinylether) (PEA), or polyvinylidene fluoride (PVDE). The membrane in a contactor acts as a passive barrier and as a means of bringing two immiscible fluid phases, such as gas and liquid or an aqueous liquid and an organic liquid, into contact with each other... 

Typically, a 50/50 blend of nitrile rubber and polypropylene is melt mixed with 5 % maleated PP and 1 % ATBN respectively and then cured with SnCl2 (0.5 %). The resistance to hot oil swell (72 h, 100 °C) of NBR/PP blend was found to be significantly better than that of EPDM/PP blend. Typical properties of the commercial dynamically cured NBR/PP TPV (Geolast ) are compared with other PP-based TPVs in Table 19.16. Commercial applications for this TPV were targeted for automotive seals and gaskets in the oil, fuel, and brake systems. However, this blend has not been as commercially successful as the Santoprene -type PP/EPDM-based TPV. 

Adjustable breathability is an area where responsive barriers have already found commercial applications. For example, a thermoresponsive breathable membrane using shape memory polyurethane has been developed by Mitsubishi Heavy Industries (SMP Technologies Inc., 2010). It can be laminated onto various types of textiles to provide waterproof, windproof yet breathable clothing. Another strategy based on a temperature-activated breathable monolithic film sandwiched between two layers of spunbond microfibrous polypropylene has been used by Ahlstrom Corp. to develop medical gowns that combine protection against virases with comfort and breathabUity (Rodie, 2005). 

However, the production of all-organic fibers from ICPs is still complicated and expensive. Several attempts have been made to obtain conductive fibers from ICPs such as polyaniline, PEDOT PSS, and pure PEDOT with conductivity values from 150 to 250 S/cm [22,23]. However, due to poor mechanical strength, microscale size, a low production rate, brittleness, and difficult processing, useful commercial applications are stiU limited. On the other hand, combination of other textile materials with ICPs could enhance their application areas. It could be done in two ways, either by mixing ICPs with insulating polymers such as polypropylene, polyethylene, and polystyrene, or by coating conventional textiles with ICPs. The coating method is explained in the next section. 

High toughness, good impact performance, and low cost make polyolefins such as polyethylene (PE) and polypropylene (PP) promising polymers to toughen PLA for commercial applications (e.g., packaging applications) [3-5]. However, the immiscibility of polyolefin/PLA blends due to differences in their chemical strucmres generally results in weak interfacial adhesion (indicated by poor dispersion, a very broad size distribution, and distinct particle interfaces) and poor mechanical properties [5, 7]. 

Basic correlations between metallocene struetures and polymer properties have been identified [13], eliminating the drawbacks of early metalloeene eatalyst generations. For instance, substantially increased molecular weights, that are of interest for commercial applications of polypropylenes, are obtained when a methyl substituent is introduced in the 2-position of... 

Bend made the composite that composed of PF and wood flour (WF). The first commercial application of this composite was used as a gearshift knob for Rolls Royce car in 1916 under the registered trademark of Bakelite [1]. On the contrary, thermoplastics can be repeatedly melted without any change in their inherent properties, including polypropylene (PP), high and low density polyethylene (HOPE and LDPE), polyvinyl chloride (PVC), and so on. In this chapter, the abbreviation of WPCs represents wood-thermoplastic composites, which are usually simply referred to as wood-plastic composites (WPCs). Similarly, the common understanding of plastics always refers to thermoplastics. 

Chirality. Another microstructural area of exceeding importance in chain-reaction polymerizations is the chiral forms of homopolymers produced during polymerizations of 1-olefins three carbons in length and longer. Polypropylene is probably the most ubiquitous commercial chain-reaction homopoljnmer where differences in repeat unit chiralities produce products that vary widely in their commercial applications. Various levels of homopoljnmer crystallinity related to chiral differences create homopolymers that range in applications from adhesives to automotive to health care products. 

Two other derivatives that have received attention are thermoplastic NR (TPNR) blends and epoxidized NR (ENR). TPNRs often are blends of NR with polypropylene [15], Applications include automotive components and floor tiles. ENR-50, with 50 mol% epoxidized double bonds, can be used where oil resistance or air impermeability is needed together with high strength [16], Some applications include hoses and seals. The grafting of methyl methacrylate on NR has been carried out on a commercial scale by polymerizing the monomer in a rubber latex. The primary use of the grafted material is as an additive to improve flow of unmodified rubber. 

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