Plastics. Also polypropylene

The pigments are used primarily in plastics, including polypropylene fibers, because of very good bleed resistance, heat stabiUty, and lightfastness. The reds also find use in printing inks, primarily for high quaUty products. 

These rubbers are now also being blended on a large scale with polyolefin plastics, particularly polypropylene, to produce a range of materials which at one extreme are tough plastics and at the other the so-called thermoplastic polyolefin rubbers (TPORs) (.see Section 11.9.1). 

CO sensor allows detection of CO in the presence of hydrocarbons and other adsorbable contaminants. The membrane Is usually chosen for Its ability to protect the sensing electrode. However, If It has low permeability to air, the sensor will have a slower response time. The electrolyte and counter electrode have also been reported as Influencing selectivity and device performance In the determination of hydrazines (5) and NO2 (9), respectively. Finally, materials of construction are typically Teflon and high-density plastics like polypropylene because such materials must be compatible with reactive gases and corrosive electrolytes. 

Figure 14.22 shows a line with examples of products. The basic plastic, usually polypropylene (PP) but also high-density polyethylene (PE-HD), and the additives required by the formulation (e. g coupling agent, UV stabilizer, pigment if required, antibacterial agent, or flame retardant), are added to the first barrel of the screw kneader by a gravimetric... 

Figure 9-7D. Typical efficient metal and porcelain support plate designs for gas injection into packing. Designs also available in plastic-FRP, polypropylene, PVC, etc. (Also see Figure 9-7F.) Used by permission of Norton Chemical Process Products Corp.

It is also important to prepare the sample container prior to sample storage. In the case of samples for metal analysis, the following procedure is recommended. The sample container, borosilicate glass or plastic (polyethylene, polypropylene or Teflon (PTFE)) should be treated in the following sequence ... 

Plastic lumber is recycled plastics processed such as commingled plastic, polyethylene plastic, and polypropylene plastic. To improve their performances different developments have been used such as specialty additives (lubricants, deoxidizers, etc.). An example is by adding as low as 10 wt% of short glass fiber to these recycled plastics can double their strength. Other fibers used include hemp, flax, and sisal. They are principally extruded other processes are used such as injection and compression molding, to produce products competitive to wood lumber on land and in the water. Compression molding allows for a deep-molded grain and a much more dense board. The density also helps the product resist moisture absorption and improves weatherability. 

A main line of development now is multi-functional additives, such as reinforcing fillers talc is added to polypropylene to improve stiffness and heat stability, pigments can aid in UV protection, plasticizers also function as lubricants and anti-static agents. A potentially fertile field is that of synergism between components, where better performance in vital properties such as weathering and flammability can be achieved by using lower concentrations of synergistic additives. 

Plastic materials have become basic and indispensable in our life. To protect against contamination and conserve them, food products are distributed in different plastic packages bags, bottles, boxes, etc. that contain all kinds of edible products liquid (water, milk, cold beverages) or solid (fruit, meat, fish, frozen foods, etc.). The group of commercial plastics, also termed commodity plastics, consists of the most used polymers in terms of volume and number of applications. They are mainly polystyrene (PS), polypropylene (PP), high-and low-density polyethylene (HDPE, LDPE), polyethylene terephthalate (PET) and, in lower proportion, polycarbonate (PC) [71. 

Nucleating agent, cell-control These agents promote symmetrical, cohesive expansion of cells within foamed polyurethane and polystyrene plastics also to a limited extent in polyethylene and polypropylene plastics. 

Polyolefin plastic Also called olefin, olefinic plastics or olefinic resins. They represent a very large class of carbon-chain TPs and elastomers. The most important are polyethylenes and polypropylenes. They all have extensive use in many different forms and applications. 

At primary refineries (whether thermal or electrolytic), silver and gold are valuable by-products. Copper is easUy removed from bullion and will normally be sold in matte or speisse form. Arsenic, antimony, tin, bismuth and some other minor metals may also arise as by-products at electrolytic refineries, but this is not widespread. Their removal is costly, and where a saleable by-product is not produced, they are considered penalty elements (see Appendix B for details of recent price trends in minor metal by-products). At secondary smelter/refineries the trend is similarly towards increased by-product recovery. As weU as antimony, the key materials here are plastic (or polypropylene), and less commonly sodium sulphate (for detergent manufacture). 

Polypropylene. Polypropylene (PP) is used ia packagiag appHcations as films and ia rigid containers. Battery cases could be considered another packagiag appHcation. Dead batteries are often collected at the poiat of sale of new batteries. In the U.S., some states have laws mandating this. Lead, acid, and plastics, particularly PP from battery casiags is recovered and recycled (3). Care must be taken to limit worker exposure to lead duting this process (44). PP is also recovered from bale wrap and other PP fabrics used for wrappiag ia the textile iadustry and from other containers (45). 

The electrowinning process developed by Ginatta (34) has been purchased by M.A. Industries (Atlanta, Georgia), and the process is available for licensing (qv). MA Industries have also developed a process to upgrade the polypropylene chips from the battery breaking operation to pellets for use by the plastics industry. Additionally, East Penn (Lyons Station, Pennsylvania), has developed a solvent-extraction process to purify the spent acid from lead—acid batteries and use the purified acid in battery production (35). 

The chelated organic titanates also function as adhesion promoters of the ink binder to printed substrates such as plastic films, paper, and aluminum foil (504). The acetylacetone complexes of titanium are the preferred products for promoting adhesion of printing inks to polypropylene films. 

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