Plastics conventional

Staudinger, J. J. P. The effect of cross-linking in vinyl-polymer resins in P. Morgan Plastics Progress Papers and Discussions at the Brit. Plastics Convention 1951, 13. London Iliffe Sons 1951. 

Fatty esters of sorbitan are commercially available as "Span" surfactants and have many applications. A common industrial route for the production of the Span esters is based on a two-step procedure, with acid-catalyzed sorbitol cyclization to sorbitan, followed by high-temperature alkali-catalyzed transeslerification. Alternatively, the cyclization and esterification can be conducted exclusively with acid catalysts, resulting in the isosorbide dicstcr, which can be applied as plasticizer. Conventional catalysts include p-TsOH and a sulfonic acid resin. 

The prime product is the steel, which is magnetically separated and then cleaned. The mixed non-ferrous metals are cleaned and resold. The residue is fluff, in light or heavy fractions, made up of glass, fabrics, rubber, lubricants and miscellaneous dirt as well as plastics. Conventionally, both categories of fluff have ended up as landfill. The systems as designed therefore make no provision whatever for the recovery of polymeric material. Meanwhile the mountains of fluff accumulate (see Fig. 8.2). 

Horsley, R. A. British Plastics Convention, London, llth-17th July, 1957... 

Nowadays, the most important tool to evaluate the environmental impact of a bioplastic and/or of a petroleum-based plastic (conventional plastic) is the LCA that determines the overall impact of a plastic on the environment by defining... 

Epoxy adhesives wet and bond to almost all surfaces and can be used with virtually any combination of metals, glass, ceramic, or plastic. Conventional solders only wet certain metals. Other surfaces, such as silicon or alumina or tantalum oxide, cannot be soldered without gold plating or other costly surface modifications. 

For the production of composites, it is normally desired that textiles used for reinforcement possess great tensile strength and an extreme stiffness. The Young s modulus of textiles has to be significantly higher than that of the matrices used (for example, plastics). Conventional warp-knitted fabrics cannot fulfill these demands. Therefore, weft-reinforced, warp-knitted fabrics (Fig. 8.3) were developed to increase the stiffness of warp-knitted fabrics. 

The first example refers to the detection of a 1mm side drilled hole at a depth of 45 mm in a polyethylene plastic material. Due to the high sound absorption in plastics, a low operating frequency is chosen. A probe having a 1 MHz element of 24 mm diameter was selected for this example. The echo pattern of a conventional probe with a PZT transducer is pre-... 

The acoustical device component is placed in water and is configured like a conventional impulse echo equipment. The ultrasound wave passed the delay path and enters the specimen container through a very thin plastic window. The backside of the container is a steel plate and will also be used as a reference reflector to measure pn. 

AH the common monobasic (107) and dibasic esters (108) of tetrahydrofurfuryl alcohol have been prepared by conventional techniques the dibasic esters and some of the mono esters are effective as primary or secondary plasticizers for vinyl polymers. Tetrahydrofurfuryl acrylate [2399-48-6] and methacrjiate [2455-24-5] specialty monomers, have been produced by carbonylation (nickel carbonyl and acetylene) of the alcohol (109) as weU as by direct esterification (110—112) and ester interchange (111). 

Containers. Aerosol containers, made to withstand a certain amount of pressure, vary in both size and materials of constmction. They are manufactured from tin-plated steel, aluminum, and glass. The most popular aerosol container is the three-piece tin-plated steel container. Glass containers, which are usually plastic coated, generally have thicker walls than conventional glass jars. They are limited to a maximum size of 120 mL and are used for pharmaceutical and cosmetic aerosols. 

In the examination of works of art on paper, the variations in density are often too small to be revealed by conventional x-radiography. Instead, much benefit has been derived from beta-radiography, where the P-radiation is provided by an extended radioisotope source, typically a sheet of plastic in... 

Injection Molding. Matched metal molds are used in the fabrication of plastic closures, specialty packages, and botde preforms. In conventional injection mol ding the plastic resin is melted in an extmder which forces a measured quantity or shot into a precision-machined chilled mold after which the nozzle of the extmder is withdrawn. 

Thermoforming. Thermoforming is the most common method of fabricating sheet into three-dimensional packaging. In conventional thermoforming, the sheet is heated to its softening point or just below the melting temperature. The softened plastic is forced by differential air pressure into an open-top mold to assume the shape of the female mold. The mold is chilled and the plastic sheet solidifies and is then removed from the mold. 

The food industry uses stainless steel tubing or piping extensively for moving food products conventional steel, cast iron, copper, plastic, glass (qv), aluminum, and other alloys are used for utilities. 

Because of its low melting point and high chemical stabiHty, HDPE is easily processed by most conventional techniques (94—98) specialized techniques have also been described (99—107) (see Plastics processing). 

A composite dmm is constmcted of a plastic, semirigid inner liner (usually polyethylene) and either a steel or fiber outer container or overpack. The composite dmm may be a useful compromise between a plastic dmm and a conventional steel dmm. It is strong enough to be handled like a steel dmm, yet provides an enclosure for chemicals that cannot be shipped safely in steel or fiber dmms. Capacities of composite dmms are 19—208 L (5—55 gal). Such dmms are used in chemical, pharmaceutical, and food industries. 

Plastic. A plastic bag usuaUy consists of a single heavy waU of plastic film, woven sheets of plastic tape, or laminates. Principal materials of constmction are polyethylene and polypropylene (see Fibers, olefin). Both transparent and opaque sheeting are used, and printabUity usuaUy is exceUent. Plastic bags can be fiUed and closed with conventional equipment beat-sealing is essential for open-mouthed bags to effect a moisture barrier. 

Fluoroplastics. Conventional plasticizers are used as processing aids for duoroplastics up to a level of 25% plasticizer. However, certain grades of Kel-E (chlorotriduorethylene) contain up to 25 wt % plasticizer to improve elongation and increase softness the plasticizers used are usually low molecular weight oily chloroethylene polymers (5). 

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