Commercial products, radiation

Ethylene oxide treatment can also be considered as an alternative to radiation sterilizahon in the commercial production of disposable medical devices (Chapter 21). These techniques do not, however, offer the same degree of sterility assuranee as heat methods and are generally reserved for temperature-sensihve items. 

Aqueous systems have been studied by a very large number of investigators. Economy, safety, convenience and quality of product have combined to make this the method of choice for commercial production of copolymers. The industrial importance of such end products as elastomers and acrylic fibers has been a special incentive to related fundamental studies. Furthermore, the relatively high solubility of acrylonitrile monomer in water coupled with insolubility of the polymer make it a convenient test monomer for studies of initiation by redox systems (6, 25, 102). Large numbers of homogeneous chemical initiators and some heterogeneous initiators have been studied as well as initiation by photochemical means, by ultrasonics and by ionizing radiation. It will not be possible here to review the enormous world literature. Several publications (/, 92, 117) refer in some detail to the older papers, and we shall restrict our comments to recent interpretations that have received support from several quarters. 

Mimotopes has been involved in the development, use, and commercialization of radiation-grafted polymer surfaces for multiple parallel synthesis since the late 1980s.10-12 Although other workers have reported the use of radiation-graft polymers in solid-phase synthesis,13,14 as far as we are aware, the graft polymer devices manufactured and sold by Mimotopes (SynPhase Crowns, SynPhase Lanterns) are the only current commercial products of this type. These products are presented in Fig. 1. The SynPhase Lanterns are the current design for small molecule synthesis. The initial... 

Radiation Process. Commercial production of wood-polymer composites began in the mid 1960 s using the radiation process. 

Japan, and South America, and commercial amounts of wood-plastic flooring were produced for airport terminals and office buildings. Today there is no known commercial gamma radiation production of wood-plastics outside of the United States. 

The common feature of all black carbon constituents is the strong absorption within the whole solar spectrum. Black carbon particles are particularly toxic as pollutants on the other hand, they share the beneficial aspect of shielding efficiently harmful UV radiation. Although commercial products such as industrially produced carbon black, impure graphite and activated carbon differ chemically and morphologically from emitted organic aerosols, they are usually used as model particles for screening studies [56]. So far,... 

Treatment of solid wood over the years for increased utility included many chemical systems that affected the cell wall and filled the void spaces in the wood. Some of these treatments found commercial applications, while some remain laboratory curiosities. A brief description of the earlier treatments is given for heat-stabilized wood, phenol-formaldehyde-treated veneers, bulking of the cell wall with polyethylene glycol, ozone gas-phase treatment, ammonia liquid- and gas-phase treatment, and p- and y-radiation. Many of these treatments led to commercial products, such as Staybwood, Staypak, Im-preg, and Compreg. This chapter is concerned primarily with wood-polymer composites using vinyl monomers. Generally, wood-polymers imply bulk polymerization of a vinyl-type monomer in the void spaces of solid wood. 

Acrylic adhesives first appeared about 1937 the acrylic resins may be considered as belonging to the vinyl family [1, p. 305], Today, acrylic adhesives appear in many forms as both pressure-sensitive and non-pressure sensitive formulations in organic solvent and emulsion forms as monomer and polymer cements as anaerobics as cyanoacrylates as so-called reactive or honeymoon two-part systems and as radiation curing formulations. Commercial production of acrylic polymers began in the late 1920s, but it was not until 1958 that the first aerylie sealant was developed [10, p. 226]. The solvent-based acrylic sealants were first introdueed to the eonstruction industry in about 1960 ... 

Chemical and Electrochemical Corrosion of Pile Materials Under Radiation, Since uranium is readily oxidized, it must be protected from the water by a sheath or coating. Also, for the external cooling, a lining tube must be placed in the graphite. With water as the coolant, these two (the sheath and tube) must be of the same material or of two materials close together in the electrochemical series to suppress electrochemical corrosion. Of the few suitable materials, which have low danger coefficients and are not attacked appreciably by hot water, etc., the most promising are, in order, beryllium and aluminimn. While the former is more desirable also for its hardness and resistance to wear, the limited supply of beryllium available plus the lack of commercial development make aluminium with its more extensive commercial production and development practically the only alternative, imtil such time as beryllium or beryllium-aluminimn alloys can compete or surpass aluminium or unless further corrosion tests prohibit the use of aluminium and force the development of Be or Be-Al. 

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