Application of Radiation

They investigated the effect of radiation on tensile strength and elongation at break of EPDM/PP blend. Fresh and waste PPs were separately compounded with EPDM. In spite of the improvement in their gel content at 150 kGy, the degraded component causes alternation in mechanical properties. 

The effect of ionizing radiation on thermal oxidation of PP/EPDM blend over the range of total gamma doses up to 250 kGy was also studied by Zaharescu and 

The effect of ultrasonic irradiation on the mechanical property, morphology, and crystal structure of PP/EPDM blends were examined by Chen and Li (16). Appropriate ultrasonic intensity can increase the toughness of PP/EPDM blends noticeably. SEM showed that with ultrasonic irradiation, the morphology of a well-dispersed EPDM phase is formed in the PP/EPDM blend. Ultrasonic irradiation interestingly 

Zaharescu (17) studied the compatibility of PP/EPDM blends prepared by gamma irradiation. He found that the composition of polymer specimens does not influence the relative contribution of constituents to the calculated heat capacity Cp) values for tested blends exposed to the same dose. 

3 DYNAMICALLY VULCANIZED PP/EPDM BLENDS (OR THERMOPLASTIC VULCANIZATES (TPVs)) 

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D. P. DeW itt. Theory and Practice of Radiation Thermometry. New York John Wiley Sons, 1988. J. C. Richmond. Applications of Radiation Thermometry. ASTM Special Technical Publication. American Society for Testing and Materials, 1984. 

Applications of radiation grafting in the coating industry for improving adhesion and other properties has been an active field. For instance, grafting of styrene onto polyester fibers was found to improve the interfa-cial adhesion between grafted chopped polyester fibers and polystyrene used as a matrix [139]. 

Carotenoid radicals — Many of the important oxidations are free-radical reactions, so a consideration of the generation and properties of carotenoid radicals and of carbon-centered radicals derived from carotenoids by addition of other species is relevant. The carotenoid radicals are very short-lived species. Some information has been obtained about them by the application of radiation techniques, particularly pulse radiolysis. Carotenoid radicals can be generated in different ways. "... 

Chemical synthesis is one important aspect of the application of radiation-chemical reactions in industry. Various kinds of radiation-induced syntheses are available, some of which will be described here. There are also nonsynthetic applications including, but not limited to, food irradiation, waste treatment, and sterilization by irradiation. Some of these will be taken up in the next section. 

Radiation techniques, application to the study of organic radicals, 12, 223 Radical addition reactions, gas-phase, directive effects in, 16, 51 Radicals, cation in solution, formation, properties and reactions of, 13, 155 Radicals, organic application of radiation techniques, 12,223 Radicals, organic cation, in solution kinetics and mechanisms of reaction of, 20, 55 Radicals, organic free, identification by electron spin resonance, 1,284 Radicals, short-lived organic, electron spin resonance studies of, 5, 53 Rates and mechanisms of solvolytic reactions, medium effects on, 14, 1 Reaction kinetics, polarography and, 5, 1... 

Development of new applications of radiation modifications of the properties of polymers in high technology industries such as electronics and the exposure of polymer materials to radiation environments as diverse as medical sterilization and the Van Allen belts of space have resulted in a renewed interest in fundamental radiation chemistry of polymers. 

Basic and applied researches on charged particle and photon-induced reactions of polymers are surveyed. The basic parts are fundamentals of radiation effects on polymers and pulse radiolysis studies on polymers. The intermediate parts are a great diversity of radiation effects on polymers and reaction mechanisms of electron beam (EB) and x-ray resists. The applied parts are economic scale of utilization of radiation and industrial application of radiation to polymers. 

The economic scale of the application of radiation in the field of agriculture in Japan was estimated from public documents to be about 964 million in 1997. The economic scale survey in food irradiation and mutation breeding was extended to the United States for a direct comparison to the situation in Japan. The maximum estimation amounted to 3.2 billion for food irradiation and 11.2 billion for mutation breeding. The economic scale for products in selected agricultural fields was 14.5 billion for the United States and about 0.8 billion for Japan, implying that the former is larger in magnitude by a factor of about 18 [5]. 

INDUSTRIAL APPLICATION OF RADIATION TO POLYMERS 4.1. Electron Beam and X-Ray Resists... 

Application of Radiation Chemical Reactions to the Molecular Design of Functional Organic Materials... 

Two independent and one dependent factor govern the applicability of radiation to any process. It is necessary to know the cost/roentgen and the quantity of product/roentgen. Knowledge of these allows one to calculate the cost/pound of the radiation processing. It must then be ascertained whether the value added to the product is greater than the cost of the treatment. Each of the independent factors will be treated in following sections. 

The fact that the pharmaceutical industry indulges in the separate sterilization of products and containers has previously been mentioned (Sec. IVGlc). Three general applications of radiation sterilization therefore exist radiation of (1) the product, (2) the containers, or (3) the product in the container. The first possibility has been discussed the others deserve elaboration. 

Areas of application of radiation degradation of polymers can be usefully classified into (1) modification of polymers, e.g. molar mass or structure, (2) radiation-sensitive polymers, and (3) radiation-resistant polymers. Within the constraints of the required material properties of the polymers, either maximization or minimization of the response to radiation is usually the objective. 

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