Chemical structures protectors

Industries testing protocols focus on the quantification of radiation-induced changes in the protected material but not on the additive used as a protector. Drug substances (actives) sometimes have chemical structures, which are very sensitive to electromagnetic radiation in the UV and/or visible (VIS) range. 

Phosphorus The main role of phosphorus in carbon materials is as an oxidation protector and a fire retardant [136-144]. Its source can be in phosphoric acid, which is used in some technologies of carbon activation [143,144] or in the cross-linking precursor. The phosphorus present in the carbon matrix is stable between 773 and 1273 K. It can be fixed as red phosphorus and/or in chemically bonded forms, such as -C-P-bonds or -C-O-P-bonds [143-145]. During the carbonization process at low temperatures, phosphocarbonaceous species are created. Their content decreases by scission of the P-O-C bonds with an increase in the temperature, due to the growth of aromatic structures [143]. Possible phosphorus-containing functionalities are presented in Figure 2.4. 

Electrochemical protection is divided into cathodic and anodic protection. Cathodic protection based on the change of potential of a metal in the negative direction is realized in electrolytic environments, in most cases neutral, mainly of steel and reinforced concrete structures. A well-designed and correctly realized CP reduces the corrosion rate to almost zero. In practice it is realized with the use of an impressed current or protectors (galvanic anodes). The scope of application is enormous and continuously increases. With the use of this technology it is possible to protect vessels and ships, docks, berths, pipelines, deep wells, tanks, chemical apparatus, underground and underwater municipal and industrial infrastructure, reinforced concrete... 

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