Structural Inhibited Plastics

In contrast to film materials, express estimates of the protective ability of inhibited structural plastics have been insufficiently elaborated so far. For example, the effect of inhibited plastics on the wear rate of metal samples has been studied by the authors of [100] using a pendulum tribometer containing a plastic-metal friction pair. Corrosion tests of systems such as inhibited structural plastic-metal counterparts are usually conducted in real operation regimes [44]. 

Parts of friction joints and seals are often made from inhibited structural plastics (see Chap. 4). Their main role in metal-polymer friction joints is to abate Mechano-chemical wearing of metal counterbodies. Application of inhibited antifrictional materials is considered to be a promising trend for extending the life of friction joints operating in hostile media. The structural polymers or their blends most often contain plasticizers. Cl, fillers and modifiers as additional components. The inhibited plastics are employed in plain bearings, sealing elements and other members of oil-extracting equipment and vehicles. 

Inhibited structural plastics are manufactured by the extrusion of blends of structural polymers and Cl. 

Mechanisms of Degradation Inhibitors. The degradation mechanisms described above have no little effect on end-use stability and processing stability of polypropylene. Indeed, without stabilizers and antioxidants to inhibit such degradation reactions, polypropylene would have limited usefulness as a structural plastic if any usefulness at all. 

Furthermore, an idea of obtaining inhibited plastics by filling polymer binders with solid inhibitor particles has apparently been realized. A wide range of structural plastics, films and coatings containing powder inhibitors is produced by the major companies of the world at the present time. The... 

Inhibited foam plastic is a structural material preliminary foamed by Cl vapors or based on foamed inhibited plastics and is used for plastic-based containers. The inhibited vapor phase can be introduced into the polymer base by one of the following methods. 

Inhibited foam plastics are predominantly of a closed-cell structure, which means that the vapor phase is insulated in each cell from the neighboring cells by polymer walls. Diffusion of Cl through the cell walls inside polymer containers made of this inhibited foam plastic diminishes the possibility of corrosive damage of the packed hardware. 

Friction parts made from structural inhibited plastics retard mechanochem-ical wear of conjugated metal counter bodies. Liberation of volatile Cl from plastic units located in a closed volume hampers corrosion of all metal elements of the design found in this volume. The cost effectiveness of structural plastics is mainly composed of the reduction of repair expenses of the equipment. 

One example is the use of rigid selfexpanding closed cell polyurethane foams as a method to inhibit corrosion of the interior surfaces of metal (steel, etc.) structural cavities exposed to seawater and moisture is one of many example of plastic providing corrosion protection. Unfilled metal cavities are a general feature of various structures or products used in the marine, building, electronics,... 

Folpet is a protective leaf fungicide. Its mode of action inhibits normal cell division of a broad spectrum of microorganisms. It is used to control cherry leaf spot, rose mildew, rose black spot, and apple scab. It is used on berries, flowers, ornamentals, fruits and vegetables, and for seed- and plant-bed treatment. Folpet also finds use in paints, plastics, and treatment of internal and external structural surfaces of buildings to control fungal attack.50,52... 

Because of its cylindrical shape and hydrophobic character, cholesterol is an important component of the membranes of animal cells. Its rigid structure decreases membrane fluidity, but it also inhibits the crystallization of fatty acid side chains of the membrane lipids and it acts as a sort of membrane plasticizer. 

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