Flex resistance

PTFE is used for lining chutes and coating other metal objects where low coefficients of friction or non-adhesive characteristics are required. Because of its excellent flexing resistance, inner linings made from dispersion polymer are used in flexible steam hose. A variety of mouldings are used in aircraft and missiles and also in other applications where use at elevated temperatures is required. 

This material finds a limited application in films and coatings which require good abrasion and flexing resistance. Some typical properties of cross-linked and uncross-linked polymers are given in Table 18.9. 

ECTFE resms have high tensile strength, moderate soffness, high flex resistance and impact strength, and excellent cut-through resistance They exhibit good... 

Greater resistance toward solvents and greater flex resistance. 

The key performance properties of conveyor belts, particularly belt cover compounds, are flex resistance, abrasion resistance, and low heat buildup. The effect of l,3-bis(citraconimidomethyl) benzene on these key properties, in addition to cure characteristics and tensile properties, has been evaluated in a typical, NR-based belt cover formulation listed in Table 14.49. 

The coiling together of textile staple fibres, yams or threads to give the structure the required degree of strength, extensibility, flex resistance, etc. Twist is designated as so many turns per inch and either right hand (Z) or left hand (S). See S-Twist and Z-Twist. 

Fig. 14. Mastication of polystyrene — synthetic rubbers systems. Effect of the amount and type of rubber on dynamic flex resistance. 1 styrene rubber (SKS 30) 2 nitrile rubber (SKN 18) ...

Additive Amount, g/lOOg resin Flex resistance kg cm/cm2 Dynamic Static ... 

Butyl rubber is produced by a process in which isobutylene is copolymerized with a small amount of isoprene using aluminum chloride catalyst at temperatures around — 150° F. (20). The isoprene is used to provide some unsaturation, yielding a product that can be vulcanized (43). Vulcanized Butyl rubber is characterized by high tensile strength and excellent flex resistance furthermore, as a result of its low residual unsaturation (only 1 to 2% of that of natural rubber) it has outstanding resistance to oxidative aging and low air permeability. These properties combine to make it an ideal material for automobile inner tubes (3), and Butyl rubber has continued to be preferred over natural rubber for this application, even when the latter has been available in adequate supply. 

Neoprene is the generic name for polychloroprene rubber. It has been produced commercially since 1931 and had rapid and wide acceptance because it is much superior to natural rubber for heat and oil resistance. Heat resistance is far better than NR, BR or SBR. but less than EPDM. When heated in the absence of air, neoprene withstands degradation better than other elastomers which are normally considered more heat resistant, and retains its properties fifteen times longer than in the presence of air. Compression set at higher temperature is better than natural rubber and 100°C is typically the test temperature rather than 70°C. Abrasion resistance is not as good as natural rubber but generally better than most heat resistant and oil resistant rubbers. This is also true for tear strength and flex resistance. 

Provides antiozonant and antioxidant properties with high temperature, fatigue and flex resistance to rubber compounds. Used in pneumatic tire components, solid tires, belts, hoses, cables, automotive mounts, bushings and general mechanical products that are exposed to continuous and intermittent dynamic operating conditions that require protection from ozonation. 

Use Flex-resistant antioxidant in rubbers stabilizer polymerization inhibitor retards copper degradation intermediate for dyes, drugs, plastics, and detergents. 

PE/CSR 20°C Nr e-, 50-200 TGM-3 Tensile strength, elongation at break, equilibrium modulus, rigidity, density, gel fraction, degree of swelling, flexing resistance, aging 41... 

Pinhole flex resistance is the ability of a plastic film to resist the formation of pinholes (tiny holes) during repeated folding. Films having a low value of pinhole flex resistance will tend to generate pinholes at the fold line during repeated flexing. The test is described in ASTM Standard F456. Pinhole flex resistance is related to... 

B. Promoting the Removal of Pills by Lowering the Flexing Resistance of the Synthetic Fiber ... 

Udng these methods, the melt viscodty undergoes dgnificant changes, when molecular weight and tenqierature are held constant. TIk same is also true for tte mechanical properties of the fiber especially the flexing resistance. The various pro-... 

ExxonMobil OPPalyte films are coated, pearlescent white, opaque OPP films, with a proprietary core providing excellent opacity, good machinability, excellent flavor and aroma barrier properties, good oxygen barrier properties, excellent stiffness and flex resistance, excellent print performance, strong cold seal adhesion, and good bond strength. 

Pinhole Flex Pinhole flex is the testing by which flex resistance of a specimen ean be determined. Pinhole formation is the criterion presented for measuring failure. 

Ethylenebis (oxyethylene) bis (3-t-butyl-4-hydroxy-5-methylhydrocinnamate) antioxidant, lubricants incidental food-contact p,p -Dioctyldiphenylamine Hexamethylenebis (3,5-di-t-butyl-4-hydroxycinnamate) Pentaerythrityl tetrakis [3-(3, 5 -di-t-butyl-4-hydroxyphenyl) propionate] Thiodiethylene bis (3,5-di-t-butyl-4-hydroxy) hydrocinnamate antioxidant/antiozonant, epichlorohydrin Nickel diisobutyidithiocarbamate antioxidant/antiozonant, flex-resistant polyolefin... 

N,N -Diphenyl-p-phenylenediamine antioxidant/antiozonant, flex-resistant rubber N,N -Diphenyl-p-phenylenediamine antioxidant/antiozonant, footwear... 

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