Hardness greases

Mechanical Properties. Greases vary in consistency from soap-thickened oils that are fluid at room temperature to hard brick-type greases that are cut with a knife. 

The soft-film solvent-deposited type can be used broadly for the same purposes as the hard-film type. A grease-resistant wrapping is required as an inner wrapping (as for all soft-film types) in packaging. Grades of this... 

The practice of corrosion inhibition requires that the inhibitive species should have easy access to the metal surface. Surfaces should therefore be clean and not contaminated by oil, grease, corrosion products, water hardness scales, etc. Furthermore, care should be taken to avoid the presence of deposited solid particles, e.g. stones, swarf, building materials, etc. This ideal state of affairs is often difficult to achieve but there are many cases where less than adequate consideration has been given to the preparation of systems to receive inhibitive treatment. Acid treatments, notably with 3-5% citric acid, with or without associated detergent washes, are often recommended and adopted for cleaning systems prior to inhibition. However, it is not always appreciated that these treatments will not remove particulate material particularly when, as is often the case, the material is insoluble in acids. 

Oils, greases, to hard thermoset composition, depending on M.W. and proportion of trifunctional unit2i... 

Figure 6. Scanning electron micrographs of hard-baked PMMA films before and after a 1.0-min oxygen-RIE treatment at the following conditions a, unetched and b, etched, 0.125 W/cm, 35 mTorr, -230 VDC, no thermal grease. Continued on next page.

Use a grease pencil to label three large test tubes D (for distilled water), H (for hard water), and... 

PP/NBR-V is appreciated for its resistance to hydrocarbons, oils and greases combined with a fair compression set, a broad hardness range, low density, good property/price ratio. 

A major use is as hthium stearate for lubricating greases. It makes a sohd grease that can withstand hard use and high temperatures. 

Uses of the alkali hydroxides.—A soln. of potassium hydroxide is used in the laboratory as an absorbent for carbon dioxide, the sodium compound is not so often used because of the formation of less soluble sodium carbonate which is liable to choke the delivery tubes with crystals. Potassium hydroxide is used in making soft soaps the corresponding sodium compound gives the ordinary hard soaps. The hydroxide fused with a little lime is used as a cautery—pierre a cautere. The alkali lye is also used as a cleansing fluid, since it forms soluble soaps with many greases and fats. The lye also dissolves animal tissues. 

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