Inherent specific gravity

Inherent specific gravity of a PTFE part free of voids can be calculated from Eq. (10.6) as a function of crystalline content. 

After substituting from Eq. (10.7) into (10.6), the relationship between crystallinity and inherent specific gravity is reached. 

Figure 10.40 graphically illustrates the relationship between inherent specific gravity and crystallinity of a part. Equations (10.5) and (10.8) can be used to calculate specific gravity of a part at different void contents, as shown in Fig. 10.40. 

Composites can be created ia which the core optimizes desired physical properties such as modulus, whereas the outer layer optimizes surface coasideratioas aot inherent ia the core material. SoHd outer—foam core can provide composites with significant reductions ia specific gravity (0.7). Dry blowiag ageats can be "dusted" onto the peUets orHquid agents iajected iato the first transitioa sectioa of the extmder. 

Horton and Aubrey (34) handpicked pure vitrain samples from coals and separated them into five different specific gravity fractions. They then analyzed these for 16 minor elements. They concluded that for the three vitrains they studied, beryllium, germanium, vanadium, titanium, and boron were contributed almost entirely by the inherent (organically combined) mineral matter and that manganese, phosphorus, and tin were associated with the adventitious (inorganically combined) mineral matter. 

When the chemist first receives a toxicant for formulation, a determination of the following physical properties will be of material aid to his studies (a) melting point or boiling point, (b) rate of hydrolysis, (c) vapor pressure, (d) specific gravity, (e) solubility, (f) ultraviolet degradation, and (g) inherent biological activity. 

There is no need for a stirrer as the reacting liquids are mixed by the natural flow resulting from the difference in specific gravities of the components. Because of certain drawbacks inherent in the difficulty of removing the heat of reaction, and as an emulsion may be formed, the method has not found any permanent practical uses. 

SPS is entirely different from conventional amorphous styrenics in chemical and physical properties. In addition to characteristics such as low specific gravity, excellent electrical properties, hydrolytic resistance and good mold-ability similar to those of existing styrenics, SPS has heat resistance, chemical resistance and the characteristics inherent to crystalline polymers that make it a new engineering plastic. SPS is finding new applications and is expected to bring out new horizons in the application areas of engineering thermoplastics. 

Bulk property detectors, and in particular, the refractive index detector, have an inherently limited sensitivity irrespective of the instmmental technique that is used. Consider a hypothetical bulk property detector that monitors, for example, the density of the eluent leaving the column. Assume it is required to detect the concentration of a dense material, such as carbon tetrachloride (specific gravity 1.595), at a level of 1 pg/ml in w-heptane (specific gravity 0.684). 

The test method covers the determination of the bulk density and specific gravity of materials in their as manufactured form. Therefore, this test method evaluates a product, not an inherent material property. ... 

Material Strength or Mechanical Properties. The U.S. FPL Wood Handbook (1) provides a starting point to determine the generic range of properties. Actual properties inherent to the artifact s fabric should be analyzed whenever possible, however, to establish a more accurate data base. In particular, determination of density, or specific gravity (essentially a factor of the Sg layer thickness), is important it relates directly to the homogeneous material s mechanical and physical properties. 

Mineral matter content ranges from 3% to 60% (mineral ash) at different mines. Most of the ash is introduced for the roof or bottom of the mine or from partings (small seams of slate) in the coal seam. This mineral matter (extraneous ash) is heavier than 1.80 specific gravity the remaining mineral matter is inherent in the coal. The density of coal increases with the amount of mineral matter ash present. 

Even though vulcanized EPDM has some oil resistance, in contrast to unvulcanized EPDM which has virtually none, a rubber with inherent oil resistance should be even better. For this reason, more polar rubbers have replaced EPDM in applications where oil resistance is critical. Dynamic vulcanizates of nitrile rubber with polypropylene are the most important example. Commercial grades are somewhat harder than EPDM equivalents (between 70 on the Shore A scale to 40 on the Shore D scale) and are also more dense (about 1.0-1.1 specific gravity) (26,49). 

Cannon-Fenske viscometer n. Capillary viscometer (calibrated) used for measuring relative flow time for liquids, useful for determining relative, specific and inherent viscosities of polymer solutions and extrapolation of intrinsic viscosities. It is convenient to clean and calibrate, but lacks correction due to different volume levels leading to weight due to gravity in the viscometer See image). 

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