Compound physical properties

Cobalt difluoride [10026-17-2] C0F2, is a pink solid having a magnetic moment of 4, 266 x 10 J/T (4.6 Bohr magneton) (1) and closely resembling the ferrous (Fep2) compounds. Physical properties are Hsted in Table 1. Cobalt(II) fluoride is highly stable. No decomposition or hydrolysis has been observed in samples stored in plastic containers for over three years. 

Properties. Sulfolane [126-33-0] C4HgS02 (1), also known as tetrahydrothiophene-1,1-dioxide and tetramethylene sulfone, is a colorless, highly polar, water-soluble compound. Physical properties are given ia Table 1 (1). 

Oils of the three types are offered in a range of viscosities and this will influence their processing character to some extent, although there is little evidence that it will have much influence on the ultimate compound physical properties, at least in natural rubber compounds. The small additions of oil to a compound help with filler dispersion by lubricating the polymer molecular chains and thus increasing their mobility. There will also be some wetting out of the filler particles which enables them to achieve earlier compatibility with the rubber and improve their distribution and dispersion speed. 

A general account of how the CHETAH program may be applied to estimation of chemical hazards in relation to process research and development has been given [10], Progressively enhanced and user-friendly versions of CHETAH, which give an overall hazard assessment and are capable of running on personal computers are available from ASTM [11], Comments critical of the criteria used for hazard evaluation in the 1994 CHETAH program [12] led to amendments and enhancements incorporated in the 1998 Windows version. The pure compound physical properties databank has since been expanded from 400 to 1500 compounds and the... 

Lanthanum sulfate is used to prepare many lanthanum compounds. Physical Properties... 

Because of its relatively fine particles and high surface area, carbon black has a much more significant effect on compound physical properties than do other... 

Solid-state characterization is one of the most important functions of the preformulation group, which is assigned the responsibility of making recommendations for further formulation work on a lead compound. Physical properties have a direct bearing on both physical and chemical stabilities of the lead compound. Much of the later work on formulation will depend on how well the solid state is characterized from the decisions to compress the drug into tablets to the selection of appropriate salt forms. The studies reported in this section, of course, apply to those drugs that are available in solid form, crystalline or amorphous, pure or amalgamated. 

Compounds, it is now in electronic form as Properties of Organic Compounds. The database includes about 30,000 compounds physical properties and spectral data (mass, infrared, Raman, ultraviolet, and NMR) are covered. It is offered as CDROM [www.crcpress.com] and by Web access [www.chemnetbase.com]. 

PHYSICAL PROPERTIES Appearance and odor vary depending upon the specify organic arsenic compound. Physical properties of specific compounds are provided for illustrative purposes, (arsenic diethyl) liquid or oil BP (185-190 C, 365-374°F) DN (about 1.0 g/mL) SG (about 1.0). (arsenic dimethyl) colorless to yellow oily liquid MP (-6°C, 21.2°F) BP (186°C, 366.8°F) DN (1.15 g/mL) SG (1.15). (arsenoacetic acid) minute yellow needles does not melt below 260 C (500°F) decomposition begins at about 205°C (401 F) readily soluble in pyridine, dilute sodium carbon-ate and dilute sodium hydroxide solutions insoluble in water and common organic solvents. 

Figure 9.5 illustrates the general trends for tread-grade carbon black loading and the effect on compound physical properties. As carbon black level increases, there are increases in compound heat buildup and hardness and, in tires, an increase in rolling resistance and wet skid properties. Tensile strength, compound processability, and abrasion resistance, however, go through an optimum after which these properties deteriorate. 

Surface hydration caused by water vapor absorption is affected by surface silanol concentration. High levels of hydration can adversely affect final compound physical properties. Silicas are hydroscopic and thus require dry storage conditions. 

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