Black grading

Carbon black grades identified by four characters (ASTM D1765-67), ie, cure rate of normal (N) or slow (S), digit classifyiag typical particle size ia am, and two arbitrarily assigned characters. 

The consumption of the vanous carbon black grades can be divided into tread grades for tire reinforcement and nontread grades for nontread tire use and other mbber appHcations. Table 9 shows the distnbution of production of types for these uses. In the United States 55% production is for tread grades. In Western Europe tread-grade production is 64%, and in Japan it is 60%. 

A method for measuring the diffuse reflectance from a black paste with a black tile standard. The low numbers represent the jettest or most intense black grades. 

Table 11 Hsts the types and appHcations of special pigment-grade carbon blacks. Included in this Hst are thermal black and lampblack. Over 40 special black grades have been developed based on the furnace process having a broad range of surface areas, from 20 m /g to over 1500 m /g. The lower surface area products are used in printing inks and tinting. The high area, more expensive products find use in high color enamels and lacquers.

PPE is moderately UV-sensitive but must be protected by addition of anti-UV and other protective agents. Generally, black grades are more resistant than natural ones. 

A brief description is given of two new black grades of Arpro expanded PP from Arco Chemical they are Arpro 5313 and 5319 and are destined for use in electronics and military materials handling applications. 

The trisazo dyes include in particular blue, green, and black grades. Diamines used are 4,4 -diaminobenzanilide (DABA) and 4,4 -diaminodiphenylaminc-2-sul-fonic acid (DADPS). The most important synthetic principle in this range is the type K i<— Di- K2<— D2. The sequence of the three couplings depends on the nature of the components. 

For a deeper understanding of structure-property relationships it is useful to consider the effect of carbon black grade and concentration as well as polymer type on the dielectric properties more closely. In Fig. 29 the real part of the a.c.-conductivity o at 20 °C of a series of rubber composites, consisting of the more polar statistical co-polymer NBR and the fine black N220, is depicted for various filler concentrations in the high frequency regime up to 1 GHz. For the lower carbon black concentrations, a power law behavior with exponent around 0.6 is observed, while the highly filled com-... 

The aim of this chapter is to provide an understanding of how carbon black particle size and shape translate into dispersion quality and other performance attributes in plastics applications. While this chapter focuses on carbon black s effectiveness as a pigment, some attention will also be paid to some of the other plastics performance properties it influences, such as stability against UV radiation, effects on mechanical properties, and electrical conductivity. At its conclusion, this chapter will help the reader select an appropriate carbon black grade for specific plastics applications. 

Three variables affect color performance of carbon black in plastics the particle size and shape or morphology of a carbon black grade, the polymer in which it is... 

Unlike diamond and graphite, which are crystalline carbons, carbon black is an amorphous carbon composed of fused particles called aggregates. Properties, such as surface area, structure, aggregate diameter and mass differentiate the various carbon black grades. 

Six types of carbon black are produced worldwide acetylene black, channel black, furnace black, gas black, lamp black and thermal black. Specific physical and chemical properties of a carbon black grade are summarized on its material safety data sheet and the suppliers product technical bulletin. 

FIGURE 31.2. SAXS-data for the carbon black grades N115, N121,andN339. 

Table 1 Natural rubber compounds with a range of carbon black grades ...

The carbon black critical loading factor and the optimum loading level tvill be a function of the specific carbon black grade and specific grade of polymers in the rubber compound blend, and are therefore unique for each polymer and filler system. 

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