Weather resistance carbon black pigments

The addition of pigments to polymers is a very effective practical method for increasing the resistance to photodegradation. Carbon black is by far the most effective. It has been used for years as a filler in rubber vulcanites, but in thermoplastic materials such as polyolefins it also has a protective effect against photodegradation. This was shown for the first time in 1950 by Wallder et al. [126] they demonstrated that the weathering properties of polyethylene are improved by the addition of about 2% carbon black. The effect is dependent on the degree of dispersion and on the size of the particles. Channel Black (particle size about 30 nm), for instance, is more efficient than Furnace Black (particle size 80 nm). The role of carbon black is not only to prevent the absorp-... 

Rubbers are used in a wide variety of service environments and share many of the requirements and features of other materials discussed in this book, although resistance to light aging is generally much less serious a problem than in plastics because of the extensive use of carbon black as a filler or pigment. Attention is therefore drawn to other chapters on environmental resistance and weathering. This section focuses on properties more closely identified with rubbers. 

The most common additives are colorants. Pigments, such as titanium dioxide and carbon black, and dyes, can be used to color PBT. At the same time, colorants can act as nucleating agents for speeding crystallization. Weather resistance of PBT, which is very important for outdoor applications, can be improved by coloring with carbon black. 

Carbon additives are used in polymer composites as fillers, reinforcing agents and pigments. In addition, carbon black is used to enhance UV stability, electrical conductivity and weather resistance. PP geotextiles containing carbon black are applied for soil reinforcement, filtration and other construction... 

Fluorinated surfactants reduce shrinkage of cement [29]. Cement tiles pigmented with carbon-black dispersions containing fluorinated surfactants are more weather resistant than tiles made with ligninsulfonate dispersants [30]. Fluorinated surfactants improve primers used for coating cement mortar [31]. 

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