Thermoplastics color compounding

Several anthraquinone dyes are used in dyeing thermoplastics such as polymethacrylate, (modified) polystyrene, and polycarbonate. The dyes also are used in combination with titanium dioxide or other materials to provide body colors for the thermoplastics. Initially compounds with relatively simple structures were used, many of them drawn from stocks of existing intermediates. Since then new products designed to satisfy the specific requirements have become available. 

Uses Dispersant/processing aid in compounding of thermoplastic color cones, and min. orfre retardant-filled plastics Features Environmentally friendly... 

Color/Transparency. Almost all amorphous engineering thermoplastics, except PC and some polyester carbonates, are inherently colored. Even polycarbonates have yellowness indexes (YI) (36) of 0.1 to 5.0. Colorless material is produced from these resins by compounding with complementary blue dyes which reduce transmission. Ha2e in amorphous resins is an indication of particulates. Ha2e reduces optical clarity and transmission. 

Until fairly recently most plastics were purchased fully compounded in the colour required for moulding or extrusion, but with a view to offering ranges of colours more cheaply and conveniently it is quite usual now for machines to be fed with blends of natural thermoplastic and masterbatch—a convenient wax-like base containing appropriate concentrations of colorant and other additives (such as anti-static agent). The supply of masterbatches has become an important specialized business. 

Plastics Chemicals PVC Compounds Thermoplastic Products Colorants Additives Rubber Products Basic Chemicals... 

The attributes and properties of compounded plastics are applicable to many diverse applications. Although the focus of this chapter is the compounding of thermoplastic materials, many of the principles and comments also apply to thermoset polymers such as phenolics. The chapter will discuss compounding methods, the roles and challenges of additives, and techniques for introducing color to compounded plastics. 

Suspensions of polyacetylene were prepared as burrs or fibers (46) by using a vanadium catalyst. When the solvent was removed, films of polyacetylene were formed with densities greater than that prepared by the Shirakawa method. These suspensions were mixed with various fillers to yield composite materials. Coatings were prepared by similar techniques. Blends of polypyrrole, polyacetylene, and phthalocyanines with thermoplastics were prepared (47) by using the compounding techniques typically used to disperse colorants and stabilizers in conventional thermoplastics. Materials with useful antistatic properties were obtained with conductivities from 10" to 10" S/cm. The blends were transparent and had colors characteristic of the conducting polymer. For example, plaques containing frans-polyacetylene had the characteristic violet color exhibited by thin films of solid trans-polyacetylene. 

Used as a thermo/light-stabilizing phenolic antioxidant in the manufacture (compounding and end use) of white, light-colored, and transparent vulcanizates based on natural or synthetic rubber, PS, polyolefins, and pentaplast. Also used in POM and ABS thermoplastics because of its low volatility and migration properties. 

Thermal Dehvdrochlorination. PVC, per se, is unstable and, at moderate temperatures, undergoes decomposition with loss of HCl. The successful commercial development of PVC is largely due to the fairly complex technology involving development of stabilizers that neutralize the evolved HCl and result in improved color of the compounded polymer so that it can be processed like other thermoplastics. 

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