Polymers colorants

Styrene-Acrylonitrile (SAN) Copolymers. SAN resins are random, amorphous copolymers whose properties vary with molecular weight and copolymer composition. An increase in molecular weight or in acrylonitrile content generally enhances the physical properties of the copolymer but at some loss in ease of processing and with a slight increase in polymer color. 

The level of technical service support provided for a given product generally tracks in large part where the suppHer considers thek product to be located within the spectmm of commodity to specialty chemicals. Technical service support levels for pure chemicals usually provided in large quantities for specific synthetic or processing needs, eg, ammonia (qv), sulfuric acid (see SuLFURic ACID AND SULFURTRIOXIDe), formaldehyde (qv), oxygen (qv), and so forth, are considerably less than for more complex materials or blends of materials provided for multistep downstream processes. Examples of the latter are many polymers, colorants, flocculants, impact modifiers, associative thickeners, etc. For the former materials, providing specifications of purity and physical properties often comprises the full extent of technical service requked or expected by customers. These materials are termed undifferentiated chemicals (9),... 

Mechanical and Chemical Properties. Colorants, especially pigments, can affect the tensile, compressive, elongation, stress, and impact properties of a polymer (5). The colorants can act as an interstitial medium and cause microcracks to form in the polymer colorant matrix. This then leads to degradation of the physical properties of the system. Certain chemicals can attack colorants and there can be a loss of physical properties as well as a loss of the chromatic attributes of the colorant. Colorants should always be evaluated in the resin in which they will be used to check for loss of properties that ate needed for the particular appHcations. 

The thermal requirements for pigments which are targeted for PETP melt extrusion are particularly severe. However, it is important to consider the individual conditions at the various stages of polymer coloration. Pigments, for instance, which are added during the so-called condensation process in a glycol dispersion prior to transesterification or condensation in the autoclave, are exposed to temperatures between 240 and 290°C for 5 to 6 hours [43]. These harsh conditions are only tolerated by very few polycyclic pigments, primarily by representatives of the quinacridone, copper phthalocyanine, naphthalenetetracarboxylic acid, and pery-lene tetracarboxylic acid series. 

Note 3 Examples of additives are antioxidants, plasticizers, flame retardants, processing aids, other polymers, colorants, UV absorbers, and extenders [7]. 

The Ziegler-Natta catalysts are prepared by the reduction of TiIV compounds, e.g., TiCl4 or esters of titanic acid, by organoaluminum compounds. A higher catalyst activity and thus an improved polymer color is achieved by the use of MgCh as support component. 

The high normal stress differences in comparison to the shear stress cause flow phenomena which may influence many technical processes. One example is the Weissenberg Effect (see Fig. 3.10), which arises when a shaft rotates within a viscoelastic fluid. The first normal stress difference leads to a pressure distribution which causes the fluid to climb up the stirrer shaft. This effect occurs when processing polymer color dispersions or mixing cake dough. 

Heat stability Indicates maximum processing temperature at typical loading for typical processing times. These values assume no reactivity with any compound ingredients. The nominal heat stability also depends on the ability of the pigment to mask any shifts in polymer color that occur at the upper end of its processing temperature range. 

Many benzofuran-2-ones find application as dyes. For example, styryl analogues based on compound 262 were developed as a polymer colorant <2000W00053597>. Compounds 263 and 264 are among several stereoisomeric compounds that are patented as dyes <2000W00024736>. Dibenzofuran 265 is a photochromic compound for use as an ink or in plastic films <2001CNP1328109>. 

Reaction conditions Polymer color Residual styrene (ppm) A/n PD... 

Also of potential utility is the discovery that combinations of highly Lewis acidic metal salts, such as Al , with less acidic salts, such as Co , can produce mixed metal catalysts of high activity for PET polycondensation [34, 35]. This area of mixed metal polycondensation catalysis, which has been explored in only a limited way to date, may lead to optimized polymer color, stability, and maximum polymerization productivity during the coming generation. 

Ti, V, Cr, Mo Siloxane polymer 7t-Arene-complexed siloxane polymers (colored oils) 47... 

Polymer Color of Flame Odor of Vapor Other Notable Points... 

Calibration curves were generated for both polyamide and ABS to investigate the capability of the method in non-olefin polymers. Tables 8 and 9 demonstrate good agreement with theoretical values can be obtained in these polymer color concentrates. 

Whether you are working with neat polymers or blends of polymers, color and appearance must be engineered just like any other desired thermal or mechanical property. The ability to achieve the desired color can be adversely affected by the base polymer itself or the combination with other polymers, modifiers, additives or stabilizers. Even if the color can be achieved in the blended system, other performance attributes such as UV stability, flammability, or mechanical properties may be adversely affected as well. This paper looks at some of these color concerns in coloring polymers and blends. 

Uses Chelating agent with metal carboxylates as polymer additives esp. for chlorinated polymers color, heat, and light stabilizer for PC, poly-... 

ClearValue 3750 t[Clearvalue] Cofloc SP200 t[Specialized Polymers ] Color-Katch 54VH... 

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