The Five Factors Causing Color Change And Color Deviation in Flame-retardant Modified Materials

The Five Factors Causing Color Change And Color Deviation in Flame-retardant Modified Materials

1. The inherent instability of the raw materials

Some resins on the market do not have antioxidants or stabilizers added during the processing, and the plastic products begin to discolor immediately after being extruded from the extruder. There are also instances where plastic products discolor during storage, but when other manufacturers' or grades of resins are used, no discoloration occurs. This indicates that the quality of resins on the market varies, and it is necessary to seek out and use raw materials with good stability.

2. The flame retardant has poor heat resistance.

When the temperature is below the processing temperature of the material, the flame retardant decomposes to form small molecule substances, which leads to a change in the color of the entire system. For example, the processing temperature for polypropylene (PP) is 170-230°C, for polyamide 6 (PA6) it is typically 230-290°C, and for polyamide 66 (PA66) it is 240-310°C. The flame retardants used for PP, PA6, and PA66 may therefore differ.

3. The filler contains an excess of metal impurities

Excessive impurities such as iron, nickel, and chromium, under certain conditions of incomplete oxidation, form corresponding oxides, causing the plastic products to change color. For example, iron oxidizes in the air to form red iron oxide, which causes the color of plastic products to become darker. Common fillers include titanium dioxide (titanium white) and calcium carbonate.

4. Factors related to other additives

Common processing and modification aids include antioxidants, plasticizers, reinforcing agents, coupling agents, lubricants, colorants, crosslinking agents, flame retardants, antistatic agents, antibacterial agents, impact modifiers, and degradants, among others.

During the processing (especially under high-temperature conditions), it is required that these additives do not undergo chemical reactions with each other and maintain their own stability to prevent oxidation and decomposition.

5. Environmental Factors

Various substances present in the air can adsorb or chemically react with modified materials. For instance, some NOx are inherently colored substances; nitrogen dioxide (NO2) is a brown-red, highly reactive gas. When a large amount of NOx adheres to or is absorbed onto the exposed edges of plastic products, it inevitably causes the edges of the plastic products to discolor.

External factors such as light and heat can also cause certain components in plastics to undergo chemical reactions, leading to degradation and discoloration.

The above five points are common main causes that may lead to color changes in plastics during production and storage processes. Of course, specific situations require specific analysis. Only by considering all influencing factors can we ensure that the product's color quality meets market and customer demands, ultimately leading to a win-win situation.

6. Conclusion

The flame retardants developed by Yinsu Flame Retardant Company exhibit excellent performance in maintaining the original color of materials, minimizing the color change issues that can arise from the addition of flame retardants, ensuring the color stability and consistency of the products. Moreover, to meet the special needs of black products, Yinsu Flame Retardant Company has also developed blackened red phosphorus masterbatch.

This masterbatch has been pre-adjusted for color, eliminating the need for customers to go through the tedious process of color adjustment. It can be directly added to black products, greatly simplifying the production process, improving production efficiency, and also saving on production costs. These innovative research and development achievements of Yinsu Flame Retardant Company provide customers with more flexible and efficient solutions for flame retardant treatment of products in various colors, meeting the diverse needs of the market.