Product Yellowing/Discoloration

Transparent or light-colored products show an unwanted yellow tint. Discolored areas are mostly concentrated in the thick-walled core of the product or high-temperature areas, accompanied by a simultaneous decline in mechanical properties.

(1) In terms of temperature parameters: the curing exotherm temperature is too high, causing thermal oxidative decomposition, it may cause thermal degradation of the material or loss of control of the reaction rate, destroying the internal structure of the product. (2) Process factors: ultraviolet light exposure triggering photo-aging, this factor affects the product's '2079851475616104453 and final quality. (3) Process factors: oxidation and discoloration of amine curing agents, this factor affects the product's '2079851475616104453 and final quality. (4) Process factors: discoloring impurities contained in the formula, this factor affects the product's '2079851475616104453 and final quality.

(1) Process control: control the maximum curing exotherm temperature, establish an online monitoring mechanism, set upper and lower parameter limits, and implement alarm management. (2) Formula optimization: add ultraviolet absorbers and antioxidants, determine the optimal addition amount through small-batch tests and verify its impact on the comprehensive performance of the product. (3) Material selection: select curing agents that are not easily discolored, such as alicyclic amines, establish material selection evaluation standards and determine the optimal plan through comparative tests. (4) Material selection: use high-purity raw materials., establish material selection evaluation standards and determine the optimal plan through comparative tests. (5) Preventive measures: establish a complete process control standard and quality inspection system, and regularly review process data for continuous optimization.

This problem requires comprehensive analysis from multiple dimensions of materials, processes, equipment, and operation, and should be solved by systematically optimizing process parameters and the quality control system.