Ester hydrolysis degradation appears in polylactic acid (PLA) foaming

PLA foamed products rapidly become brittle and lose strength after processing. This problem is relatively common in foam molding production and requires comprehensive analysis and solution from multiple aspects of material, process, and equipment.

(1) Material pretreatment aspect: PLA undergoes hydrolytic degradation in high-temperature water-containing environments, Moisture vaporizes at high temperature to produce gas or participates in side reactions, causing internal defects in the product. (2) Material pretreatment aspect: Chemical blowing agents (containing moisture) accelerate degradation, Moisture vaporizes at high temperature to produce gas or participates in side reactions, causing internal defects in the product. (3) Material aspect: Fluctuations in raw material performance indicators or insufficient pretreatment affect molding quality. (4) Process aspect: Control deviation of key process parameters causes the '2079851475616104453 to deviate from optimal conditions. (5) Equipment aspect: Equipment precision and maintenance status affect the stable execution of process parameters.

(1) Process control: Strictly control the moisture content of raw materials to ≤0.025%, Establish an online monitoring mechanism, set upper and lower parameter limits, and implement alarm management. (2) Material selection: Use physical blowing agents to replace water-containing chemical blowing agents, Establish material selection evaluation criteria, and determine the optimal solution through comparative tests. (3) Parameter adjustment: Reduce the processing temperature., Note that after lowering the temperature, it is still necessary to ensure the material fully reacts or melts; adjust step by step and observe the effect. (4) Preventive measure: Establish sound process control standards and a quality inspection system, and regularly review process data for continuous optimization.

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