What may cause crazing in plastics?

Crazing in plastics is a phenomenon characterized by the formation of small cracks or fissures on the surface of the material. The primary cause of crazing is typically linked to large stresses that exceed the material's strength, combined with exposure to harmful solvents. When a plastic part is subjected to mechanical stress, it can lead to microscopic disruptions in the polymer chains.

Moreover, certain solvents can penetrate the plastic matrix, causing chemical interactions that weaken the material's structure. This weakening can make the plastic more susceptible to crazing under stress. Consequently, the presence of both stress and solvent exposure creates a conducive environment for the formation of crazes.

In comparison, inadequate heating during the manufacturing process can lead to defects but is not a primary cause of crazing. Similarly, exposure solely to extreme cold is unlikely to initiate crazing without the combination of stress or solvents. Finally, improper storage methods may lead to material degradation but do not directly correlate with the immediate mechanical and chemical factors that cause crazing.