Reasons for brittleness of the whole product in the production of injection moulds1.注塑机射出和保压压力不足；
1. Insufficient injection and holding pressure of injection moulding machine;2.背压太小、原料不够扎实；
2. The back pressure is too small and the raw materials are not solid enough.
3. When the back pressure is too high, the heat of shearing and friction increases.
4. Shooting speed is too slow to crystallize sufficiently.
5. Mould temperature is too high, raw materials are overheated, decomposed and deteriorated.
6. Mould temperature is too low to crystallize sufficiently.
7. Shortage of injection and holding time;8.注塑机停机时间太长了和注塑周期太长；
8. The downtime of injection moulding machine is too long and the injection moulding cycle is too long.
9. Storage time is too long.
10. The proportion of secondary recycling in new materials is too large.
11. The strength and toughness of raw materials are not enough and the viscosity is not enough.
12. unreasonable additives or too much additives;13.原料未充分烘干；
13. Inadequate drying of raw materials;
14. The internal structure of the product is too thick in some places, too thin and uneven in some places, and the feeding place is unreasonable.
15. Inhomogeneous feeding of mould and insufficient cooling well;16.产品壁厚太。
16. The product wall thickness is too thin.
17. The temperature of injection moulding machine is high, low and unstable.
18. The material pipes of the injection moulding machine are not cleaned up properly.
19. If the ejection is unreasonable, the stress of the plastic body increases and the fracture occurs.
20. The cooling circuit of plastic parts die is not arranged properly.