The injection mold factory tells you what are the reasons for the brittleness of plastic products

The injection mold factory tells you what are the reasons for the brittleness of plastic products? Shanghai Mulan Injection Mold Factory has more than 10 years of industry experience. It is a precision plastic product factory that opens molds and assembles injection molding. What are the reasons and solutions for brittleness? Compared with the raw materials, the impact performance of plastic parts after injection molding has dropped significantly. This phenomenon is commonly known as brittleness. The direct cause of brittleness is that the inner parts of plastic parts .





1. Materials


1) There are impurities mixed in the raw materials or some other additives such as excessive solvents are added.


2) Under the influence of external atmospheric factors, raw materials undergo reactions such as catalytic cracking, which deforms plastic products.


3) The reuse rate of raw materials is too high or contains too much recycled material, and brittle cracks will appear after a long heating time in the barrel.


4) The plastic of the injection mold itself is of poor quality, for example, the molecular weight distribution is large, and the proportion of components containing uneven structures such as rigid molecular chains is too large; or it is polluted by other plastics, bad additives, dust and impurities, etc. brittle cause.





2. Injection mold design


Increase the size of the sprue, runner and gate. The runner should avoid sharp corners. Too small runner, runner or gate size and sharpness will lead to the decomposition of the polymer. Designing short and thick runners can reduce the pressure loss and temperature drop of the melt, and correspondingly reduce the injection pressure and cooling speed, thereby reducing the orientation stress and cooling pressure.


3. Injection molding machine


A suitable screw should be selected, and the temperature distribution will be more uniform during plasticization. If the temperature of the material is not uniform, it will easily accumulate too much heat locally, resulting in degradation of the material.





The injection mold factory tells you what are the reasons for the brittleness of plastic products? Shanghai Mulan Precision Products Co., Ltd. has served Japanese brands for 10 years, focusing on household beauty instruments, maternal and child feeding supplies, and finished product customization of small household appliances, providing appearance design , Sample production, circuit development, structural design, mold design, mold processing, injection molding processing, two-color mold, overmolding, two-color injection molding, overmolding, finished product assembly and other one-stop manufacturing solutions. The assembly department has 13 assembly production lines and 2 automatic assembly lines. The trust laboratory of the quality assurance department has 41 sets of experimental equipment, and the measurement room has 95 sets of measuring equipment. Welcome to inquire.