transparent plastic products in medical application

As the plastic has a lightweight, good toughness, easy molding. Low cost, so in modern and daily products, more and more use of plastic instead of glass, especially for optical instruments and medical aspects, the development is particularly rapid. However, due to the requirements of its transparency is better, high wear resistance, impact toughness is better, so the composition of the plastic, the entire process of injection molding equipment. Mold, etc., have to make a lot of work to ensure that the plastic used to replace the glass, the surface quality is good, to achieve the requirements.

Transparent plastic must first have a high degree of transparency, followed by a certain degree of strength and wear resistance, to impact, heat resistance is better, chemical resistance is excellent, water absorption is small, only to use, to meet the transparency requirements and long-term deformation

This is the main properties of plastic products

Injection molding process characteristics of three kinds of commonly used transparent plastics

1, PMMA

The viscosity of PMMA is large, the fluidity is little, so it must be high temperature and high injection pressure. The injection pressure is helpful to improve the shrinkage of the product.

The injection temperature range is wide, the melting temperature is 160 DEG C, the decomposition temperature is up to 270 DEG C, so the material temperature adjustment range is wide, and the process is better. Therefore, improve liquidity, from the injection temperature.

2, PC

PC viscosity, melting temperature is high, poor liquidity must be at higher temperature injection (270~320 DEG C), relatively speaking, the temperature range is narrow, the process is not as good as PMMA.

Injection pressure has little effect on the fluidity, but because of the high viscosity, the injection pressure is still larger. To prevent internal stress, the holding time should be as short as possible.

High shrinkage rate, stable size, but the product of large internal stress, easy to crack, so should be used instead of increasing the temperature pressure to improve the liquidity, and by increasing the mold temperature, improve the mold structure and postprocessing to reduce the possible cracking.

3, PET

PET molding temperature is high, the material temperature adjustment range is narrow (260 - 300 DEG C), but after melting, the fluidity is good, therefore the craft is poor, and often in the nozzle to be added to prevent the flow device.

The mechanical strength and performance of the injection is not high, must be through the stretching process and modification to improve performance.

The accurate control of mold temperature is an important factor to prevent warpage.

At the same time transparent plastic products, easy to produce blooming