What are the common quality problems of PVC foam board and how to solve them?

PVC foam board, as a lightweight and high-strength building material, has been widely used in construction, advertising, decoration and other fields. However, in the process of production and use, PVC foam board often encounters some quality problems, which not only affect the appearance and performance of the product, but also may cause hidden dangers to the safety of use.

1. Common quality problems
Yellowing of the board surface
PVC materials will be affected by various factors such as light, heat, and oxygen during long-term use, resulting in chemical reactions such as molecular chain breakage and cross-linking of the material, which will cause material aging. The surface of the aged PVC material will turn yellow. In the production process of PVC foam board, if the extrusion temperature is too high, the stabilizer in the PVC material will decompose, which will cause an oxidation reaction. This oxidation reaction will turn the surface color of the board yellow. PVC foam board is exposed to ultraviolet rays for a long time in the outdoor environment. Ultraviolet rays will accelerate the aging process of PVC materials and cause the surface of the board to turn yellow. The use environment of PVC foam board will also affect its board color. For example, in a humid, high-temperature, and highly polluted environment, the board is more likely to age and discolor.

Board bending
During the production process, due to improper extrusion process control or unreasonable mold design, PVC foam board may have board bending problems. This not only affects the appearance of the product, but also may affect the use effect.

Uneven board thickness
During the production process, PVC foam board is prone to uneven board thickness due to uneven material flow or improper mold temperature control. This may cause uneven force and deformation of the board during use.

Poor cell structure
The cell structure is one of the important properties of PVC foam board, which directly affects the strength and thermal insulation performance of the board. If the cell structure is poor, such as the cells are too large, too small or unevenly distributed, it will affect the performance of the board.

2. Solution
For the problem of yellowing of the board surface
In order to solve the problem of yellowing of the PVC foam board surface, the following measures can be taken:

Optimize the production process, reduce the extrusion temperature, and reduce the oxidation reaction of the material at high temperature.

Select PVC resins and stabilizers with better stability to improve the heat resistance and oxidation resistance of the material.

Strengthen quality control during the production process to ensure that each process meets the process requirements.
For the problem of bending of the board surface
In order to solve the problem of bending of the board surface of PVC foam board, the following measures can be taken:

Adjust the mold design to ensure the accuracy and stability of the mold.
Optimize the extrusion process, control the material flow speed and temperature distribution, and ensure that the board is evenly stressed during the extrusion process.
Add a straightening device during the production process to straighten the board and improve the straightness of the board.
For the problem of uneven board thickness
In order to solve the problem of uneven board thickness of PVC foam board, the following measures can be taken:

Adjust the die lip opening to ensure uniform material flow.
Add a flow blocker to adjust the material flow speed and direction to make the board uniform in thickness during extrusion.
Strengthen mold temperature control to ensure stable mold temperature and avoid uneven board thickness due to temperature fluctuations.
For the problem of poor pore structure
In order to solve the problem of poor pore structure of PVC foam board, the following measures can be taken:

Optimize the selection and dosage of foaming agent to ensure that the foaming agent is evenly dispersed in the PVC resin.
Control the extrusion speed and temperature to ensure that the material is fully foamed during the extrusion process.
Add pore structure detection equipment during the production process to monitor and adjust the pore structure of the board in real time.