How to optimize the performance of polyolefin shrink wrap film by precisely controlling the temperature of the hot furnace?

In the production process of pof shrink wrap film, the temperature of the hot furnace is the key link to control the stretching temperature. The stretching temperature, that is, the temperature of the molten polyolefin material during the stretching process, has a crucial impact on the final performance of the film. In order to ensure the smooth progress of the stretching process and optimize the performance of the film, the temperature of the hot furnace needs to be accurately set so that the tube (i.e. the molten polyolefin material) is in a temperature range above the softening point but below the melting point.

Above the softening point ensures that the material has sufficient fluidity to respond to the stretching force. During the stretching process, the molten polyolefin material needs to have a certain fluidity so that it can deform under the action of the stretching force. If the temperature is too low, the material will be too rigid and difficult to respond to the stretching force, resulting in uneven stretching or stretching fracture. Therefore, the hot furnace temperature must be higher than the softening point of the material to ensure that the material has sufficient fluidity.

Below the melting point, the material is prevented from melting and flowing during the stretching process, thereby maintaining the directional arrangement of the molecular chains. When the molten polyolefin material is close to the melting point, the activity of the molecular chain is significantly enhanced, and irregular melt flow is prone to occur. This flow will destroy the directional arrangement structure of the molecular chains formed during the stretching process, resulting in a decrease in film performance. Therefore, the temperature of the hot furnace must be lower than the melting point of the material to avoid the occurrence of melt flow.

Although the importance of hot furnace temperature setting is self-evident, it faces many challenges in actual operation. First, different types of polyolefin materials have different softening points and melting points, so the setting of the hot furnace temperature needs to be adjusted according to the specific material. Secondly, the precise control of the hot furnace temperature requires high-precision temperature control equipment and strict operating specifications to ensure that the range of temperature fluctuations is within an acceptable range. Finally, the setting of the hot furnace temperature also needs to consider the influence of process parameters such as stretching speed and stretching ratio to achieve the best stretching effect.

In order to meet these challenges, the following strategies can be adopted:
Material selection and testing: Before production, the selected polyolefin materials should be subjected to detailed performance tests, including key indicators such as softening point, melting point, and fluidity. According to the test results, determine the appropriate hot furnace temperature range.
Temperature control equipment upgrade: Use high-precision temperature control equipment, such as PID controllers, thermocouples, etc., to achieve precise control of the hot furnace temperature. Regularly calibrate and maintain the temperature control equipment to ensure the accuracy and stability of temperature control.
Process parameter optimization: Determine the optimal process parameters such as stretching speed and stretching ratio through repeated tests and optimization. The optimization of these parameters should be combined with the setting of the hot furnace temperature to achieve the best stretching effect and film performance.
Operation specification formulation: Formulate strict operation specifications, including the setting steps of the hot furnace temperature, the monitoring method of temperature fluctuations, and the handling process of abnormal situations. Through standardized operation, ensure the precise control of the hot furnace temperature and the smooth progress of the stretching process.

The precise setting of the hot furnace temperature has a significant impact on the performance of the pof shrink wrap film. The appropriate hot furnace temperature can ensure the smooth progress of the stretching process and avoid problems such as stretching fracture or uneven stretching. By accurately controlling the hot furnace temperature, the directional arrangement structure of the molecular chain can be maintained, thereby improving the key performance indicators of the film such as shrinkage, tensile strength, tear strength and transparency. The appropriate hot furnace temperature can also improve the heat sealing performance and cold resistance of the film, so that it can maintain stable performance in different environments.

Specifically, when the furnace temperature is set too high, the molten polyolefin material is prone to melt flow, destroying the directional arrangement structure of the molecular chain, resulting in a decrease in film performance. When the furnace temperature is set too low, the material will be too rigid and difficult to respond to the tensile force, which will also lead to poor film performance. Therefore, only at the appropriate furnace temperature can the best stretching effect and film performance be achieved.

In practical applications, there are countless successful cases of optimizing pof shrink wrap film performance by precisely controlling the furnace temperature. For example, in the field of food packaging, the use of optimized pof shrink wrap film can effectively extend the shelf life of food and maintain the freshness of food; in the field of electronic product packaging, the optimized pof shrink wrap film can provide better protection and buffering effects; in the field of pharmaceutical packaging, the optimized pof shrink wrap film can meet special requirements such as sterility, moisture resistance, and dust resistance.

With the continuous development of the packaging industry and the continuous improvement of consumers' requirements for packaging quality, the requirements for pof shrink wrap film performance will also become higher and higher. By optimizing the production process such as precise control of the furnace temperature, the performance level of pof shrink wrap film can be further improved to meet a wider range of application needs. As environmental awareness increases and the concept of sustainable development becomes more popular, the use of environmentally friendly materials and green production processes will also become an important trend in pof shrink wrap film production.