Optimization strategies and influencing factors of the air tightness of Ultra Clear PET Film- Shanghai Hanker Industrial Co., Ltd.

Molecular structure is the basis of the air tightness of Ultra Clear PET Film. The arrangement and interaction of PET molecular chains determine the ease with which gas molecules pass through the film. By adjusting the polymer formula and synthesis process, the arrangement and interaction of PET molecules can be changed, thereby improving the gas barrier performance of the film. For example, the introduction of specific functional groups or cross-linking structures can increase the interaction between molecular chains and reduce the permeation channels of gas molecules.

Thickness is one of the key factors affecting the air tightness of Ultra Clear PET Film
. Generally speaking, the thicker the film, the stronger its gas barrier ability. This is because thicker films have more molecular chain layers, and gas molecules need to cross more obstacles to pass through. However, the increase in thickness will also bring about an increase in cost and an increase in processing difficulty. Therefore, it is necessary to reasonably control the thickness of the film while ensuring air tightness.

Crystallinity also has an important influence on the air tightness of Ultra Clear PET Film. PET films with high crystallinity have more orderly molecular chain arrangement, forming a tighter crystal structure, thereby improving gas barrier performance. By optimizing the crystallization conditions, such as increasing the crystallization temperature and extending the crystallization time, the crystallinity of the Ultra Clear PET Film can be improved, thereby enhancing its air tightness.

In addition to the above factors, post-processing is also an important means to improve the air tightness of the Ultra Clear PET Film. Through post-processing processes such as stretching, heat setting, and coating, the molecular structure of the film can be further improved, its density and strength can be improved, and its gas barrier ability can be enhanced. For example, the stretching process can make the PET molecular chain oriented along the stretching direction to form a tighter molecular structure; the heat setting process can make the film maintain a certain shape and dimensional stability at a certain temperature, further improving its air tightness.