【Science popularization dry goods】Do you surely know anything about PVC film?

Soft PVC films are of great significance in various sectors of the national economy and in the defense and military industry. Various specifications of soft PVC films and their main uses are shown in the table below.

The types of PVC film produced in China include:
Industrial film (0.23mm), agricultural film (0.10mm), packaging film (0.10, 0.14, 0.20mm), book cover film (0.35mm), as well as grain packaging film, civilian film, insulation film, etc.
For the quality requirements of soft PVC film: Taking agricultural film as an example, its physical and mechanical properties are as follows:
Tensile strength (longitudinal and transverse) ≥ 150 (kg/cm) each ²)
Breaking elongation base (longitudinal and transverse) ≥ 200 (%)
Low temperature elongation (longitudinal and transverse) ≥ 20 (%)
Right angle tear strength (longitudinal and transverse) ≥ 40 (kg/cm) ²)
Heating loss rate ≤ 8 (%)
Water extract ≤ 1.0 (%)
The appearance quality requirements of the film are: transparent, no bubbles, no garbage or impurities, uniform thickness, neat winding, low shrinkage, and no wrinkling or unevenness.