Influence of pvc transparent film calendering effect
???????? The production process of PVC transparent film includes calendering and blow molding. Each process will have different effects on PVC transparent film and PVC film. The following will introduce the effect of calendering.
???????? We know that when the material passes through two rotating cylinders facing each other, due to the strong shear stress and tensile stress, the PVC molecules will undergo molecular orientation in the rolling direction, so that the film will have different physical and mechanical properties. Anisotropy, this is the rolling effect. The stronger the rolling effect, the greater the shrinkage of the product during secondary processing. This is due to the fact that the macromolecules in the original orientation are restored to only the curled state due to heat or stress relaxation.