Unique among polymers are the PVC plastisols. Their uniqueness is limited only by the ability of the formulator. A skilled formulator can develop compounds that:
* Vary significantly in hardness
* Are available in clear or any color
* Release easily from a mold
* Adhere to many substrates
* Provide a tough non-porous material
* Have excellent aging characteristics
* Meet many diverse specifications
Neither mastication nor pressure containment, only heat, is necessary to convert these liquids to their final solid state. The progression of the physical state of a plastisol from a liquid to a solid with optimum physical properties takes place as follows: Increasing temperature causes increasing solvation of the resin particles with a commensurate viscosity increase.When the liquid plasticizer is absorbed by the resin particles solidification occurs. This stage is referred to as the gel point or gelation temperature. This temperature is controlled by choice of compound ingredients, mainly resin and plasticizer.