You understand the mechanism of action of the plasticizer of PVC films agriculture do?
PVC plastic sheeting purpose plasticizer is added
PVC plastic sheeting were added plasticizer has two purposes:
Reduce the viscous flow temperature of the polymer, making it easy molding,
Reduce soft temperature, increase cold resistance, it has a softness and flexibility in use.
Plasticizers solvent having a similar effect, but the more volatile solvents and can not maintain its properties. Plasticiser and solvent, high molecular weight, low volatility, which is different from the solvent.
Plasticizers for PVC plastic sheeting mechanism
Linear polymer molecular chains are mutually binding force, so preventing the molecular motion of the polymer chain, and hard to maintain state, not deformed. For ease of molding, make it soft and low temperature, we must first try to make this binding force is weakened.
In PVC example as follows: each part of the molecular chain of the polyvinyl chloride, in the presence of chlorine atoms occurs partially polarized, this time due to electrostatic attraction of the molecule chains. In this case, such as heating, the thermal motion of the molecular chain intensified, so that the force between the molecular chains is reduced, the gap increases. Then the plasticizer molecules into the molecular chain, molecular chain polar part of the polarized component with a plasticizer combined with each other. After cooling, the plasticizer remains in the original location, close to each other and hinder the molecular chain, resulting in the molecular chains move easily into the soft PVC products.
The molecular structure of the plasticizer is generally composed of two parts: the part of the polar part, the other part of the non-polar. Wherein the polar part may be combined with the polymer chains, the non-polar portion of the polymer chains do not work, just as a barrier between the molecular chains, resulting in weakening the forces between the polymer chains, thereby enhancing the activity of the molecular chain of the polymer becomes soft. Dioctyl phthalate (DOP) as an example, since octyl phthalate polymers and dipole interactions, benzene nucleus is polarized, so this part is easy and polymer. Nonpolar portion of a methine chain polar effect, and thus weak intermolecular interaction, upon deformation of the polymer molecular chains to move easily.On the other hand, <a href="http://www.greenmax-machine.com/eps-compacting.html"> Polystyrene compactor</a> and <a href="http://www.greenmax-machine.com/eps-hot-melt.html"> Styrofoam densifier</a> is necessary.