Plasticizers
Additives > Lubricants
| Plasticizers | ||
The flexibility, ductility and toughness of polymers can be improved with the help of additives called plasticizers. Their presence also reduces the hardness and fragility. Plasticizers usually have low vapor pressure and low molecular weight. The plasticizer penetrates the interior of the polymer mass and separates the chains, thus reducing the forces of attraction between them. The addition of small molecules of plasticizer, with flexible chains, implies a large amount of free volume. Plasticizers lower the glass transition temperature and in this way polymers can be used at room temperature in applications that require a certain degree of flexibility and ductility. The molecules of a highly crosslinked polymer are held together by covalent bonds, which do not allow the plasticizer to separate the chains from each other. In the case of a highly crystalline polymer, the association forces are almost as strong as the covalent bonds, so the effect is similar to the previous case. |  | |
| Commons Plasticizers | ||
|  | |