The internal plasticizer is actually a part of the polymer. Generally, the internal plasticizer is the second monomer introduced during the polymerization of the polymer. Because the second monomer * * * is aggregated in the molecular structure of the polymer, the regularity of the polymer molecular chain is reduced, that is, the crystallinity of the polymer molecular chain is reduced. For example, vinyl chloride-vinyl ester copolymer is softer than vinyl chloride homopolymer. The use temperature range of internal plasticizer is relatively narrow, and it must be added in the polymerization process, so the internal plasticizer is used less. ?

External Plasticizer External Plasticizer is a low molecular weight compound or polymer. Adding it to the polymer that needs plasticization can increase the plasticity of the polymer. External plasticizer is generally a liquid with high boiling point and difficult to volatilize or a solid with low melting point, and most of them are ester organic compounds. Usually, they do not react chemically with polymers, and the interaction with polymers is mainly swelling at elevated temperature, forming a solid solution with polymers. External plasticizer has comprehensive performance, convenient production and use, and is widely used. Now people generally refer to plasticizers as external plasticizers. Dioctyl phthalate (DOP) and dibutyl phthalate (DBP) are both external plasticizers.

ATBC

is a colorless and odorless oily liquid, with a boiling point of 343℃(.11MPa), a flash point (open cup) of 24℃, a freezing point of -8℃ and a volatilization rate of .9g/cm2? H(15℃), hydrolysis rate of .1%(1℃, 6 hours), soluble in most organic solvents, insoluble in water. Compatible with PVC, polystyrene, vinyl chloride-vinyl acetate polymer, nitrocellulose, cellulose acetate, polyvinyl butyral and other resins. Compatible with cellulose acetate and cellulose acetate butyrate. The cold resistance and light resistance of this product are similar to those of tributyl citrate, but the water resistance is better. Non-toxic, LD5=4mg/kg. ?

? This product is a non-toxic plasticizer, which can be used as plasticizer for PVC, cellulose resin and synthetic rubber. Used for non-toxic PVC granulation, food packaging containers, children's toys, medical products, films, plates, cellulose coatings and other products. It can also be used as a stabilizer for polyvinylidene chloride. ?

it seems to be external = = uncertain? Let's ask a professional =? =