Function of Plasticizers in Film Formation

The amount of plasticizer added can cause adverse effects on film properties such as increasing mass transfer through the films. Hence, plasticizers must 

Chitosan and several of its innumerable derivatives have the ability to form thin membranous films of use in packaging [254-256], encapsulation and drug delivery systems. Due to drug polymer interactions, high viscosity chitosan films showed better sustainable release and the mechanism of release followed Fickian diffusion control with subsequent zero order release [257]. 

A novel organic (chitosan) and inorganic (tetraethyl orthosilicate) composite membrane has been prepared, which is pH sensitive and drug permeable [258]. The latter possibly involved in ionic interactions. By plasma source ion implantation technique, the adhesion between linear low-density polyethylene and chitosan could be improved [259]. Such bilayer films showed 10 times lower oxygen permeability, a property of use in food packaging applications. These multilayer films were easily recyclable. 

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