the present invention is a method to produce novel composites based on microcapsules or microspheres embedded in contiuous polymeric matrices . both non - bioerodible and erodible polymers can be used . material can be incorporated into the microcapsules or microspheres for subsequent release . in one embodiment of the present invention , spheres are homogeneously dispersed in a polymer matrix and then forced to release their contents by exposure to temperature , light or ultrasound . alternatively , polymers which degrade as a function of time or hydrolysis can be used for controlled releases . the polymer composites have completely different properties from either a continuous polymer matrix or microcapsules or microspheres and are therefore useful for a wide variety of applications . when carbon tetrachloride is the incorporated material , the film is useful as a flame retarding device . when foaming agents are used , especially uv or heat sensitive materials , gas can be evolved inside each capsul the government has rights in this invention pursuant to grant number 5 - r01 - gm26698 awarded by the department of health and human services .