English to German Tech/Engineering Chemistry; Chem Sci/Eng Plastics, injection moulding

Context: Injection moulding

Each volumetric unit of molten plastic injected into the cavity will shrink when surface tension forces are adjusted during cooling, and stresses will be built up in the solid part. These conditions can be alleviated by creating ***entrained*** gases in the molten plastic. The ***entrained*** gases will act as a lubricator because they change the fluidity of the melt and decrease the injection pressure which is necessary to inject the molten plastic into the cavity.

Any ideas what "entrained" means in this context and how it can best be rendered in German? Many thanks in advance.