impregnation

in polymer chemistry
https://doi.org/10.1351/goldbook.IT07246
Penetration of monomeric, oligomeric, or polymeric liquids into an assembly of fibres.
Notes:
  1. The term as defined here is specific to polymer science. An alternative definition of 'impregnation' applies in some other fields of chemistry.
  2. Impregnation is usually carried out on a woven fabric or a yarn.
Source:
PAC, 2004, 76, 1985. 'Definition of terms related to polymer blends, composites, and multiphase polymeric materials (IUPAC Recommendations 2004)' on page 1991 (https://doi.org/10.1351/pac200476111985)