Abstract: The present disclosure relates to polymer particles comprising a polymer matrix having a coating of an inorganic semimetal oxide or metal oxide, wherein the polymer matrix has at least one first functional group A and at least one second functional group B, both functional groups A and B being able to enter into at least one covalent bond with one another, functional group A being selected from the group consisting of an azide group, C—C double bond, C—C triple bond, aldehyde group, ketone group, imine group, thioketone group and thiol group, and functional group B being selected from the group consisting of a C—C double bond, C—C triple bond, C—N triple bond, diene group, thiol group and amine group.