The present invention relates to a composition in the form of a mixture comprising at least two components a) and b), wherein component a) comprises at least one mono and/or multifunctional thiol and component b) comprises at least one mono and/or multifunctional ene, wherein the molar ratio between the thiol groups and the ene groups is 1:0.1 to 1:100. Further, the invention relates to an impregnated wood element, wherein it is obtainable by impregnating a wood element with a composition according to the present invention or a mixture of the components of the composition in batch form (multi-component) according to the present invention and thereafter curing the composition or the mixture. The invention also relates to a method of impregnating a wood element.