Yes. Pentacryl will absorb all the way through the wood by soaking or brushing it on. The time it takes depends upon the type of wood and size of the piece. Keep in mind that most of the absorption is through the end grain. When using the brushing method, keep applying until the wood can no longer absorb Pentacryl.
In between brushing applications, the wood should be wrapped in plastic in order to help absorption and prevent premature evaporation of the moisture and Pentacryl. To prevent mold growth under the plastic, try to fully saturate your wood by brushing it on within 3-7 days. Remove the plastic when drying.