**Synthesis and Characterization of Modified Phenol-Formaldehyde Resin**
**1. Introduction**
Phenol-formaldehyde resin (PF resin) is a thermosetting polymer widely used in adhesives, coatings, and composite materials due to its excellent mechanical properties, thermal stability, and chemical resistance. However, the performance of PF resin can be enhanced by modifying its structure through the incorporation of other functional groups or the use


