Many manufactured articles are made of composite materials often bonded by a phenolic resin. Through a D-optimal design. we optimized a method to characterize phenolic resins after the extraction process by GC-MS analysis. The study was conducted on three different phenolic resins and four manufactured articles with the same inorganic composition and different analyzed binders. https://parisnaturalfoodes.shop/product-category/promasil-milk-chocolate/