How do C5, C9, and DCPD petroleum resins differ in performance for adhesives and coatings?

How do C5, C9, and DCPD petroleum resins differ in performance for adhesives and coatings?
C5 petroleum resins offer high peel adhesion, fast tack, stable bonding, moderate melt viscosity, and good heat resistance, making them a cost-effective replacement for natural tackifiers like rosin and terpene resins in hot-melt adhesives and pressure-sensitive tapes. C9 aromatic resins provide excellent acid, alkali, and water resistance but have poorer adhesion and higher brittleness, so they are rarely used alone. DCPD cycloaliphatic resins bridge the gap, offering low odor, good transparency, and superior weather resistance for outdoor applications like road-marking paints and packaging adhesives. C5/C9 copolymers combine aliphatic and aromatic character, improving compatibility with EVA and broadening solvent solubility. The choice ultimately balances softening point, color, compatibility with base polymers, and cost.