Development an‎d Modification of Ethylene–Vinyl Acetate (EVA)-Based Hot-Melt Adhesives for PVC to Steel Adhesion

10/11/2026 12:00:00 AM

Hot-melt adhesives based on ethylene-vinyl acetate (EVA) copolymer have gained a special place in various industries in recent decades due to their easy processability, good heat resistance an‎d flexibility. However, their application in bonding to metal surfaces has been limited due to the mainly non-polar nature of EVA. The aim of this study was to modify the EVA formulation using chlorinated polyethylene (CPE) an‎d adhesion promoter resin (tackifier) ​​in order to improve the polymer-metal adhesive bonding performance. In this regard, EVA/CPE blends were prepared in five weight ratios including 100/0,90/10, 80/20, 70/30 an‎d 50/50 in the presence of 10% by weight of tackifier resin by melt mixing method. The resulting samples were subjected to FTIR, DSC, contact angle an‎d mechanical tests (tensile strength, 180° peel an‎d overlap shear). The results showed that increasing CPE improved the adhesive bonding properties. The pure EVA sample containing Caliphon withstood a maximum force of about 336 N in the overlap shear test, while this value reached about 433 N in the 70/30 sample. The 180° peel force also increased from about 20 N to about 45 N. The elongation at break in the tensile test decreased from about 71% in the pure EVA containing Caliphon to about 55% in the 70/30 blend, indicating an increase in stiffness an‎d better ability to transfer stress in the bonding area. The decrease in contact angle from 92° in the pure EVA to 68° in the 70/30 blend indicated improved wettability an‎d increased surface energy. The DSC results indicated significant thermal changes due to the presence of CPE. The melting temperature (Tm) of pure EVA was measured to be around 70°C, while a decrease of several degrees was observed in the 70/30 blend. The glass transition temperature (Tg) also changed from around -30°C to around -14°C, indicating an increase in the proportion of the crystalline phase an‎d a decrease in flexibility at low temperatures. Overall, this study showed that modifying EVA by adding chlorinated polyethylene an‎d a tackifier resin significantly improved mechanical properties, increased surface wettability, an‎d enhanced thermal properties. The 70/30 EVA/CPE formulation in the presence of 10% tackifier was identified as the optimal blend an‎d was able to largely overcome the inherent limitations of EVA in bonding to metal surfaces.

چسب گرما ذوب , اتيلن وينيل استات , پلي اتيلن كلرينه شده , چسبندگي پي وي سي به استيل , اصلاح فرمولاسيون

hot melt adhesive , Ethylene vinyl acetate(EVA) , Chlorinated polyethylene(CPE) , PVC adhesion to steel , Formulation modification

Zahra Akbari

Mohamadreza Moghbali