Polypropylene glycol/polymeric-MDI urethanes for bonding leather footwear materials

Abstract

Adhesive compositions based on polymeric-MDI and mixtures of polypropylene glycols and cured using the polymeric-MDI for bonding leather footwear material are reported. As a result of the polyfunctional nature of the polymeric-MDI, these compositions have only a limited shelf-life. Nevertheless, our studies show that satisfactory bond strengths are achievable for immediate bonding. Our investigation further indicates that the peel strength increases with decreasing molecular weight of glycols in the mixture and attains a maximum for compositions containing monomeric propylene glycol.

Keywords:

• Polymeric-MDI adhesive
• footwear materials
• short-chain segment interactions