Evaluation of an ammonia‐free natural rubber latex adhesive

Abstract

Natural rubber latex (NRL) within the adhesives industry has had limited applications because of poor water and chemical resistance; additionally, conventional preservation methods with ammonia produce poor adhesive properties and introduce toxicity. Today, solvent‐based adhesives dominate the market because of their superior mechanical properties; however, they negatively affect the health of users depending on the application due to the toxic chemicals. In this study, we investigated using a novel NRL‐based ammonia‐free adhesive as primary materials with bio‐additives, specifically cellulose, and collagen, to enhance their mechanical property provide the industry with an adhesive safe to handle. The peeling strength of an ammonia‐free NRL, 60% dry rubber content (DRC) NRL, with cellulose and collagen (Industrial Adhesive) were compared to high‐performance adhesives used within the footwear and construction industry to prove these adhesives direct applicability within these industries. Our findings showed that the ammonia‐free NRL Industrial Adhesive exhibited superior mechanical properties when compared against resilient flooring adhesives and footwear adhesives. Additionally, the peeling strength of an ammonia‐free 35% DRC with only cellulose (Office Adhesive) was compared to PVA‐based Elmer's Glue and it was observed that the ammonia‐free NRL adhesive outperformed Elmer's Glue by almost reaching four times the peeling strength of Elmer's Glue.