Thermal, mechanical and adhesion properties of Polyurethane reactive hot melt adhesives prepared using bio-based 1,3-propanediol and 100 % renewably-sourced poly(trimethylene ether) glycol

摘要

A series of Polyurethane (PU) reactive hot melt adhesives (RHMAs) were prepared from 4,4'-diphenylmethane diisocyanate (4,4'-MD) reacted with poly(l,3-propylene alkanedicarboxylate) diols of different chain lengths, and combined with 100 % renewably-sourced polytrimeth-ylene ether glycol (P03G) or poly(oxypropylene) glycol (PPG). The morphology and adhesion properties of these PURHMAs were investigated using differential scanning calorimetry (DSC), dynamic mechanical thermal analyzer (DMA) and tensile testing. PURHMAs prepared with the two different polyether diols, P03G and PPG, generate significantly different values for glass transition temperature, crystallinity properties, open time, and bulk tensile strength. The resultant PURHMAs prepared from polyd ,3-propylene alkanedicarboxylate) and sustainably-derived P03G exhibit excellent adhesion properties to multiple substrates including plastics (PC, ABS) and metals (aluminum, steel), which is comparable to or better than those prepared from polyd ,6-hexamethylene adipate) diol (PHA) or PPG.