Influence of structural differences of hot-melt adhesive on peel strength of heat shrinkable sleeves

By means of infrared spectroscopy and differential scanning calorimeter technology, the difference between structures and compositions of hot-melt adhesives in 3 typical heat shrinkable sleeves used at home and abroad is analyzed to test the shear resistance and softening point of ring ball of adhesives. The influence of composition and structural differences of the adhesives on peel performance of heat shrinkable sleeves from PE of the main pipe is studied. Results show that there are great differences in composition and structure of hot-melt adhesives used for heat shrinkable tape products at home and abroad, and foreign adhesives have better shear performance and peel strength than domestic products, especially at high temperature. The analysis of chemical composition of hot melt adhesive shows that the differences in composition and structure are the main reason in influencing the shear and peel performance of heat shrinkable sleeves, and the performance difference, to a large extent, is that domestic hot-melt adhesive contains a lot of low melting point tackifying resin but lack of high melting point components. The recommendation is proposed in field peel performance test methods of heat shrinkable sleeves, improvement of assessment indicators, and study methods for long-term adhesive properties of heat shrinkable sleeves.