Preparation And Performance Of Two Kinds Of Modified Hot-melt Adhesive Based On Thermoplastic Polyurethane

Thermoplastic polyurethane?TPU?hot melt adhesive has been widely used because of its many excellent properties.According to the principle of similar compatibility,if the solubility parameter is close,the compatibility is good.In this paper,thermoplastic polyurethane?TPU?,polyethylene?PE?,ethylene vinyl acetate?EVA?are used as the main component of the hot melt adhesive.Mixer is used to explore suitable materials ratio,temperature and other conditions and prepare two kinds of thermoplastic polyurethane as the main materials of modified hot melt adhesive.The tensile strength,elongation at break,modulus of elasticity,peel strength were tested by Electronic tensile testing machine.The micro-structure was characterized by SEM and FTIR.The hardness,thermos stability of the material were investigated also.The first system was constituted by TPU/PE,TPU/PE/polyethylene wax,TPU/PE/polyethylene wax/nanoCaCO₃,TPU/PE/polyethylene wax/nanoCaCO₃/138 rosin resin,TPU/PE/polyethylene wax/nanoCaCO₃/terpene resins,TPU/PE/polyethylene wax/nanoCaCO₃/138 rosin resin/terpene resins.A certain amount of antioxidant 1010 was added in the system.The mixing parameters were 140?/30 rpm/7 min.The second system was component forms by TPU/EVA,TPU/EVA/nanoCaCO₃ and TPU/EVA/nanoCaCO₃/terpene resins.A certain amount of antioxidant 1010 was added in the system.The mixing parameters was 130?/30 rpm/7 min.Specific content as follows:The first system:?1?In the study of double component,along with the increase of the content of PE,The elongation at break and modulus of mixture generally showed a trend of decline after rising first,hardness generally showed a trend of decline,peel strength after rising first overall downward trend.?2?The micro test methods of infrared and SEM showed that along with the addition of the third component polyethylene wax,within a certain range to promote the compatibility of TPU and PE blending effect.Otherwise,thermogravimetric analysis showed that the addition of polyethylene wax could increase weightlessness temperature of the material,improve the thermal stability of materials.?3?After adding nanoCaCO₃,the tensile strength of the blending system was slightly lower,but rigidity and peel strength had improved significantly.By adding three kinds of viscosity resin as 138 resin rosin,terpene resin and terpene/138 resin rosin,the results indicated that mixed viscosity resin?terpene/138 resin rosin?showed a better comprehensive mechanical performance.When the proportion is TPU/PE/polyethylene wax/nanoCaCO₃/138 rosin resin:terpene resin=32/8/4/4/7/3,they have with optimum performance values,the peel strength of the materials is 6.35 N/mm.The second system:?1?In double component,the elongation at break and peel strength of the mixture generally presented the downward trend after rising first,elastic modulus presented the downward trend,hardness presented an increasing tendency on the whole along with the increase of the content of EVA.The micro test methods of FTIR and SEM showed that TPU had good compatibility with EVA.Thermogravimetric analysis?TGA?showed that thermal-stability of TPU could be improved by adding EVA.?2?After adding nanoCaCO₃,the tensile strength of the blending system was slightly lower,but rigidity and peel strength had improved significantly.After adding terpene resin,peel strength could get a significant improvement.When the proportion is TPU/EVA/nanoCaCO₃/terpene resin=32/8/2/3,they have with optimum performance values,the peel strength of the material is 7.11 N/mm.