| A hot melt adhesive is defined as an adhesive applied from the melt and gains strength upon solidification and crystallization. Hot melt adhesives are applied without solvent. The increase in solvent emission regulations has increased the demand for hot melt adhesives. However, with the general purpose hot melt adhesive, the material is applied as a thermoplastic melt and the resulting adhesive is also a thermoplastic. Therefore, creep is a major problem. And they are also susceptible to water permeation and /or solvent penetration. Many of the problems associated with hot melt adhesives can be eliminated or ameliorated if the hot melt was not a thermoplastic but rather a thermoset. Synthesizing a kind of curing hot melts (such as moisture-curable polyurethane hot melt adhesive) based on molecular design is just the purpose of the thesis, which can overcome the universal drawbacks existing in recent hot melts.The thesis systematically studied the synthesis and formulation of the moisture-curable polyurethane hot melt adhesive. By varying polyol types, polyol molecular weights, isocyanate index, two kinds of polyurethane pre-polymers with different set time were synthesized. Then, the formulation was optimized based on the fast-setting pre-polymer.Through the discussion of fillers, CA, EVA resin, tackifiers, wax, and stabilizer, the effects of the factors and their dosages on the performance of moisture-curable polyurethane hot melt adhesive were examined. Finally, the optimum formulation was determined by upright-crossing experiment design.In the end, the structure and heat-stability of obtained product were characterized and explained respectively by FTIR and DSC. The performance of the product was further confirmed.
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