| 摘要 |
The hotmelt adhesive according to the invention contains A) at least one polyurethane prepolymer of a) at least one polyisocyanate, more particularly toluene diisocyanate and/or MDI, b) at least one polyalkylene glycol in a concentration of more than 10% by weight, based on the hotmelt adhesive as a whole, more particularly polypropylene glycol, c) at least one polyester glycol, preferably at least two polyester glycols with different glass transition temperatures and d) at least one chain extender and B) optionally additives, such as e) a resin, more particularly a hydrocarbon resin, and f) a stabilizer, more particularly toluene sulfonyl isocyanate. The hotmelt adhesive preferably has a melt viscosity of 4 to 100 Pa.s at 170 DEG C. The PU prepolymer has only one Tg in the DSC curve. The hotmelt adhesive is distinguished by high creep resistance and high early and ultimate strengths. Accordingly, it is mainly used in the shoe industry, more particular, in application machines designed for application in the shoe production line which does not contain any steam-operated preliminary crosslinking stage or a drying tunnel. The hotmelt adhesive is preferably produced by a single-stage process. The adhesive is particularly suitable for fibrous materials, such as leather and textiles. |
