One-Component Polyurethane Adhesives Solvent-Free

The main component of these adhesives consists of pre-crosslinked, high molecular weight polyurethanes. These prepolymers (Section 2.1.3) exist in a liquid or paste-like state and still show free isocyanate groups (so-called polyisocyanate-polyurethane). With these isocyanate groups the -O-H group 

Component A PUR prepolymer with reactive isocyanate groups 

Since these one-component polyurethane adhesives cure through reaction with water, one talks of moisture curing one-component polyurethane adhesives. Their characteristic feature is their excellent adhesiveness. Apart from adhesive applications, these formulations are applied to a great extent as sealing compounds, for example, as fitting foam glue or PU-foam (Section 4.9). 

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