Two-component hot-melt adhesive

Abstract

A moisture-curing two-component composition consisting of a component A containing at least one polyoxyalkylene, polyolefin and/or polyacrylate prepolymer having at least one hydrolysable silane group and at least one solid inert additive selected from hydrocarbons, polyesters or polyamides, a component B containing at least one crosslinking compound for the prepolymers, and auxiliary substances and additives in one or both components, the component A and the two-component composition each having hot-melt adhesive properties.

Claims

1. A moisture-curing two-component composition consisting of: a component A containing at least one polyoxyalkylene, polyolefin and/or polyacrylate prepolymer having at least one hydrolysable silane group and 0.1 to 20 wt % relative to the weight of the composition of at least one solid inert additive comprising polyamide and optionally another compound selected from the group consisting of hydrocarbons, polyesters or both; and a component B containing at least one crosslinking compound for the prepolymer, component B having a viscosity of 5,000 to 800,000 mPas at 25 C.; and optionally auxiliary substances selected from the group consisting of resin, plasticizer, stabilizer, water-dissolving or water-absorbing substance, pigment, filler, thickening agent and combinations thereof; the two-component composition and component A each having hot-melt adhesive properties wherein the composition is free of metal catalyst and comprises a catalyst consisting of amine compounds and/or silane adhesion promoters with amino groups.

2. The two-component composition according to claim 1, characterized in that the inert additive has a softening point of 40 to 150 C.

3. The two-component composition according to claim 1, characterized in that component B contains 0 to 30 wt. % of one or more silane-crosslinkable compounds, 2 to 60 wt. % of water-absorbing substances, 10 to 60 wt. % of auxiliary substances and additives, 0.5 to 15 wt. % of water, wherein the sum is 100%.

4. An adhesive for bonding glass, metal, ceramic, wood and/or plastic substrates comprising the two-component composition according to claim 1.

5. The moisture-curing composition of claim 1 wherein the composition is a hot melt adhesive and component B comprises water and a material having solubility or absorption capacity for water, wherein component B having a viscosity of 20,000 to 800,000 mPas at 25 C.

6. The moisture-curing composition of claim 1 wherein the composition is a hot melt adhesive and a weight ratio of component A to component B ranges from 10 parts A to 3 parts B to 10 parts A to 0.1 parts B.

7. The moisture-curing composition of claim 1 wherein the composition is a hot melt adhesive and components A and B are maintained separately and mixed before use while component A is in a molten state.

8. The moisture-curing composition of claim 1 wherein the composition is a hot melt adhesive and components A and B are maintained separately and mixed before use while component A is in a molten state and the mixed adhesive has a melting point above 25 C. and will solidify without crosslinking below 25 C.

9. The two-component composition according to claim 1, being free of optional auxiliary substances.

10. The two-component composition according to claim 1, wherein the crosslinking compound in component B contains water and/or silane-crosslinkable compounds.

11. The two-component composition according to claim 1, wherein the crosslinking compound in component B contains up to 15 wt. % of water and/or up to 30 wt. % of silane-crosslinkable compounds.

12. An adhesive comprising the two-component composition according to claim 1.

13. Cured reaction products of the two-component composition according to claim 1.

Description

EXAMPLES

Example 1: (Amounts in Parts by Weight)

(1) TABLE-US-00001 Component A Component B Silane-modified prepolymer 33 Plasticizer 1 9 Plasticizer 2 51 Stabilizer 0.5 Rheological auxiliary agent 3 10% tylose solution in water 0 10 Titanium dioxide 5.6 Chalk 40.1 39 Light stabilizer 0.1 Solid additive 5.6 Desiccant 1.5 Adhesion promoter 1.6
Plasticizer 1: Mesamoll
Plasticizer 2: PPG, Acclaim 6300
Stabilizer: Tinuvin 770
Desiccant: VTMO silane
Adhesion promoter: AMMO silane
Rheological auxiliary agent: Disparlon 6500
Solid additive: Arkon P125 (solid hydrocarbon resin)
Prepolymer: Geniosil STP-E30
Chalk: Socal U1S1

(2) Before being applied, components A and B are mixed in a static mixer at 70 C. in a proportion A:B of 10:1. The mixture is applied immediately. After 48 hours the composition has cured and has developed its final mechanical properties.

(3) Comparison:

Example 1: Two-Component Hot-Melt Adhesive

Comparative Example 2: One-Component Hot-Melt Adhesive from WO 2010/108716, Example 1

Comparative Example 3: Commercial Two-Component System in Paste Form

(4) TABLE-US-00002 Comparative Comparative Example 1 example 2 example 3 Position tack/300 g + + Position tack/1000 g + + Shear strength 2 hours >1 MPa 0.1 MPa 0.7 MPa Shear strength 14 days 2.5 MPa 2.5 MPa 2.5 MPa
Shear strength in accordance with ISO 4587,
Aluminum 99 substrate, 20252 mm
2 hours at 23 C./50% relative humidity, or
14 days at 23 C./50% relative humidity.
Test at 23 C., 50 mm/min
Initial Strength (Position Tack):

(5) The adhesive is applied (2 mm thick) to a cleaned, rigid substrate (Al metal) and adhesively bonded to a second substrate of the same type immediately thereafter. The adhesively bonded surface area is 10015 mm.

(6) After a waiting time of 5 minutes one substrate part is suspended vertically and the weight (300 g or 1000 g) is attached to the other. The time until the substrate slides off determined. The test is performed at 23 C.

(7) In the case of liquid-viscous adhesives the second substrate slides off after 10 seconds. In the case of hot-melt adhesives (one-component) no rapid shear strength is established. In the case of the example according to the invention both tests are better than in the comparative experiments.