COATING SYSTEM HAVING HIGH SURFACE ROUGHNESS

Abstract

A polyurea composition including a first component A with at least one isocyanate-functional polyurethane polymer P1 and a second component B including a blocked amine BA and optionally a polyamine PA having a molecular weight in the range from 60 to 500 g/mol. The polyurea composition further includes a silane S1 selected from the list consisting of isocyanatosilanes S1-1 and epoxy silanes S1-2 as well as an aminosilane S2 and an aggregate AG of an at 23° C. solid thermoset. The polyurea composition is notable for high surface roughness and for reliable and long-term bonding of the aggregates to the coating with no need for sealing. Further, the polyurea composition has enough adhesion to the substrate that the application of a primer layer on the substrate prior to application is not necessary.

Claims

1. A polyurea composition comprising: a first component A comprising; at least one isocyanate-functional polyurethane polymer P1; a second component B comprising; at least one blocked amine BA which has a blocked, hydrolytically activatable amino group and either at least one further blocked, hydrolytically activatable amino group or at least one reactive group R which is selected from the group consisting of hydroxyl group, mercapto group and secondary amino group; wherein the polyurea composition further comprises: at least one silane S1 selected from the list consisting of isocyanatosilanes S1-1 and epoxy silanes S1-2; at least one aminosilane S2; at least one aggregate AG of an at 23° C. solid thermoset; wherein the weight ratio between S1/S2 is >2, and the total amount of the sum of (S1+S2) is 2-6 wt. % based on the total amount of the polyurea composition.

2. The polyurea composition as claimed in claim 1, wherein the polyurethane polymer P1 is prepared from polyols that are a mixture of at least one diol chain extender and polyoxyalkylene polyols.

3. The polyurea composition as claimed in claim 1, wherein the blocked, hydrolytically activatable amino group of the blocked amine BA is an aldimino group.

4. The polyurea composition as claimed in claim 1, wherein the second component B further comprises at least one polyamine PA having a molecular weight in the range from 60 to 500 g/mol.

5. The polyurea composition as claimed in claim 1, wherein the epoxy silane S1-2 is 3-glycidyloxypropyltrimethoxysilane.

6. The polyurea composition as claimed in claim 1, wherein the isocyanatosilane S1-1 is 3-Isocyanatopropyltrimethoxysilane.

7. The polyurea composition as claimed in claim 1, wherein the aminosilane S2 is 3-Aminopropyltrimethoxysilane.

8. The polyurea composition as claimed in claim 1, wherein the weight ratio between S1/S2 is 2.05-3.5.

9. The polyurea composition as claimed in claim 1, wherein the total amount of the sum of (S1+S2) is 2.75-4.5 wt. % based on the total amount of the polyurea composition.

10. The polyurea composition as claimed in claim 1, wherein the at 23° C. solid thermoset is selected from the list consisting of polyallyl diglycol carbonate, styrene acrylonitrile, cross linked polyvinyl chloride, and cross linked urea formaldehyde.

11. The polyurea composition as claimed in claim 1, wherein the polyurea composition contains less than 5 wt. % of at least one inorganic aggregate AZ.

12-14. (canceled)

15. A method for producing a coating with a polyurea composition as claimed in claim 1, the method comprising the following method steps: a) mixing the first component A with the second component B, b) applying the resulting mixed polyurea composition to a substrate, and c) curing the applied polyurea composition.

Description

EXAMPLES

[0130] Given below are working examples which are intended to further elucidate the invention described. Of course, the invention is not confined to these working examples described.

[0131] Commercial Substances Used: [0132] Propylene carbonate Propylene carbonate (solvent) [0133] 1,4 butanediol 1,4 butanediol [0134] Polyether triol Polypropylene oxide-based triol, Mw: 3'000 g/mol, [0135] Catalyst 1 Dibutyltin dilaurate (DBTL) [0136] IPDI IPDI Monomer, Mw: 222.3 g/mol [0137] TiO.sub.2 Titanium dioxide, pigment [0138] Catalyst 2 Ethylacetoacetate titanate [0139] Deformer Defoaming agent [0140] Ultra 8 ResNsand Ultra 8, aggregate of thermoset Polymer Resin (polyallyl diglycol carbonate), particle size 1680-2380 microns, specific gravity (H.sub.2O=1): 1.26, hardness (Rockwell, M-scale): M95-M110, R.J. MARSHALL COMPANY (MI, USA) [0141] Ultra 12 ResNsand Ultra 12, aggregate of thermoset Polymer Resin (polyallyl diglycol carbonate), particle size 1190-1680 microns, specific gravity (H.sub.2O=1): 1.26, hardness (Rockwell, M-scale): M95-M110, R.J. MARSHALL COMPANY (MI, USA) [0142] Silica sand Particle size=0.6-1.2 mm [0143] A-1110 3-Aminopropyltrimethoxysilane, Mw: 221.4 g/mol, aminosilane, Silquest® A-1110, Momentive Performance Materials, Germany [0144] A-187 3-Glycidyloxypropyltrimethoxysilane, Mw: 236.1 g/mol, epoxy silane, Silquest® A-187, Momentive Performance Materials, Germany [0145] A-Link 35 3-Isocyanatopropyltrimethoxysilane, Mw: 205.28 g/mol, isocyanatosilane, Silquest A Link 35, Momentive Performance Materials, Germany [0146] Polyamine PA Mixture of 3,5-diethyl-2,4- and -2,6-tolylenediamine, Lonzacure DEDTA 80 [0147] Blocked amine BA Amine with blocked aldimino group, Vestamin A 139, Evonik [0148] UV absorber 1 Hydroxyphenyl benzotriazole class, Tinuvin® 1130, BASF [0149] UV absorber 2 Hindered amine class, Tinuvin® 1130, BASF

[0150] Production and Application of the Mixed Polyurea Composition, and Methods of Testing:

[0151] In order to prepare the isocyanate-functional polyurethane polymer P1 of the component A, the relevant raw materials were heated to 70° C. and reacted for 2 hours. The remaining additives and pigments for the component A were added and mixed for 10 min using a cowles mixer.

[0152] The adhesion was measured at 23° C. by sandblasting a concrete surface. The mixed polyurea composition was applied with a thickness of 1.5 mm and a Flexitape (Sika® Flexitape Heavy, Sika Corporation USA, Flexitape was cut into 2.5 cm wide strips by 15.25 cm long) was fully embedded into the uncured composition. After 1 week at 23° C. the Flexitape was pulled by hand and the failure method was evaluated. If material was pulled/peeled off the substrate (adhesive failure) this was considered a “Failure”. When the sample showed cohesive failure between the composition and the substrate the result was rated “Passing”.

[0153] The abrasion was determined using a test equipment consisting of a compressed air operated machine (pressure ca. 5 bar) which moves a car wheel mechanically on the coating system under test and turns it on its axis.

[0154] The tyre is loaded at a weight of 400 kg and is turned at a maximum angle of deflection of 100° back and forth as 1 cycle. The tests are run so that the temperature on the coating surface does not rise above 65° C. Samples that showed no cracks, no aggregates broken out after the testing were labeled “no damages”. Samples that showed visible cracks and/or individual aggregates broken out after the testing were labeled “slight damages”.

[0155] Samples that showed larger ares without or completely removed coating after the testing were labeled “destroyed”.

[0156] The layer thickness of the coating was 1.4 mm

[0157] The crack bridging was determined according to ASTM C957-06.

[0158] “Pass” means no cracking

[0159] “Fail” means cracking

TABLE-US-00001 TABLE 1 composition 1 Composition 1 Raw material Wt.-% Component A Propylene carbonate 5.68 1,4 butanediol 0.89 Polyether triol 49.79 Catalyst 1 0.03 Catalyst 2 0.34 IPDI 14.87 TiO.sub.2 0.66 Deformer 0.71 Ultra 8 13.14 Ultra 12 5.63 Component B Polyamine PA 3.30 Blocked amine BA 3.30 UV absorber 1 0.83 UV absorber 2 0.83 Total 100.00

TABLE-US-00002 TABLE 2 adhesion testing, Composition 1 with addition of silanes Cohesive Compositions (added wt.-% of silane*) Failure E1 No silanes added Failure E2 1% A link 35 Failure E3 2% A link 35 Failure E4 3% A link 35 Failure E5 4% A link 35 Failure E6 1% A1110 Failure E7 2% A1110 Failure E8 3% A1110 Failure E9 4% A1110 Failure E10 1% A187 Failure E11 2% A187 Failure E12 3% A187 Failure E13 4% A187 Failure E14 A35 1%/A1110 1% Failure E15 A35 2%/A1110 1% Failure E16 A35 3%/A1110 1% Passing E17 A35 1%/A110 1%/A187 1% Failure E18 A35 1.5%/A110 1%/A187 1% Passing * = based on the total weight of the final composition

TABLE-US-00003 TABLE 3 crack bridging and abrasion testing, Compositions Crack bridging Abrasion Composition E18 but without Pass n.d. Ultra 8 and without Ultra 12. Composition E18 but Fail “slight damages” after replacement of Ultra 8 and 1000 cycles Ultra 12 with the same amount of silica sand Composition E18 Pass “no damages” after 5000 cycles n.d. = not determined