Highly filled polyurethane compositions

Abstract

A moisture-curing composition containing a) 5 to 20 wt. % of at least one isocyanate-functional polymer, b) 7 to 20 wt. % of rapeseed oil methyl ester and c) 70 to 88 wt. % of at least one filler, based on the total composition. Compositions are suitable in particular as adhesive, sealant or coating, and preferably as a parquet adhesive or joint sealing material.

Claims

1. A moisture-curing composition comprising a) 5 wt % to 20 wt % of at least one isocyanate-functional polymer, b) 7 wt % to 20 wt % of rapeseed oil methyl ester, and c) 70 wt % to 88 wt % of at least one filler, based on the overall composition.

2. The moisture-curing composition as claimed in claim 1, wherein the at least one isocyanate-functional polymer is included with a fraction of 7 wt % to 20 wt %, based on the overall composition.

3. The moisture-curing composition as claimed in claim 1, wherein rapeseed oil methyl ester is included with a fraction of 8 wt % to 18 wt %, based on the overall composition.

4. The moisture-curing composition as claimed in claim 1, wherein the at least one filler is included with a fraction of 70 wt % to 80 wt %, based on the overall composition.

5. The moisture-curing composition as claimed in claim 1, wherein the at least one filler comprises a chalk.

6. The moisture-curing composition as claimed in claim 1, wherein the composition additionally comprises at least one latent curing agent, and/or at least one drying agent, and/or at least one catalyst, in a total fraction of 5 wt %, based on the overall composition.

7. The moisture-curing composition as claimed in claim 1, comprising a) 9 wt % to 16 wt % of at least one isocyanate-functional polymer, b) 10 wt % to 12 wt % of rapeseed oil methyl ester, c) 70 wt % to 77 wt % of at least one chalk, d) 0 wt % to 2 wt % of at least one latent curing agent, e) 0 wt % to 0.5 wt % of at least one catalyst, and f) 0 wt % to 2 wt % of at least one drying agent, based on the overall composition.

8. The moisture-curing composition as claimed in claim 1, wherein the composition before curing and after conditioning at 23 C. for 24 h has an extrusion force of 1600 N.

9. An adhesive, sealant or coating comprising the moisture-curing composition as claimed in claim 1.

10. A wood flooring adhesive comprising the moisture-curing composition as claimed in claim 1.

11. A sealant for joints comprising the moisture-curing composition as claimed in claim 1.

12. A fully cured composition obtained from a composition as claimed in claim 1 after curing thereof with water.

13. The moisture-curing composition as claimed in claim 1, wherein the at least one isocyanate-functional polymer has a remaining free isocyanate group content of from 0.1 to 5 wt %.

14. The moisture-curing composition as claimed in claim 1, wherein the rapeseed oil methyl ester acts as a plasticizer, and the composition contains no other plasticizer.

15. The moisture-curing composition as claimed in claim 1, wherein the the composition before curing and after conditioning at 23 C. for 24 h has an extrusion force of 1000 N.

Description

EXAMPLES

(1) Set out below are working examples which are intended to elucidate in more detail the invention described. The invention is of course not confined to these working examples described.

(2) Test Methods

(3) The tensile strength and the elongation at break were determined according to DIN 53504 (tensioning rate: 200 mm/min) on films with a layer thickness of 2 mm that have been cured for 7 days at 23 C. and 50% relative humidity.

(4) The Shore A hardness was determined according to DIN 53505, on specimens with a layer thickness of 6 mm that have been cured for 7 days at 23 C. and 50% relative humidity.

(5) The skin-over time (time to absence of tack, tack-free time) was determined at 23 C. and 50% relative humidity. For the determination of the skin-over time, a small portion of the adhesive at room temperature was applied to cardboard, in a layer thickness of approximately 2 mm, and a determination was made of the time until the surface of the adhesive first no longer left any residues on a finger used to lightly press the surface of the adhesive.

(6) For the determination of the extrusion force, the compositions were dispensed into internally coated aluminum cartridges (outer diameter 46.9 mm, inner diameter 46.2 mm, length 215 mm, metric ISO thread M151.5 mm) and given an airtight seal with a polyethylene stopper (diameter 46.1 mm) from Novelis Deutschland GmbH. After conditioning at 23 C. for 24 hours, the cartridges were opened and the contents extruded using an extrusion device. For this purpose, a nozzle with a 2 mm inside-diameter opening was screwed onto the cartridge thread. Using an extrusion device (Zwick/Roell Z005), a determination was made of the force needed to extrude the composition at an extrusion rate of 60 mm/min. The figure reported is an average value of the forces measured after an extrusion distance of 22 mm, 24 mm, 26 mm, and 28 mm. After an extrusion distance of 30 mm, measurement was halted.

(7) A second measurement series was implemented following storage of identical cartridges at 60 C. for 7 days each, followed by cooling of the cartridges to room temperature. These measurements for the extrusion force were carried out subsequently in the same procedure as for the first measurement series. This second measurement series was used to estimate the storage stability of the compositions.

(8) Preparation of Isocyanate-Functional Polymer P-1

(9) Under a nitrogen atmosphere, 5687 g of Acclaim 4200 polyol (Bayer MaterialScience AG, Germany), 712 g of Desmodur 44 MC L (Bayer MaterialScience AG, Germany), and 0.6 g of DABCO 33 LV (Air Products & Chemicals Inc., USA) were heated to 80 C. with continual stirring and were left at this temperature. After a reaction time of an hour, the free isocyanate groups content was found by titration to be 1.9 wt %.

(10) Preparation of Aldimine A-1

(11) Under a nitrogen atmosphere, 101.8 g (0.36 mol) of 2,2-dimethyl-3-lauryloxy-propanol, purified by distillation, were introduced into a round-bottom flask. With vigorous stirring, 20.0 g (0.35 mol of N) of 1,6-hexamethylenediamine (BASF; amine content 17.04 mmol N/g) were slowly added from a heated dropping funnel. In the course of the addition, the reaction mixture warmed up and turned increasingly cloudy. Following complete addition of the amine, the volatile reaction products were removed under reduced pressure (10 mbar, 80 C.), to give 115.4 g of a pale yellow oil having an amine content of 2.94 mmol N/g.

(12) Production of Compositions Z-1 to Z-8

(13) A vacuum mixer was charged, in accordance with the parts by weight (wt %) reported in table 1, with 3530 g of dried Omyacarb 40 GU chalk (Omya AG, Switzerland) with 500 g of the respective plasticizer (e.g., rapeseed oil methyl ester for example 1; see table 2 for a detailed list of the plasticizers used). Then 355 g of polymer P-1 were added, followed by 50 g of Additive TI (OMG Borchers GmbH, Germany) and 50 g of Desmodur CD-L (Bayer MaterialScience AG, Germany). Subsequently a further 400 g of polymer P-1 were added, followed by 100 g of aldimine A-1. Lastly 14 g of salicylic acid (5 wt % in DOA; DOA=bis(2-ethylhexyl) adipate; e.g., Eastman Chemical Company, USA) and 1 g of dibutyltin dilaurate (e.g.: Jacobson Chemicals Ltd., UK) were added. The mixer was closed and stirring took place under reduced pressure at 1000-1200 revolutions for 20 minutes, with processing to form a homogeneous paste having a total mass of 5000 g. This paste was then dispensed into internally coated aluminum gun-application cartridges.

(14) TABLE-US-00001 TABLE 1 Ingredients in parts by weight (wt %) of the inventive composition Z-1 and of the reference compositions Z-2 to Z-8. Z-1 Z-2 Z-3 Z-4 Z-5 Z-6 Z-7 Z-8 Omyacarb 40 GU 70.6 70.6 70.6 70.6 70.6 70.6 70.6 70.6 Polymer P-1 15.1 15.1 15.1 15.1 15.1 15.1 15.1 15.1 Rapeseed oil 10 methyl ester DIDP 10 DOA 10 EME-100 10 ETO-100 10 SNS-100 10 Hexamoll DINCH 10 Mesamoll 10 Aldimine A-1 2 2 2 2 2 2 2 2 Additive TI 1 1 1 1 1 1 1 1 Desmodur CD-L 1 1 1 1 1 1 1 1 DBTL 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 Salicylic acid 0.28 0.28 0.28 0.28 0.28 0.28 0.28 0.28 (5% in DOA)

(15) TABLE-US-00002 TABLE 2 Plasticizers used for producing compositions Z-1 to Z-8 by above production method. Plasticizer Manufacturer Z-1 Rapeseed oil methyl ester Oleon N.V., Belgium (RME) Z-2 DIDP (diisodecyl phthalate) ExxonMobil, USA Z-3 DOA (bis(2-ethylhexyl) adipate) Eastman Chem., USA Z-4 EME-100 (soybean methyl ester- Chimista Specialty Chem, USA based) Z-5 ETO-100 (pine oil ester-based) Chimista Specialty Chem, USA Z-6 SNS-100 (castor oil-based) Chimista Specialty Chem, USA Z-7 Hexamoll DINCH BASF SE, Germany Z-8 Mesamoll Lanxess AG, Germany

(16) TABLE-US-00003 TABLE 3 Test results of inventive composition Z-1 and of reference compositions Z-2 to Z-8 according to the methods described earlier on above. Z-1 Z-2 Z-3 Z-4 Z-5 Z-6 Z-7 Z-8 Tensile strength 0.61 0.86 0.98 0.57 0.63 0.87 0.95 0.94 [MPa] Elongation at 308 112 78 56 310 87 76 94 break [%] Shore A 49 56 60 50 53 57 58 58 Skin-over time 13 15 18 12 7 15 16 16 [min] Extrusion force [N] 858 2401 1527 1547 2370 2615 2118 2300 1 d RT (2 mm) Extrusion force [N] 819 2600 1450 1903 >3200 2709 2216 >3200 7 d 60 C. (2 mm)

(17) The inventive example Z-1 (see table 3) shows clearly that using rapeseed oil methyl ester as plasticizer in highly filled compositions with more than 70 wt % of filler, the extrusion force is well below 1000 N, even after storage of the cartridge at 60 C. for 7 days, which also suggests good storage stability. In comparison to this, all of reference examples Z-2 to Z-8 exhibit a much higher extrusion force, both in the fresh condition and after storage at 60 C. For a user-friendly product, however, extrusion forces as low as possible are desirable. At the same time, it is clear from the data in table 3 that the inventive composition Z-1 in the cured state, in terms of mechanical values (tensile strength, elongation at break, Shore A), suggests a suitability as adhesive and sealant.

(18) Production of Compositions Z-9 to Z-14

(19) These inventive compositions were produced while varying the quantity of filler, the quantity of the rapeseed oil methyl ester and/or of the polymer P-1. The overall mass of the individual compositions, however, was likewise adjusted to 5000 g in each case. A vacuum mixer was charged, in accordance with the parts by weight (wt %) recorded in table 4, with dried Omyacarb 40 GU chalk (Omya AG, Switzerland) with rapeseed oil methyl ester. Then in each case half of polymer P-1 was added, followed by 50 g of additive TI (OMG Borchers GmbH, Germany) and 50 g of Desmodur CD-L (Bayer MaterialScience AG, Germany). Thereafter the second half of polymer P-1 was added, followed by 100 g of aldimine A-1. Lastly, 14 g of salicylic acid (5 wt % in DOA; DOA=bis(2-ethylhexyl) adipate; e.g., Eastman Chemical Company, USA) and 1 g of dibutyltin dilaurate (e.g.: Jacobson Chemicals Ltd., UK) were added. The mixer was closed and the contents were stirred under reduced pressure at 1000-1200 revolutions for 20 minutes and processed to give a homogeneous paste having a total mass of 5000 g. This paste was then dispensed into internally coated aluminum gun-application cartridges.

(20) TABLE-US-00004 TABLE 4 Ingredients in parts by weight (wt %) of inventive compositions Z-9 to Z-14 and results of the measurements for extrusion force, in accordance with the method described earlier on above. Z-9 Z-10 Z-11 Z-12 Z-13 Z-14 Omyacarb 40 GU 70.6 70.6 70.6 72.6 74.6 76.6 Polymer P-1 16.1 17.1 18.1 13.1 11.1 9.1 Rapeseed oil 9 8 7 10 10 10 methyl ester Aldimine A-1 2 2 2 2 2 2 Additive TI 1 1 1 1 1 1 Desmodur CD-L 1 1 1 1 1 1 DBTL 0.02 0.02 0.02 0.02 0.02 0.02 Salicylic acid 0.28 0.28 0.28 0.28 0.28 0.28 (5% in DOA) Extrusion force [N] 982 1241 1590 866 907 994 1 d RT (2 mm) Extrusion force [N] 985 1232 1482 960 1089 1110 7 d 60 C. (2 mm)

(21) The inventive compositions Z-9 to Z-14 (see table 4) show the influence of the individual constituents on the extrusion force. Composition Z-14 in particular, with 76.6 wt % of chalk, based on the overall composition, exhibits strikingly low extrusion forces in view of the high filler content.