CURABLE COMPOSITION OF LOW DENSITY

Abstract

A moisture-curing composition including a) at least one moisture-reactive polymer P with a proportion of 10% to 60% by weight, based on overall composition, b) at least one inorganic filler F with a proportion of at least 9% by weight, based on overall composition, c) between 3% and 25% by weight, based on overall composition, of at least one type of microscopic hollow beads H, wherein composition has density of less than 1.20 kg/l, and microscopic hollow beads H have compressive strength, measured to ASTM D3102-72, of at least 2.5 MPa, and microscopic hollow beads H have a volume-based particle size D90, measured by Coulter counter, of less than 100 μm.

Claims

1. A moisture-curing composition comprising a) at least one moisture-reactive polymer P in a proportion of 10% to 60% by weight, based on the total composition, b) at least one inorganic filler F in a proportion of at least 9% by weight, based on the total composition, c) between 3% and 25% by weight, based on the total composition, of at least one type of hollow microsphere H, wherein the composition has a density of less than 1.20 kg/L, preferably less than 1.10 kg/L, and the hollow microspheres H have a compressive strength, measured in accordance with ASTM D3102-72, of at least 2.5 MPa, and the hollow microspheres H have a volume-based particle size D90, measured with a Coulter counter, of less than 100 μm.

2. The moisture-curing composition as claimed in claim 1, wherein the hollow microspheres H are hollow glass spheres having a diameter of not more than 110 μm.

3. The moisture-curing composition as claimed in claim 1, wherein the at least one inorganic filler F is selected from the group consisting of precipitated or ground chalk, precipitated or fumed silica, titanium dioxide, or combinations of said fillers.

4. The moisture-curing composition as claimed in claim 1, wherein the moisture-reactive polymer P comprises at least one polyurethane polymer PU, wherein the polyurethane polymer PU has free or latent isocyanate groups and the composition in addition optionally comprises a latent curing agent for isocyanate groups.

5. The moisture-curing composition as claimed in claim 1, wherein the moisture-reactive polymer P comprises at least one silane-functional polymer STP.

6. The moisture-curing composition as claimed in claim 5, wherein the silane-functional polymer STP has end groups of the formula (II) ##STR00003## where R.sup.14 is a linear or branched monovalent hydrocarbyl radical having 1 to 5 carbon atoms; R.sup.15 is a linear or branched monovalent hydrocarbyl radical having 1 to 8 carbon atoms; x has a value of 0 or 1 or 2; R.sup.16 is a linear or branched divalent hydrocarbyl radical having 1 to 12 carbon atoms that optionally has cyclic and/or aromatic moieties and optionally one or more heteroatoms; and T is a divalent radical selected from —O—, —S—, —N(R.sup.7)—, —O—CO—N(R.sup.17)—, —N(R.sup.17)—CO—O— and —N(R.sup.17)—CO—N(R.sup.17)—, where R.sup.17 is a hydrogen radical or a linear or branched hydrocarbyl radical having 1 to 20 carbon atoms that optionally has cyclic moieties and that optionally has an alkoxysilane, ether or carboxylic ester group.

7. The moisture-curing composition as claimed in claim 1, wherein the composition additionally comprises at least one additive, wherein the additive is selected from the list consisting of plasticizers, curing catalysts, stabilizers, thixotropic agents, adhesion promoters, and desiccants.

8. The moisture-curing composition as claimed in claim 1, wherein the composition contains at least 25% by weight of inorganic filler F, based on the total composition.

9. The moisture-curing composition as claimed in claim 1, wherein the composition additionally contains between 1% and 25% by weight of carbon black, based on the total composition.

10. The moisture-curing composition as claimed in claim 1, wherein the composition comprises 9% to 15% by weight of inorganic filler F, based on the total composition, and also 5% to 15% by weight of hollow microspheres H, based on the total composition.

11. (canceled)

12. The moisture-curing composition as claimed claim 1, wherein the composition exhibits a fire retardancy class C as defined in DIN EN 13501-1 after curing.

13. (canceled)

14. A built structure or article of manufacture that has been bonded, sealed or coated with the moisture-curing composition as claimed in claim 1.

15. A cured composition of the moisture curing composition as claimed in claim 1.

Description

EXAMPLES

[0194] Working examples are presented hereinbelow, which are intended to further elucidate the invention described. The invention is of course not limited to these described working examples.

[0195] “Standard climatic conditions” refer to a temperature of 23±1° C. and a relative atmospheric humidity of 50±5%.

[0196] The tensile strength and the elongation at break were determined in accordance with DIN 53504 (tensile speed 200 mm/min) on films with a film thickness of 2 mm cured for 7 days at 23° C. and 50% relative atmospheric humidity.

[0197] For determination of the extrusion force, internally-coated aluminum cartridges (outer diameter 46.9 mm, inner diameter 46.2 mm, length 215 mm, opening 15-M) were filled with the compositions and sealed airtight with polyethylene stoppers (diameter 46.1 mm) from Novelis Deutschland GmbH. After conditioning at 23° C. for 24 hours, the cartridges were opened and the contents expressed by means of an expression device. For this, a nozzle having an orifice with an inner diameter of 3 mm was screwed onto the thread of the cartridge. An expression device (Zwick/Roell Z005) was used to determine the force needed to express the composition at an expression rate of 60 mm/min. The reported value is the average of the forces measured after an expression distance of 22 mm, 24 mm, 26 mm, and 28 mm. After an expression distance of 30 mm, the measurement was stopped.

[0198] The density of a sample was measured on a pycnometer with a volume of 100 mL that was thermally equilibrated at 23° C.

[0199] The theoretical density of a formulation was calculated on the basis of the proportions and density data of the raw materials.

[0200] For determination of the resistance to pumping, the density of a test formulation was first measured freshly after production and then a second time after an identical sample had been pumped through a drum pump with a pressure of bar (pressure peak at the metering stroke). A difference of 5% or less in the two density measurements indicates satisfactory resistance to pumping.

[0201] The thread formation in mm refers to the length of the sealant thread that remains after application of the sealant from an application gun after lifting the nozzle from the applied sealant bead. A relatively short thread is preferable.

[0202] Production of the Polymer P and of Thixotropic Agent 1

[0203] Production of the Silane-Functional Polymer STP-1

[0204] 1000 g of Acclaim® 12200 polyol (from Covestro; low monol polyoxypropylenediol, OH value 11.0 mg KOH/g, water content approx. 0.02% by weight), 43.6 g of isophorone diisocyanate (Vestanat® IPDI from Evonik Industries), 126.4 g of triethylene glycol bis(2-ethylhexanoate) (Solusolv® 2075 from Eastman Chem.), and 0.12 g of dibutyltin dilaurate were heated to 90° C. with exclusion of moisture and continuous stirring and maintained at this temperature until the content of free isocyanate groups as determined titrimetrically had reached a value of 0.63% by weight. 62.3 g of diethyl N-(3-trimethoxysilylpropyl)aminosuccinate (adduct of 3-aminopropyltrimethoxysilane and diethyl maleate; produced as described in U.S. Pat. No. 5,364,955) was then mixed in and the mixture was stirred at 90° C. until free isocyanate was no longer detectable by FT-IR spectroscopy. The silane-functional polymer was cooled to room temperature and stored with exclusion of moisture.

[0205] Production of Thixotropic Agent 1

[0206] A vacuum mixer was charged with 1000 g of hydrogenated diisononyl phthalate (Hexamol® DINCH, BASF) and 160 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, Bayer MaterialScience AG, Deutschland) and the contents were heated gently. 90 g of monobutylamine was then slowly added dropwise with vigorous stirring. The resulting white paste was stirred for a further hour under reduced pressure while cooling. Thixotropic agent 1 contains 20 parts by weight of this reaction product and 80 parts by weight of diisodecyl phthalate.

[0207] Production of the Moisture-Curing Compositions

[0208] Comparative examples are labeled “(ref.)” in Tables 2 to 5. The raw materials used are described in Table 1.

[0209] Raw Materials Used

TABLE-US-00001 TABLE 1 Raw materials used in the example formulations Raw material Manufacturer/Description Polymer STP-1 Silane-functional polymer; production see above. Plasticizer 1 Diisodecyl phthalate (Jayflex ® DIDP; Exxon Mobil) Plasticizer 2 Diisononyi cyclohexane-1,2-dicarboxylate (Hexamoll ® DINCH; BASF) Inorganic filler F1 Titanium dioxide (Kronos ® 2500; Kronos) Inorganic filler F2 Fumed silica (Cab-O-Sil ® M5; Cabot) Inorganic filler F3 Ground calcium carbonate (Omyacarb ® 5-GU; Omya) Carbon black Carbon black (Monarch ® 570; Cabot) (dried) Hollow Hollow spheres made of borosilicate glass, density: microspheres 0.15 kg/L, isostatic compressive strength: 2.1 MPa, H1 particle size D90: 105 μm, largest diameter: 115 μm (3M ® Glass Bubbles K15; 3M) Hollow Hollow spheres made of borosilicate glass, density: microspheres H2 0.25 kg/L, isostatic compressive strength: 5.2 MPa, particle size D90: 95 μm, largest diameter: 105 μm (3M ® Glass Bubbles K25; 3M) Hollow Hollow spheres made of borosilicate glass, density: microspheres H3 0.32 kg/L, isostatic compressive strength: 13.8 MPa, particle size D90: 80 μm, largest diameter: 85 μm (3M ® Glass Bubbles K32; 3M) Hollow Hollow spheres made of borosilicate glass, density: microspheres H4 0.28 kg/L, isostatic compressive strength: 21.0 MPa, particle size D90: 55 μm, largest diameter: 65 μm (3M ® Glass Bubbles S28HS; 3M) Hollow Hollow spheres made of aluminosilicate, microspheres H5 density 0.6-0.7 kg/L, particle size 50-180 μm (Aeropor ® 180, SH Minerals) Hollow Hollow spheres made of aluminosilicate, microspheres H6 density 0.7 kg/L, particle size 50-300 μm (Cenospheres ® , SH Minerals) Hollow Expanded hollow spheres made of thermoplastic microspheres H7 polymer, density 0.025 kg/L, compressive strength 1.2 MPa, particle size 35-55 μm (Expancel ® 461 DET d25, AkzoNobel) Thixotropic Urea derivative; production see above agent 1 Thixotropic Castor oil derivative (Thixatrol ® ST; Elementis) agent 2 Catalyst 1 Dibutyltin dilaurate (Sigma Aldrich) Desiccant Vinyltrimethoxysilane (Silquest ® A-171; Momentive) Adhesion N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane promoter (Silquest ® A-1110; Momentive) Stabilizer HALS light stabilizer (Tinuvin ® 770 DF; BASF)

TABLE-US-00002 TABLE 2 Compositions Z-1 to Z-4 in % by weight, in each case based on the total composition. Composition Z-1 (ref.) Z-2 Z-3 Z-4 Polymer STP-1 40.0 40.0 40.0 40.0 Stabilizer 0.3 0.3 0.3 0.3 Plasticizer 1 9.18 9.18 9.18 9.18 Desiccant 2.0 2.0 2.0 2.0 Inorganic filler F1 2.0 2.0 2.0 2.0 Thixotropic agent 1 25.0 25.0 25.0 25.0 Inorganic filler F2 2.0 2.0 2.0 2.0 Inorganic filler F3 6.5 6.5 6.5 6.5 Hollow microspheres H1 11.0 — — — Hollow microspheres H2 — 11.0 — — Hollow microspheres H3 — — 11.0 — Hollow microspheres H4 — — — 11.0 Adhesion promoter 2.0 2.0 2.0 2.0 Catalyst 0.02 0.02 0.02 0.02 TOTAL 100 100 100 100 Test results Extrusion force 683 580 569 552 (3 mm) [N] Thread formation [mm] 40 40 40 43 Tensile strength [MPa] 1.3 1.5 1.6 1.7 Elongation at break [%] 220 211 215 207 Density before pumping 0.64 0.79 0.85 0.84 [kg/L] Density after pumping 1.01 0.82 0.87 0.84 [kg/L] Resistance to pumping No Yes Yes Yes

TABLE-US-00003 TABLE 3 Compositions Z-5 to Z-8 and Z-18 in % by weight, in each case based on the total composition. Z-18 Composition Z-5 Z-6 Z-7 Z-8 (ref.) Polymer STP-1 40.0 40.0 40.0 50.0 40.0 Stabilizer 0.3 0.3 0.3 0.3 0.3 Plasticizer 1 9.27 9.27 9.27 15.95 17.7 Desiccant 2.0 2.0 2.0 0.5 2.0 Inorganic filler F1 2.0 2.0 2.0 — 2.0 Thixotropic agent 1 25.0 25.0 25.0 — 25.0 Inorganic filler F2 2.0 2.0 2.0 — 2.0 Inorganic filler F3 8.4 9.4 10.4 9.1 — Carbon black — — — 18.5 — Hollow microspheres H4 9.0 8.0 7.0 4.0 9.0 Adhesion promoter 2.0 2.0 2.0 1.5 2.0 Catalyst 1 0.03 0.03 0.03 0.15 0.02 TOTAL 100 100 100 100 100 Test results Extrusion force (3 mm) [N] 507 481 462 n/m 352 Thread formation [mm] 37 32 40 39 51 Tensile strength [MPa] 1.7 1.7 1.7 5.5 1.1 Elongation at break [%] 218 225 236 230 216 Density before pumping [kg/L] 0.88 0.91 0.93 1.06 0.82 Density after pumping [kg/L] 0.88 0.90 0.93 1.05 0.82 Resistance to pumping Yes Yes Yes Yes Yes “n/m” means that the value was not measured.

TABLE-US-00004 TABLE 4 Compositions Z-9 to Z-12 in % by weight, in each case based on the total composition. Composition Z-9 Z-10 Z-11 Z-12 Polymer STP-1 24.0 24.0 24.0 24.0 Stabilizer 0.3 0.3 0.3 0.3 Plasticizer 1 10.1 10.1 10.1 10.1 Desiccant 1 1.5 1.5 1.5 1.5 Inorganic filler F1 2.0 2.0 2.0 2.0 Thixotropic agent 1 20.0 20.0 20.0 20.0 Inorganic filler F3 37.0 33.0 29.0 25.0 Hollow microspheres H4 4.0 8.0 12.0 16.0 Adhesion promoter 1.0 1.0 1.0 1.0 Catalyst 1 0.1 0.1 0.1 0.1 TOTAL 100 100 100 100 Test results Extrusion force (3 mm) [N] 535 587 n/m n/m Thread formation [mm] 30 37 28 33 Tensile strength [MPa] 2.0 2.0 2.0 2.1 Elongation at break [%] 255 196 158 139 Density before pumping [kg/L] 1.17 1.01 0.90 0.81 Density after pumping [kg/L] 1.19 1.00 0.90 0.81 Resistance to pumping Yes Yes Yes Yes “n/m” means that the value was not measured.

TABLE-US-00005 TABLE 5 Compositions Z-13 to Z-17 in % by weight, in each case based on the total composition. Z-13 Z-14 Z-17 Composition (ref.) (ref.) Z-15 Z-16 (ref.) Polymer STP-1 17.5 17.5 21.0 21.0  17.5 Plasticizer 2 31.21 31.21 31.5 31.5  31.56 Desiccant 1.5 1.5 1.5 1.5  1.5 Thixotropic agent 2 1.75 1.75 1.75 1.75  1.75 Inorganic filler F3 31 31 35.21 34.25  38.25 Hollow microsphere H2 — — 8.0 — — Hollow microspheres H4 — — — 8.96 — Hollow microspheres H5 16 — — — — Hollow microspheres H6 — 16 — — — Hollow microspheres H7 — — — —  1.0 Adhesion promoter 1.0 1.0 1.0 1.0  1.0 Catalyst 1 0.04 0.04 0.04 0.04  0.04 TOTAL 100 100 100 100 100 Test results Tensile strength [MPa] 0.86 0.83 1.31 1.57  1.07 * Elongation at break [%] 129 117 146 166 175 * Density calculated [kg/L] 1.13 1.13 0.97 0.97  0.88 * Density measured fresh 1.24 1.12 0.97 0.97  1.00 * [kg/L] Density measured after 1.24 1.12 0.97 0.97  1.02 * 6 months at RT [kg/L] * a substantial amount of Z-17 continued to run out of the cartridge after expression.

[0210] Production of STP Compositions Z-1 to Z-18

[0211] The silane-functional polymer STP-1, plasticizer, and desiccant were thoroughly mixed for 5 minutes in a vacuum mixer in the parts by weight indicated in Tables 2 to 5. The respective fillers, hollow microspheres, and thixotropic agents were then kneaded in at 60° C. for 15 minutes. With the heating switched off, adhesion promoter, catalyst, and optionally stabilizer were then added and the mixture was processed into a homogeneous paste under reduced pressure for 10 minutes. The paste was then transferred to internally-coated aluminum applicator gun cartridges and, after storage, used further for the test specimens. The exact quantities (in % by weight based on the total composition in each case) of the individual raw materials for the respective experiments are shown in Tables 2 to 5.

[0212] The test results in Tables 2 to 5 show clearly that the compositions according to the invention are superior to the non-inventive examples in respect of high tensile strength, low extrusion force, low thread formation, stability to pumping, while having the same low density.