SEALANT COMPOSITION

Abstract

A one-part room temperature vulcanisable (RTV) silicone composition is provided. The one-part RTV silicone composition comprises a polyorganosiloxane polymer comprising at least two hydrolysable groups per molecule, anhydrous reinforcing filler(s), cross-linker(s), a tin (iv) based condensation catalyst and one or more low molecular weight linear or branched nitrogen containing compounds. The compounds are selected from amidines, guanidines and other alkyl amines and alkyl polyamines. The composition is designed to be storable for at least 6 months at a temperature (T C.) in a range of between 0 C. and 25 C. inclusive.

Claims

1. A one-part condensation curable room temperature vulcanisable (RTV) silicone composition comprising: (a) an organopolysiloxane polymer having at least two hydroxyl or hydrolysable groups per molecule of the formula
X.sub.3-nR.sub.nSi-(Z).sub.d-(O).sub.q(R.sup.1.sub.ySiO.sub.(4-y)/2).sub.z(SiR.sup.1.sub.2-Z).sub.d-SiR.sub.nX.sub.3-n(1) in which each X is independently a hydroxyl group or a hydrolysable group, each R is an alkyl, alkenyl or aryl group, each R.sup.1 is an X group, alkyl group, alkenyl group or aryl group and Z is a divalent organic group; d is 0 or 1, q is 0 or 1, and (d+q)=1; n is 0, 1, 2 or 3, y is 0, 1 or 2, optionally 2, and z is an integer such that the organopolysiloxane polymer has a viscosity of from 30,000 to 150,000 mPa.Math.s at 25 C., optionally of from 40,000 to 140,000 mPa.Math.s at 25 C., in an amount of from 35 to 90% by weight of the composition; (b) one or more essentially anhydrous reinforcing filler(s); (c) one or more cross-linker(s) in the form of a silicon containing compound having at least two, optionally at least three hydrolysable groups per molecule; (d) a tin (iv) based condensation catalyst in an amount of from 0.001 to 0.1% by weight of the composition; and (e) one or more low molecular weight linear or branched nitrogen containing compounds selected from amidines, guanidines and other alkyl amines and alkyl polyamines, in an amount of from 0.1 to 3.5% by weight of the composition.

2. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1, wherein the organopolysiloxane polymer (a) is of the formula structure
X.sub.3-nR.sub.nSi-(Z)-(R.sup.1.sub.ySiO.sub.(4-y)/2).sub.z(SiR.sup.1.sub.2-Z)-SiSiR.sub.nX.sub.3-n wherein n is 0 or 1 and each X is an alkoxy group.

3. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 wherein the reinforcing filler (b) comprises a hydrophobically treated essentially anhydrous fumed silica and/or a precipitated silica having a surface area of at least 50.0 m.sup.2/g measured using the BET method in accordance with ISO 9277:2010.

4. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 wherein the composition and resulting cured material are translucent and/or transparent.

5. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 wherein the tin (iv) condensation catalyst (d) is selected from one or more of tin triflates, dialkyltin compounds, selected from dimethyltin di-2-ethylhexanoate, dimethyltin dilaurate, di-n-butyltin diacetate, di-n-butyltin di-2-ethylhexanoate, dimethyltin dineodecanoate (DMTDN), di-n-butyltin dicaprylate, di-n-butyltin di-2,2-dimethyl octanoate, di-n-butyltin octanoate, di-n-butyltin dilaurate (DBTDL), di-n-butyltin distearate, di-n-butyltin dimaleate, di-n-butyltin dioleate, di-n-octyltin di-2-ethylhexanoate, di-n-octyltin di-2,2-dimethyl octanoate, di-n-octyltin dimaleate, di-n-octyl tin dilaurate, di-n-butyl tin oxide, carbomethoxyphenyl tin trisuberate, tin butyrate, butyltintri-2-ethylhexoate tin naphthenate, isobutyltintriceroate, tin octoate, triethyltin tartrate and di-n-octyl tin oxide.

6. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 wherein component (e) comprises linear or branched organic molecules containing one or more of the groups (1) to (4) depicted below: ##STR00002## wherein each R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 is the same or different and is selected from hydrogen, an alkyl group, a cycloalkyl group, a phenyl group, or an aralkyl group.

7. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 wherein component (e) comprises one of more of guanidine, tetramethyl guanidine, 1,1,3,3-tetramethylguanidine (TMG) having the structure (CH.sub.3).sub.2NCNH(N(CH.sub.3).sub.2), dibutyl amine, ethylene diamine, tri-ethylentertamine and diethylenetriamine.

8. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 capable of being applied as a paste to a joint between two adjacent substrate surfaces where it can be worked, prior to curing, to provide a smooth surfaced mass which will remain in its allotted position until it has cured into an elastomeric body adherent to the adjacent substrate surfaces.

9. The one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1 which is adherable to poly vinyl chloride substrates.

10. A silicone elastomer which is the reaction product obtained by curing the one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1.

11. The silicone elastomer in accordance with claim 10, which is transparent and/or translucent and/or non-staining.

12. A method of making the one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1, comprising mixing all of the ingredients together.

13. A sealant comprising or formed from the one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1, wherein the sealant is suitable for use in the facade, insulated glass, window construction, automotive, solar and construction fields.

14. A sealant comprising or formed from the one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1.

15. A method for filling a space between two substrates so as to create a seal therebetween, comprising: a) providing the one-part room temperature vulcanisable (RTV) silicone composition in accordance with claim 1, and either; b) applying the one-part RTV silicone composition to a first substrate, and bringing a second substrate in contact with the one-part RTV silicone composition that has been applied to the first substrate, or c) filling a space formed by the arrangement of a first substrate and a second substrate with the one-part RTV silicone composition and curing the one-part RTV silicone composition.

16. The method for filling a space between two substrates in accordance with claim 15, wherein the space is filled by introducing the one-part RTV silicone composition by way of extrusion or through a sealant gun and/or wherein one of the substrates is polyvinyl chloride (PVC).

Description

EXAMPLES

[0128] All viscosity measurements were taken at 25 C. unless otherwise indicated. Unless otherwise indicated, all viscosities in the examples were measured using a Modular Compact Rheometer (MCR) 302 rheometer from Anton Paar GmbH of Graz, Austria. Viscosities in the range of 30,000-160,000 mPa.Math.s were measured using a 40 mm diameter cone-plate and a shear rate of 1 s.sup.1; viscosities in the range 2000-30,000 mPa.Math.s were measured with a 50 mm diameter cone-plate and a shear rate of 1 s.sup.1; and viscosities in the range 10-2000 mPa.Math.s were measured with a 75 mm diameter cone-plate and a shear rate of 1 s.sup.1.

[0129] The following ingredients are referred to in the examples: [0130] Polymer A: a tri-methoxy-terminated polydimethylsiloxane polymer with viscosity of 50,000 mPa.Math.s; [0131] Polymer B: a Tri-ethoxy/trimethyl terminated essentially linear polydimethylsiloxane polymer with viscosity of 115,000 mPa.Math.s. The ratio of Tri-ethoxy ends to tri-methyl ends have been determined by NMR and corresponds to 85/15; [0132] Polymer B-1: a Tri-methoxy/trimethyl terminated essentially linear polydimethylsiloxane polymer with viscosity of 123,000 mPa.Math.s. The ratio of Tri-methoxy end groups to tri-methyl end groups were determined by NMR and correspond to 85/15; [0133] Polymer C: Tri-ethoxy terminated, essentially linear polydimethylsiloxane polymer with viscosity of mPa.Math.s; [0134] Polymer D: Tri-methyl terminated, essentially linear polydimethylsiloxane polymer with viscosity of 100 mPa.Math.s [0135] Polymer E: Tri-methyl terminated, essentially linear polydimethylsiloxane polymer with viscosity of 1000 mPa.Math.s
The term essentially in the phrase essentially linear polydimethylsiloxane means that the polymer is in each case linear, in so far as we are aware, but it can't be 100% discounted that minor amounts of branching may have occurred during manufacture. [0136] Aerosil R972 is a hydrophobic fumed silica after treated with dimethyldichlorosilanes from Evonik with a specific surface area of 90-130 m.sup.2/g (supplier data); [0137] Aerosil R974 is a hydrophobic fumed silica after treated with dimethyldichlorosilanes based on a hydrophilic fumed silica with a specific surface area of 150-190 m.sup.2/g from Evonik (supplier data); [0138] MTM is methyl-tri methoxysilane; DBTDL Dibutyltin dilaurate; DBTDN is Dimethyltin dineodecanoate; DBN is 1,5-Diazabicyclo(4.3.0)non-5-ene; DBU is 1,8-Diazabicyclo[5.4.0]undec-7-ene; [0139] TnBT is tetra n-butyl titanate; and HMDZ is Hexamethyldisilazane.

[0140] Comparative compositions were prepared using the compositions depicted in Tables 1a and 1b.

TABLE-US-00001 TABLE 1a Composition of comparative formulations C1 C2 C3 C4 C5 C6 Polymer A 27.228 86.861 87.145 87.432 27.174 27.422 Polymer B 58.994 58.877 59.414 MTM 1.452 2.389 2.397 2.404 1.449 1.463 1,6-bis(trimethoxysilyl)hexane 0.363 0.362 0.366 vinylmethyl-dimethoxysilane 1.452 1.449 1.463 DBTDN 0.326 0.327 0.328 DBTDL 0.073 0.072 0.073 DBU 0.272 0.326 0.327 0.272 0.274 aminopropyl-tri-ethoxysilane 0.182 0.326 0.181 0.183 AerosilR 972 9.076 8.686 9.058 AerosilR 974 8.715 8.743 8.227 HMDZ 0.908 1.086 1.089 1.093 0.906 0.914 TnBT 0.200 0.201

TABLE-US-00002 TABLE 1b Composition of comparative formulations Ingredient C7 C8 C9 C10 C11 C12 C13 Polymer A 27.396 27.522 27.397 27.523 18.348 Polymer B 59.358 59.629 59.362 59.633 68.803 86.754 Polymer C 84.653 MTM 1.461 1.468 1.461 1.468 1.468 1.461 1.693 1,4-bis(trimethoxysilyl) hexane 0.365 0.367 0.365 0.367 0.367 0.365 0.423 vinylmethyl-dimethoxysilane 1.461 1.468 1.461 1.468 1.468 1.461 1.693 AerosilR 974 8.219 8.257 8.219 8.257 8.257 8.219 9.523 HMDZ 0.913 0.459 0.913 0.459 0.459 0.913 1.058 DBTDL 0.078 0.078 0.073 0.073 0.078 0.078 0.09 DBU 0.274 0.275 0.275 0.274 0.317 DBN 0.274 0.275 TnBT 0.201 0.202 0.201 0.202 0.202 0.201 0.233 Aminopropyl-triethoxysilane 0.274 0.275 0.274 0.275 0.275 0.274 0.317

[0141] Comparative examples (C1 to C4) were prepared in a series of initial experiments using a DAC 600.1vac-p Speed Mixer, equipped with a vacuum capability. First the polymer(s) were mixed with the HMDZ and then filler (silica) was added gradually until fully incorporated in the polymer(s). Subsequently the cross-linker(s), adhesion promoter(s) and optional additives are added and mixed into the composition. The catalyst and booster were then added and after further mixing the final composition was degassed to remove volatiles liberated during the process Immediately after compounding the resulting products (sealants) were transferred into moisture tight cartridges. One cartridge was kept at 90 C. and another was maintained at room temperature (20-23 C.).

[0142] Excepting example E10, the remaining examples, including comparatives (C5-C13) were prepared using the same mixing process but it was carried out in a 5 L batch mixer, equipped with mixing blades and vacuum capability. In C5-C13, unless stated otherwise, about 3 kg of material was produced per comparative and this was subsequently transferred to and stored in 330 mL sealant cartridges, which were sealed immediately after introduction to prevent ingress of moisture. Example E10 was made following a different process. Starting again with a double-wall kettle of the 5 L mixer the polymers were first added and then heated to a temperature of about 75 C. Then the trimethoxy silane, DBTDL, TMG and amino-silane were added and the resulting mixture was thoroughly mixed and degassed. The silica was then added in 3 approximately equal portions with mixing in between each addition until complete incorporation. This was followed by a further degassing step. Finally, the HMDZ was added and fully incorporated. The resultant sealant composition was degassed and drummed off.

[0143] Skin over time (SOT) and tack free time (TFT) for compositions C1-C4 are provided in Table 2a after being subjected to different storage conditions.

[0144] The SOT measurement is undertaken by first applying a 1-2 mm thick smear of the composition cast on a polyethylene sheet or Kraft paper. This is a rapid finger test repeated periodically (e.g., every 1-2 minutes) aimed to determine the minimum time needed for a surface skin to appear undertaken at room temperature (20-23 C.) and approximately 50% relative humidity (RH).

[0145] The TFT measurement is also undertaken by first applying a 1-2 mm thick smear of the composition cast on a polyethylene sheet or Kraft paper. A small, clean polyethylene (PE) ribbon is applied after set periods of time e.g., every 1-2 minutes and then is carefully withdrawn. The test is repeated in time on different positions of the smear and the TFT is deemed achieved when the ribbon detaches cleanly (i.e., tack free) from the surface of the smear.

[0146] Compositions were heat aged as a practical means of accelerating the ageing effect at room temperature (20-23 C.). In the majority of cases if a composition can withstanding 6 weeks (wks.) of ageing at 50 C. one can anticipate it will age adequately well at room temperature (20-23 C.) over a period of for 9-12 months. Similarly, 4 wks. storage at 50 C. is roughly equivalent to the effect of ageing at room temperature (20-23 C.) over a period of about 6 months. That said the physical results of samples tested in both ways will not necessarily result in the same physical properties after ageing. Testing on heat aged samples was only carried out after the cartridge holding the composition was cooled for at least 4 hours. The SOT and TFT of samples aged for 6 months at room temperature (RT) prior to curing are also provided.

TABLE-US-00003 TABLE 2 SOT and TFT times (min.) during cure of comparative formulations prepared C1 to C4 C1 C2 C3 C4 SOT-initial 37 30 42 149 TFT-initial 70 58 60 >170 SOT - after 24 h @90 C. 38 34 NT NT TFT - after 24 h @90 C. 51 65 NT NT SOT - after 48 h @90 C. 43 >300 25 NT TFT - after 48 h @90 C. 66 >300 66 NT SOT -after 6 months at RT Cured >90 >100 NT TFT -after 6 months at RT in ctg >90 >100 NT Not all possible tests are performed on each and every formulation. The abbreviation NT stands for not tested. Cured in ctg stands for cured in cartridge, i.e., during storage. In the case of each of C1 to C4 the compositions are non-functional after 6 months. The C1 composition cured in the cartridge and C2 and C3 took too long to provide a TFT to be practically useful.

[0147] Example C4 shows that a tin based catalyst alone does not yield an adequately curing sealant. One notices that accelerated ageing at high temperature does not predict the commercial viability of the sealant, none of the examples being able to withstand 6 months ageing at room temperature (20-23 C.).

[0148] Table 3 shows the cure time of C5 to C13 using accelerated ageing at 50 C. as well as shelf-life (storage stability) measured at 6, 9 and 12 months (1 yr) under laboratory storage conditions.

TABLE-US-00004 TABLE 3 SOT and TFT measurements of comparative examples (minutes) after various periods of ageing as indicated: C5 C6 C7 C8 C9 C10 C11 C12 C13 SOT- (initial) 16 15 9 12 14 13 14 15 10 TFT-(initial) 30 42 23 30 22 21 25 27 14 SOT 2 wk @ 50 C 26 12 11 16 16 13 29 18 11 TFT- 2 wk @ 50 C. 45 37 20 29 32 32 45 39 15 SOT -4 wk @ 50 C. 37 20 17 30 37 50 56 54 28 TFT -4 wk @ 50 C. 64 64 60 < 90 83 58 64 >127 92 41 SOT 6 wk @ 50 C. NT NT >100 NT NT NT 60 < 120 60 < 86 ~56 TFT 6 wk @ 50 C NT NT >190 NT NT NT 150 140 77 SOT 6 m RT 29 80 60 60 NT NT 150 120 80 TFT 6 m RT >123 >180 >180 140 NT NT 210 140 105 SOT 9 m RT NT NT NT NT ~180 ~180 >360 >360 >360 TFT 9 m RT NT NT NT NT ~240 ~240 >360 >360 >360 SOT 1 y RT >195 ~300 >240 ~300 NT NT NT NT NT TFT 1 y RT >300 >300 >240 ~300 NT NT NT NT NT For values in the above Table prefixed with > the composition being tested had a SOT and/or TFT after the period indicated but no further measurements were made. The term in > e.g., >195 in Table 3 means that the value of SOT or TFT was greater than 195 minutes. Similarly, the term 60 < 90 indicates that the SOT or TFT test was undertaken after 60 minutes and 90 minutes and that the SOT or TFT was somewhere between the two.

[0149] It can be seen that none of these features 9 months of storage stability. Although C5 to C10 seems to withstand the accelerated ageing of 4 wks at 50 C., their cure is substantially slower at 6 m of RT storage and ageing impacts the mechanical properties and adhesion.

[0150] Table 4 shows the mechanical properties of the comparative examples C5 to 13.

[0151] The ageing of the compositions described above consisted of storing cartridges of the sealant under the specified time and conditions. After the designated ageing period the composition or the cured product material resulting from cure of the composition were tested within 48 hours of the completion of the required ageing period. The initial properties were determined within 48 hours after mixing.

[0152] Mechanical properties were determined using either H-bar test pieces or dumbbell test pieces as indicated and described below.

[0153] For the H-bar test specimen a sample of the composition having the dimensions 121250 mm was sandwiched between two substrates. The two substrates were both made of glass, both made of aluminium or one of glass and one of aluminium with dimensions 1275 mm as stipulated ISO 8339 Second edition 2005 Jun. 15. Unless otherwise indicated the substrates used for the testing herein were one glass and one aluminum substrate. Such specimens are generally referred to in the industry as H-bars or H-pieces, this notation together with the abbreviation (HP) will be used throughout the examples below. Each specimen is cured for 28 Days at room temperature (20-23 C.) and approximately 50% relative humidity (RH).

[0154] Cured specimen were mechanically tested using a tensile traction test as described in ISO 8339 The tensile strength necessary to break the piece and elongation at break were recorded. The failure was visually observed and the percentage of the surface that corresponded to cohesive failure (CF) was quantified. The break parameters recorded e.g., tensile strength and Elongation at break are expressed in MPa and % respectively.

[0155] Cohesive failure (CF) is observed when a cured material breaks without detaching from a substrate to which it is adhered. Adhesive failure (AF) refers to the situation when the cured material detaches cleanly (i.e., peels off) from a substrate. In some cases, a mixed failure mode may be observed: where there is a mixture of AF and CF. In such a situation the proportions of surface displaying CF (% CF) and AF (% AF) behavior are determined with % CF+% AF=100%. The values listed in Table 4 below refer to the % CF observed.

[0156] For each test in Table 4 the reported values represent arithmetic means of 3 or 4 independent measurements. Samples showing less than 85% CF after a 28-day cure period were deemed to have failed the tensile testing. Cured materials, e.g., sealants were deemed stable if 75% of the tensile strength measured on H-bars is retained after ageing

TABLE-US-00005 TABLE 4 mechanical properties of comparative formulations measured on H-bars. Ageing refers to the sealant C5 C6 C7 C8 C9 C10 C11 C12 C13 Fresh sealant, 28 D cure CF (%) 0 30 100 100 20 30 100 100 100 Tensile Strength (MPa) 0.12 0.22 0.52 0.47 0.21 0.2275 0.55 0.43 0.75 Elongation at Break (%) 25 73 182 126 45.25 43 134 234 163 4 wks Ageing, 28 D cure CF (%) NT NT 0 0 NT NT 100 100 100 Tensile Strength (MPa) NT NT 0.05 0.05 NT NT 0.39 0.32 0.41 Elongation at Break (%) NT NT 8.5 9 NT NT 150 178 700

[0157] None of the comparative cured materials made from comparatives C5 to C13 in Table 4 have good mechanical properties. C5, C6,C9 and C10 show inadequate initial adhesion, whereas C7 and C8 show a complete loss in adhesion upon ageing. It was found that in the case of comparatives C11, C12 and C13 adequate adhesion was retained but they suffered a severe loss of tensile strength, i.e., results were less than 75% of the initial value which is deemed inadequate.

[0158] Table 5 shows the mechanical properties of selected comparative formulation measured using dumbbell test pieces. 2 mm thick sheets were prepared for each sample and were then cured at room temperature (20-23 C.) and about 50% relative humidity for 7 days. Standard dumbbell shaped test pieces were then cut out of the sheets either immediately or after a suitable period of ageing and the mechanical properties of these specimens tested following ASTM D 412 -06. Shore A was tested as described in ASTM D 2240. The reported values represent average values of 4 or 5 independent measurements. Sealants were deemed stable if 75% of the tensile strength and hardness (Shore A) were retained upon ageing.

TABLE-US-00006 TABLE 5 Further Mechanical properties of C11, C12 and C13 using dumbbell Test pieces C11 C12 C13 Shore A (initial) 14.3 12.3 24.7 Tensile Strength (MPa) (initial) 1.54 1.7 1.72 Max. Elongation (%) (initial) 429 555 340 Modulus @ 100% elongation (MPa) (initial) 0.45 0.38 0.62 Shore A (after 4 wks. @ 50 C.) 6 6 16.7 Tensile Strength (MPa) (after 4 wks. @ 0.87 0.92 1.68 50 C.) Max. Elongation (%) (after 4 wks. @ 440 527 416 50 C.) Modulus @ 100% elongation (MPa) (after 0.32 0.32 0.51 4 wks. @ 50 C.)

[0159] It can be seen that C11, C12 and C13 all exhibit a severe loss in hardness and tensile strength.

TABLE-US-00007 TABLE 5b provides a qualitative summary of the comparative formulations. C5 C6 C7 C8 C9 C10 C11 C12 C13 cure time retained OK OK OK OK almost almost No No OK 4 wks 50 C. cure time retained almost almost almost almost NT NT No No No 6 months RT cure time retained NT NT NT NT NT NT NT NT NT 9 months RT cure time retained NT NT NT NT NT NT NT NT NT 1 yr RT Mechanical Fails Fails OK OK Fails Fails OK OK OK properties @ start retained NT NT No No NT NT No No No mechanical properties 4 wks 50 C.

[0160] Table 6 shows the composition of inventive formulations, table 7 shows SOT and TFT time, whereas table 8 and 9 show the mechanical properties measured on dumbbells respectively.

[0161] Inventive examples E1, E2, E3, E4, containing DBA or TMG boosters are compositional analogues of C7, C8, C9,C10 the only difference being the inclusion of the respective booster molecule. One notices that the choice of appropriate booster affords sealants of adequate application properties.

TABLE-US-00008 TABLE 6 Composition of inventive formulations Ingredient E1 E2 E3 E4 E5 E6 Polymer A 27.422 27.397 27.397 27.523 Polymer B 59.414 59.362 59.362 59.633 86.754 Polymer C 84.653 MTM 1.463 1.461 1.461 1.468 1.461 1.693 1,6-bis(trimethoxysilyl)hexane 0.366 0.365 0.365 0.367 0.365 0.423 vinylmethyl-dimethoxysilane 1.463 1.461 1.461 1.468 1.461 1.693 AerosilR 974 8.227 8.219 8.219 8.257 8.219 9.523 HMDZ 0.914 0.913 0.913 0.459 0.913 1.058 DBTDL 0.073 0.073 0.073 0.073 0.078 0.09 Dibutylamine 0.274 0.274 Tetramethylguanidine 0.274 0.275 0.274 0.317 TnBT 0.201 0.201 0.201 0.202 0.201 0.233 Aminopropyl-triethoxysilane 0.183 0.274 0.274 0.275 0.274 0.317

TABLE-US-00009 TABLE 7 SOT and TFT values (min) of inventive formulations after various periods of ageing E1 E2 E3 E4 E5 E6 SOT (initial) 43 35 19 16 20 14 TFT (initial) 110 160 40 33 38 30 SOT (after 2 wks. @ 50 C.) 19 22 12 12 10 18 TFT (after 2 wks. @ 50 C.) 65 68 18 18 18 27 SOT (after 4 wks. @ 50 C.) 28 26 16 16 13 15 TFT (after 4 wks. @ 50 C.) 55 54 21 19 23 20 SOT (after 6 months @ RT) NT <100 20 16 NT NT TFT (after 6 months @ RT) NT <100 30 25 NT NT SOT (after 9 months @ RT) NT NT 15 17 13 10 TFT (after 9 months @ RT) NT NT 30 30 23 18 SOT (after 1 year @ RT) <100 <100 20 23 9-15 NT TFT 1 (after 1 year @ RT) <100 <100 24 25 27-45 NT

[0162] One notices than all materials have an acceptable cure time after both 9 months and 1 year of room temperature (RT, 20-23 C.) storage.

TABLE-US-00010 TABLE 8 Mechanical properties of selected inventive formulations measured on H-bars after various periods of ageing. Each test piece being cured for 28 days before testing. Ageing refers to the sealant composition stored in moisture tight cartridge at 50 C. E2 E3 E4 E5 E6 % CF (initial) 95% 90% 95% 100% 100% Tensile Strength (MPa) 0.38 0.37 0.45 0.45 0.73 (initial) Elongation max, % (initial) 93 85 112 188 134 % CF (after 2 wks Ageing) NT 100 100 100 100 Tensile Strength (MPa) NT 0.37 0.35 0.39 0.75 (after 2 wks Ageing) Elongation max, % (after 2 NT 85 86 152 131 wks Ageing) % CF (after 4 wks Ageing) NT 100 100 100 100 Tensile Strength (MPa) NT 0.48 0.35 0.46 0.63 (after 4 wks Ageing) Elongation max, % (after 4 NT 157 87 188 104 wks Ageing) % CF (after 1 year Ageing) NT 100% 100% NT NT Tensile Strength (MPa) NT 0.48 0.51 NT NT (after 1 year Ageing) Elongation max, % (after 1 NT 152 149 NT NT year Ageing) Elongation max, % means elongation at break.

TABLE-US-00011 TABLE 9 Mechanical properties of E5 and E6 formulations measured on dumbbells E5 E6 Shore A (initial) 10.7 21 Tensile Strength (MPa) (initial) 1.65 1.38 Elongation at break % (initial) 531 455 Modulus at 100% elongation (initial) 0.37 0.38 Shore A (after 2 weeks (wks.) @ 50 C.) 12.3 23.7 Tensile Strength (MPa) (after 2 wks. @ 50 C.) 1.64 2.13 Elongation at break % (after 2 wks. @ 50 C.) 472 339 Modulus at 100% elongation (after 2 wks. @ 50 C.) 0.41 0.71 Shore A (after 4 wks. @ 50 C.) 12 24 Tensile Strength (MPa) (after 4 wks. @ 50 C.) 1.47 1.86 Elongation at break % (after 4 wks. @ 50 C.) 468 339 Modulus at 100% elongation (after 4 wks. @ 50 C.) 0.39 0.64

[0163] It can be seen that mechanical properties as well as adhesion (determined on H-bars) are well retained. Same holds for hardness (shore A) and tensile strength measured on dumbbells.

TABLE-US-00012 TABLE 10 shows a qualitative summary of the properties of E1 to E6 E1 E2 E3 E4 E5 E6 cure time retained 4 wks 50 C. OK OK OK OK OK OK cure time retained 6 months RT NT OK OK OK NT NT cure time retained 9 months RT NT NT OK OK OK OK cure time retained 1 yr RT OK OK OK NT NT NT mechanicals @ start OK OK OK OK OK OK retained mechanical properties 4 wks 50 C. NT NT OK OK OK OK

[0164] It can be seen that E1 and E2 were stable for 1 year at room temperature and they both satisfied the accelerated ageing at 50 C. for 4 weeks. E3 and E4 retain their mechanical properties upon 4 weeks of accelerated ageing at 50 C. E5 and E6 were stable for 1 year at room temperature and retained their mechanical properties after 4 weeks of accelerated ageing at 50 C.

[0165] Further examples E7 to 10 were prepared. Examples 9 and 10 show that this work with extended sealant compositions. Compositions are depicted in Table 11 and results are shown in Tables 12 and 13 below.

[0166] Table 11 shows the composition (all values in wt. %) of Examples 7, 8, 9 and 10 which were used to analyse the adhesiveness of compositions as disclosed herein.

TABLE-US-00013 E7 E8 E9 E10 Polymer B 86.519 86.283 58.50 Polymer B-1 56.42 Aerosil R 974 8.196 8.174 9.00 9.10 MTM 1.457 1.453 1.44 2.00 HMDZ 0.911 0.908 0.90 1.00 DBTDL 0.077 0.077 0.08 0.08 TMG 0.273 0.272 0.27 0.30 Polymer D 27.00 Polymer E 30.20 aminoethyl aminopropyl trimethoxy 0.546 0.90 silane (distilled) aminoethyl aminopropyl trimethoxy 0.817 0.81 silane (technical grade, 20% impurities) 1,6-bis(trimethoxysilyl)hexane 0.364 0.363 .36 vinylmethyl-dimethoxysilane 1.457 1.453 1.44 TnBT 0.200 0.200 0.20

TABLE-US-00014 TABLE 12 SOT and TFT results for Examples 7, 8, 9 and 10(E7, E8, E9 and E10) E7 E8 E9 E10 SOT (initial) 15 5-15 24 8 TFT (initial) 60-80 65 75 29 SOT (after 4 wks. @ 50 C.) 10 24 15 18 TFT(after 4 wks. @ 50 C.) 55-75 47 22 41 SOT (after 6 wks. @ 50 C.) 51 60 20 19 TFT(after 6 wks. @ 50 C.) 87 140 > 170 120 45-55

[0167] It can be seen form Table 12 that E7, E8, E9 and E10 all satisfied the accelerated ageing of 6 weeks at 50 C. E7, E8, E9 and E10 were tested to determine their adhesion to polyvinyl chloride (PVC). White PVC substrates having dimensions of 15 by 7.5 cm were prepared by cleaning with isopropanol 5 to 10 minutes before extruding a finger of silicone along the longer side of the substrate Immediately upon extrusion, the finger was gently pressed with a spatula to form a test specimen of approx. 1 cm width and 5-8 mm thickness. These samples were stored at room temperature and 50% relative humidity (RH). At regular intervals an undercut close to the PVC substrate was done in a direction perpendicular to the sealant finger. The resulting loose end produced was then manually pulled for a couple of cm. The results are an average of two tests. The sealant was deemed to adhere to PVC if the pulling on the finger results in the break within the sealant without detachment from the substrate for at least 50% of the initially covered PVC surface.

TABLE-US-00015 TABLE 13 Adhesion to PVC E7-E10 Finger peel cured 7 Days (initial) 100% CF Finger peel cured 14 Days (initial) 100% CF Finger peel cured 21 Days (initial) 100% CF Finger peel cured 28 Days (initial) 100% CF Finger peel cured 7 Days (after 4 wks. ageing at 50 C.) 100% CF Finger peel cured 14 Days (after 4 wks. ageing at 50 C.) 100% CF Finger peel cured 21 Days (after 4 wks. ageing at 50 C.) 100% CF Finger peel cured 28 Days (after 4 wks. ageing at 50 C.) 100% CF

[0168] In each instance E7 to E10 all resulted in 100% cohesive failure, together with commercially exploitable stability.