INFLATABLE SAFETY DEVICES

Abstract

This disclosure describes inflatable articles such as airbags for inflatable safety devices for a vehicle passenger-protecting system, a process for manufacturing said inflatable articles, hydrosilylation curable silicone elastomer compositions and their uses in assembling said inflatable safety devices. The composition used comprised an organopolysiloxane based additive which comprises at least one, alternatively at least two Si—H groups per molecule and at least one, alternatively at least two functional groups per molecule, selected from anhydride groups and epoxy groups.

Claims

1. An inflatable article comprising: a first fabric sheet and a second fabric sheet superimposed thereon; and a cured silicone adhesive, forming a non-sewn seam-bond between the first and second fabric sheets such that a bag-like structure is created; wherein the non-sewn seam-bond has a peak load/width of at least 3.5 kN/m; and wherein the cured silicone adhesive is the elastomeric product of a curable silicone elastomer composition comprising: (A) one or more organopolysiloxanes containing at least 2 alkenyl groups per molecule and having a viscosity in a range of 1,000 to 500,000 mPa.Math.s at 25° C.; (B) a curing agent comprising (B)(i) an organic peroxide radical initiator; or (B)(ii) a hydrosilylation cure catalyst package comprising a hydrosilylation catalyst and an organosilicon compound having at least 2, optionally at least 3 Si—H groups per molecule; (C) at least one reinforcing filler and optionally one or more non-reinforcing fillers; and (D) one or more organopolysiloxane based additives which comprise at least one, optionally at least two Si—H groups per molecule and which comprises at least one, optionally at least two functional groups per molecule, selected from anhydride groups and epoxy groups.

2. The inflatable article in accordance with claim 1, wherein component (D) of the curable silicone elastomer composition comprises one or more organopolysiloxanes of the following formula
D(Z).sub.d—(O).sub.e—[Y]—(SiR.sup.3.sub.2—Z).sub.dD in which each D group is a cyclic siloxane of the structure
[(O—Si(−)R.sup.3)(OSiR.sup.3H).sub.m(OSiR.sup.3X).sub.a] wherein each R.sup.3 group is an alkyl group containing from 1 to 6 carbons and each X is a group containing an anhydride or epoxide functionality in which m is an integer of at least 1 and a is an integer of at least 1; and [Y] is a linear siloxane group of the structure [SiPhR.sup.3O]n, (SiR.sup.3.sub.2O).sub.n or [SiPh.sub.2O].sub.n; wherein Ph is a phenyl group, Z is an alkylene group having from 2 to 10, optionally 2 to 6 carbons, and n is an integer of from 2 to 20 with d=e=0 or 1 and d+e=1 and [Y] is (SiR.sup.3.sub.2O).sub.n when d=1.

3. The inflatable article in accordance with claim 2, wherein component (D) is or comprises a compound selected from one or more of the following: a compound wherein [Y] is a polydimethylsiloxane chain, d is 1, e is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises epoxy functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises anhydride functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises epoxy functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 1, a is 2 and the value of n is an average between 4 and 10 and X comprises epoxy functionality.

4. The inflatable article in accordance with claim 1, with the curable silicone elastomer composition additionally comprising a zirconate and/or a titanate.

5. The inflatable article in accordance with claim 1, further defined as an airbag.

6. The inflatable article in accordance with claim 5, wherein the airbag is an uncoated airbag.

7. A process for making an inflatable article, the process comprising: (i) applying a first bead of a curable silicone elastomer composition around the periphery of a first fabric sheet, the curable silicone elastomer composition comprising: (A) one or more organopolysiloxanes containing at least 2 alkenyl groups per molecule and having a viscosity in a range of 1,000 to 500,000 mPa.Math.s at 25° C.; (B) a curing agent comprising (B)(i) an organic peroxide radical initiator; or (B)(ii) a hydrosilylation cure catalyst package comprising a hydrosilylation catalyst and an organosilicon compound having at least 2, optionally least 3 Si—H groups per molecule; (C) at least one reinforcing filler and optionally one or more non-reinforcing fillers; and (D) one or more organopolysiloxane based additives which comprise at least one, optionally at least two Si—H groups per molecule and which comprise at least one, optionally at least two functional groups per molecule, selected from anhydride groups and epoxy groups; (ii) contacting the first bead of the curable silicone elastomer composition with a surface of a second fabric sheet; and (iii) forming a non-sewn seam comprising a cured silicone elastomeric product of the curable silicone elastomer composition thereby adhering the first fabric sheet to the second fabric sheet through a non-sewn seam-bond; wherein the non-sewn seam-bond has a peak load/width of at least 3.5 kN/m.

8. A process for making an inflatable article, the process comprising: (i) applying a first bead of a curable silicone elastomer composition around the periphery of a first fabric sheet, the curable silicone elastomer composition comprising: (A) one or more organopolysiloxanes containing at least 2 alkenyl groups per molecule and having a viscosity in a range of 1,000 to 500,000 mPa.Math.s at 25° C.; (B) a curing agent comprising (B)(i) an organic peroxide radical initiator; or (B)(ii) a hydrosilylation cure catalyst package comprising a hydrosilylation catalyst and an organosilicon compound having at least 2, optionally at least 3 Si—H groups per molecule; (C) at least one reinforcing filler and optionally one or more non-reinforcing fillers; and (D) one or more organopolysiloxane based additives which comprise at least one, optionally at least two Si—H groups per molecule and which comprise at least one, optionally at least two functional groups per molecule, selected from anhydride groups and epoxy groups; (ii) applying a second bead of the curable silicone elastomer composition around the periphery of a second fabric sheet; (iii) contacting a first exposed surface of the first bead and a second exposed surface of the second bead to form one bead; and (iv) forming a non-sewn seam comprising a cured silicone elastomeric product of the curable silicone elastomer composition thereby adhering the first fabric sheet to the second fabric sheet through a non-sewn seam-bond; wherein the non-sewn seam-bond has a peak load/width of at least 3.5 kN/m.

9. The process for making an inflatable article in accordance with claim 7, wherein component (D) of the curable silicone elastomer composition comprises one or more organopolysiloxanes having the structure
D(Z).sub.d—(O).sub.e—[Y]—(SiR.sup.3.sub.2—Z).sub.dD in which each D group is a cyclic siloxane of the structure
[(O—Si(−)R.sup.3)(OSiR.sup.3H).sub.m(OSiR.sup.3X).sub.a] wherein each R.sup.3 group is an alkyl group containing from 1 to 6 carbons and each X is a group containing an anhydride or epoxide functionality in which m is an integer of at least 1 and a is an integer of at least 1; and [Y] is a linear siloxane group of the structure [SiPhR.sup.3O]n, (SiR.sup.3.sub.2O).sub.n or [SiPh.sub.2O].sub.n; wherein Ph is a phenyl group, Z is an alkylene group having from 2 to 10, optionally 2 to 6 carbons, and n is an integer of from 2 to 20 with d=e=0 or 1 and d+e=1 and [Y] is (SiR.sup.3.sub.2O).sub.n when d=1.

10. The process in accordance with claim 9, wherein component (D) is or comprises a compound selected from one or more of the following: a compound wherein [Y] is a polydimethylsiloxane chain, d is 1, e is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises epoxy functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises anhydride functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises epoxy functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 1, a is 2 and the value of n is an average between 4 and 10 and X comprises epoxy functionality.

11. The process in accordance with claim 7, wherein the curable silicone elastomer composition additionally comprises a zirconate and/or a titanate.

12. The process in accordance with claim 7, wherein the inflatable article is an airbag.

13. The process in accordance with claim 7, wherein the fabric sheets are activated prior to application of the curable silicone elastomer composition by plasma, corona and/or UV-C.

14. (canceled)

15. (canceled)

16. (canceled)

17. (canceled)

18. The process for making an inflatable article in accordance with claim 8, wherein component (D) of the curable silicone elastomer composition comprises one or more organopolysiloxanes having the structure
D(Z).sub.d—(O).sub.e—[Y]—(SiR.sup.3.sub.2—Z).sub.dD in which each D group is a cyclic siloxane of the structure
[(O—Si(−)R.sup.3)(OSiR.sup.3H).sub.m(OSiR.sup.3X).sub.a] wherein each R.sup.3 group is an alkyl group containing from 1 to 6 carbons and each X is a group containing an anhydride or epoxide functionality in which m is an integer of at least 1 and a is an integer of at least 1; and [Y] is a linear siloxane group of the structure [SiPhR.sup.3O].sub.n, (SiR.sup.3.sub.2O).sub.n or [SiPh.sub.2O].sub.n; wherein Ph is a phenyl group, Z is an alkylene group having from 2 to 10, optionally 2 to 6 carbons, and n is an integer of from 2 to 20 with d=e=0 or 1 and d+e=1 and [Y] is (SiR.sup.3.sub.2O).sub.n when d=1.

19. The process in accordance with claim 18, wherein component (D) is or comprises a compound selected from one or more of the following: a compound wherein [Y] is a polydimethylsiloxane chain, d is 1, e is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises epoxy functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises anhydride functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 4 and 10 and X comprises epoxy functionality; a compound wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 1, a is 2 and the value of n is an average between 4 and 10 and X comprises epoxy functionality.

20. The process in accordance with claim 8, wherein the curable silicone elastomer composition additionally comprises a zirconate and/or a titanate.

21. The process in accordance with claim 8, wherein the inflatable article is an airbag.

22. The process in accordance with claim 8, wherein the fabric sheets are activated prior to application of the curable silicone elastomer composition by plasma, corona and/or UV-C.

23. A seam sealant for an inflatable article, the seam sealant comprising or formed from the curable silicone elastomer composition according to claim 1.

Description

EXAMPLES

[0134] In the following examples all viscosities were measured using a Brookfield® rotational viscometer using Spindle (LV-4) and adapting the speed according to the polymer viscosity. All viscosity measurements were taken at 25° C. unless otherwise indicated.

TABLE-US-00001 TABLE 1a composition used for examples with varying Additives as indicated below Control Control Part A Part A Part B Ex. 1-5 Ingredient (wt. %) (wt. %) (wt. %) Masterbatch 1 50.30 50.87 50.30 dimethylvinyl-terminated Dimethyl siloxane gum 1.75 1.70 1.75 having a Williams plasticity of 156 mm/100 (ASTM D- 926-08)(Gum 1) Calcium carbonate, fatty acid treated 17.55 17.06 17.55 Quartz (average particle size 5 μm) 5.84 5.68 5.84 Dimethyl hydroxy terminated Dimethyl siloxane 1.75 1.70 1.75 viscosity of 42 mPa .Math. s Dimethylvinyl terminated Dimethyl siloxane, viscosity 12.78 9.50 12.78 of about 57,000 mPa .Math. s (Polymer 1) Karstedt's (Pt) catalyst in vinyl polymer Dimethyl 1.69 — 1.69 siloxane, dimethylvinylsiloxy-terminated (catalyst 1) Ethynyl cyclohexanol (ETCH) in — 1.26 — Dimethyl, methylvinyl siloxane, dimethylvinylsiloxy- terminated (inhibitor 1) Dimethyl, methylvinyl siloxane, dimethylvinylsiloxy- 7.73 3.15 7.73 terminated viscosity of about 340 mPa .Math. s Dimethyl, methylhydrogen siloxane, trimethylsiloxy- — 0.66 — terminated viscosity of about 12-13 mPa .Math. s Dimethyl siloxane, hydrogen-terminated viscosity of — 5.04 — about 10 mPa .Math. s 50 wt % zirconium (IV) acetylacetonate in 50 wt % vinyl 0.60 terminated polydimethylsiloxane

[0135] Masterbatch 1 comprises 68.7% of polymer 1 and 31.3% treated silica.

TABLE-US-00002 TABLE 1b Compositions of part B for Examples 1 to 5 in wt. % of the part B composition Pt. B Pt. B Pt. B Pt. B Pt. B Ingredient Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Masterbatch 1 51.42 50.33 49.81 49.30 50.87 Gum. 1 1.72 1.68 1.67 1.65 1.70 Calcium carbonate, fatty acid treated 17.25 16.88 16.71 16.54 17.06 Quartz (average particle size 5 μm) 5.74 5.62 5.56 5.51 5.68 Dimethyl hydroxy terminated 1.72 1.68 1.67 1.65 1.7 Dimethyl siloxane viscosity of 42 mPa .Math. s Polymer 1 9.60 9.40 9.30 9.20 9.5 Inhibitor 1 1.27 1.24 1.23 1.22 1.26 Dimethyl, methylvinyl siloxane, 3.18 3.12 3.08 3.05 3.15 dimethylvinylsiloxy-terminated viscosity of about 340 mPa .Math. s Dimethyl, methylhydrogen siloxane, 0.66 0.65 0.64 0.64 0.66 trimethylsiloxy-terminated viscosity of about 12-13 mPa .Math. s Dimethyl siloxane, hydrogen- 5.10 4.99 4.94 4.89 5.04 terminated viscosity of about 10 mPa .Math. s Additive 1 2.34 4.40 5.39 6.37 3.38

[0136] Additive 1 indicated in Table 1b above was a mixture of component (D) structures prepared following the process described in U.S. Pat. No. 7,429,636, comprising a majority of molecules (approximately e.g. 57.5 to 62%) having a structure wherein [Y] is a polydimethylsiloxane chain, d is 1, e is zero, m is 2, a is 1, the number of silicons in the linear chain (n+2 in the following structure) is an average about 7 and each cyclic siloxane is an eight membered ring, and it is to be understood that the X group can replace any of the Si—H groups originally positioned in the ring of each cyclic siloxane so the main ingredient of the mixture maybe but is not necessarily the following structure:—

##STR00006##

The rest being a mixture of analogous molecules in which cyclic siloxanes D in the structure were 10 membered rings (approximately 35 to 40%) and the remainder (approximately >0-5%) were where the cyclic siloxanes D in the structure were 12 membered rings. The total amount adding up to 100%

[0137] Physical Properties of Cured Slabs

The formulation specified in the adhesive composition section was used to prepare slabs for measuring physical properties. The respective Part A and part B for compositions as depicted in Table 1 above mixed in a 1:1 weight ratio using a speedmixer and slabs of each sample were prepared and then cured at 150° C. for 5 minutes. The physical properties were then determined as depicted in table 2 below. Elongation and Modulus results cured test pieces (ASTM D412-98A) using DIN S2 die and Shore A hardness was determined in accordance with (ASTM D2240-97). Tear Strength was measured in accordance with ASTM D264.

TABLE-US-00003 TABLE 2 Physical Properties of Control and Ex. 1 to 4 Modulus at 100% Tear Elongation elongation Strength Shore A (%) (MPa) (kN/m) hardness Control 1650 0.23 26 16 Ex. 1 851 0.72 29 34 Ex. 2 714 0.92 26 39 Ex. 3 723 0.85 26 36 Ex. 4 782 0.79 24 37

[0138] Laminates of fabric sheets were prepared using the composition as herein before described including the additives discussed above with a view to assessing the Peak adhesion strength with tearing by peeling the laminate apart at one hundred eighty degrees. As well as the peak adhesion strength, an estimation of the percent cohesive failure is reported which was determined by examining the freshly exposed surface at the completion of the test and estimating the percent cohesive failure. The methodology used was based on ASTM D 413-98 with the following differences machine rate, sample width and sample thickness.

[0139] The fabric was cut along the weft direction (˜12 in) and then in the warp direction (˜16 in) to provide substrate sheets (dimensions 12 in (30.48 cm)×16 in (40.64 cm)). All substrates used were pre-dried at 150° C. for one minute in an oven. The fabric was then removed and placed on a workbench. A chase mold was aligned so that it was positioned straight across the fabric in the weft direction (chase used in this study had a 1.16 mm depth [leads to ˜1 mm thick adhesive line and additionally of 0.65 mm depth [leads to ˜0.5 mm thick adhesive line], and 1.68 mm depth [leads to ˜1.5 mm thick adhesive line]; all internal dimensions are 10 mm x 10 in). The part A and part B compositions were mixed in a 1:1 weight ratio in a speedmixer. A plastic spatula was used to fill the chase with the adhesive. The chase was removed, and a second piece of the respective substrate was placed on top of the sample bead. A Styrofoam roller was then used to gently wet-out the bead. The sample was then cured in the oven at 150° C. for 5 minutes.

[0140] As will be seen below some substrate samples were plasma treated before use. Plasma treatment took place after the substrate sheets had been oven treated. For plasma treated samples, a mark was made on the fabric at the center of the plasma treating line; albeit the marks were not made where the adhesive was going to be applied. The bottom piece of fabric was plasma treated using an FG3001 plasma generator from Plasmatreat; speed set to 125 mm/s. The robot coordinates were set with x=82.24 mm, y=13.76 mm, z=117 mm; these coordinates lead to a 7 mm gap from plasma treating head to fabric). After treatment the samples were applied following the process above. The second substrate sheet was plasma treated and applied with the plasma treated surface toward the sealant bead. Samples were then cured as described above.

[0141] Samples were allowed to sit at room temperature for about 20 hours until analysis was performed. Four samples were cut from each specimen, which consisted of a 10 in seam. The outer 1 in (2.54 cm) of specimen was discarded and four 2 in (5.08 cm) samples were cut. The length of the fabric was then cut to approximately 6 in (15.24 cm) for each sample. The thickness of each sample was measured. This was done by subtracting the width of two pieces of fabric from the width of the overall sample construction.

[0142] Peak adhesion strength with tearing by peeling the laminate apart at one hundred eighty degrees as well as the peak adhesion strength, an estimation of the percent cohesive failure is reported which was determined by examining the freshly exposed surface at the completion of the test and estimating the percent cohesive failure. These were undertaken shortly after cure as discussed above.

[0143] In the case of Peak Load/Width samples were tested using an MTS Alliance RF/100 tensile tester. The adhesion specimen was placed in the sample holder crosshead speed was set to 8 in/min (200 mm/min) and the Peak Load/Width was determined. Results provided in the Tables below were an average of four data points.

[0144] In the case of the cohesive failure measurement this was achieved by analyzing samples pulled Peak Load/Width for percent cohesive failure. A template that contained a 2×10 grid (4 mm×4 mm squares) was placed at the center of the pulled seam, neglecting approximately 5 mm on each side and 2 mm on the top and bottom of the seam. Each square represents a 5% area. The percent cohesive failure was determined for each sample, and then the average was taken of each of the four replicates. Seam thickness was determined using a digital caliper. First, the entire seam thickness was measured. The thickness of the fabric substrate was subtracted from the entire seam thickness to give the thickness of the adhesive layer for which values are given in the following Tables.

[0145] The results for Polyester. 470 DTEX substrates are depicted in Tables 3a.

TABLE-US-00004 TABLE 3a Polyester. 470 DTEX substrate adhesion results Peak Mode of Cure Cure Seam Load/ failure Temp Time thickness Width (% cohesive Treatment (° C.) (min) (mm) (kN/m) failure) Control Plasma 150 5 1.0 0.3 0 Ex. 1 Plasma 150 5 0.9 4.7 25 Ex. 2 Plasma 150 5 0.5 3.0 8 Ex. 2 Plasma 150 5 1.0 4.6 48 Ex. 3 Plasma 150 5 0.5 2.7 10 Ex. 3 Plasma 150 5 1.0 4.2 39 Ex. 4 Plasma 150 5 0.5 2.3 6 Ex. 4 Plasma 150 5 1.0 3.8 60

[0146] It will be appreciated that the control test with no additive or zirconate present achieved no adhesion whilst the other examples in Table 3 achieved adhesion and a Peak Load/Width in accordance with the disclosure herein were obtained for compositions with a seam thickness of at least 0.9 mm. It was also noted results with a seam thickness of at least 0.9 mm gave improved % cohesive failure results.

TABLE-US-00005 TABLE 3b Polyester. 470 DTEX substrate adhesion results for Ex. 5 Mode of Cure Cure Seam Peak failure Temp Time thickness Load/Width (% cohesive Treatment (° C.) (min) (mm) (kN/m) failure) Plasma room temp 24 h 0.9 0.6 0 Plasma 150 5 0.5 3.9 18 Plasma 150 5 1.5 7.3 95 Plasma 150 5 1.0 5.8 72 Plasma 150 1 1.0 2.9 18 Plasma 150 3 1.0 4.8 83 Plasma 150 5 0.9 6.2 84 Plasma 150 10 1.0 5.7 96 Plasma 150 20 1.0 5.3 89 Plasma 180 1 0.9 2.6 9 Plasma 180 2 0.9 4.2 79 Plasma 180 5 1.0 6.1 70 Plasma 190 1 1.0 2.6 10 Plasma 190 2 0.9 4.7 83

[0147] It was found that adhesion was not achieved when cured at room temperature. Whilst, a seam thickness of 0.5 mm leads to an acceptable Peak Load/Width although there was more adhesive failure than cohesive failure. The latter was improved by having a seam thickness of 1 mm when cured at a temperature of 150° C. It was also found that undertaking cure for at least 3 mins, typically 5 mins gave good results. Adhesion is obtained on plasma treated fabric when sample is cured for 5 min at 150° C. or 180° C.

[0148] Similar results were achieved on a nylon 66 substrate as can be seen in Table 4a below as were obtained in Table 3a on a polyester substrate:

TABLE-US-00006 TABLE 4a Nylon 66. substrate adhesion results Peak Mode of Cure Cure Seam Load/ failure Temp Time thickness Width (% cohesive Treatment (° C.) (min) (mm) (kN/m) failure) Control Plasma 150 5 1.0 0.3  0 Ex. 1 None 150 5 0.5 1.0  0 Ex. 1 Plasma 150 5 0.5 3.5 TFCF Ex. 1 Plasma 150 5 1.0 5.7 34 Ex. 2 Plasma 150 5 0.5 3.3 60 Ex. 2 Plasma 150 5 1.0 5.3 78 Ex. 3 Plasma 150 5 0.5 2.9 40 Ex. 3 Plasma 150 5 1.0 4.3 79 Ex. 4 Plasma 150 5 0.5 2.9 44 Ex. 4 Plasma 150 5 1.0 4.2 79 TFCF = thin film cohesive failure

[0149] As previously indicated the control sample which does not contain any additive (D) does not adhere. It is preferred for the substrate to be activated before use e.g. by plasma activation. It was found that a much better cohesive failure occurred with seam seals of at least 0.9 mm, especially when cured at a temperature of greater than 120° C., especially at around 150° C. additive when cured for at least 3 minutes, preferably 5 minutes or more. As in the case above the tests depicted in Table 3b were repeated for a nylon substrate using the formulation depicted as Ex. 5 in Table 1b. The results are depicted in Table 4b below.

TABLE-US-00007 TABLE 4b Nylon 66. substrate adhesion results for Ex. 5 compositions (+control) Mode of Cure Cure Seam Peak failure Temp Time thickness Load/Width (% cohesive Treatment (° C.) (min) (mm) (kN/m) failure) (Control) 150 5 1.0 0.3 0 Plasma Plasma room temp 24 h 1.0 0.5 0 Plasma 150 5 0.5 3.8 29 Plasma 150 5 1.4 6.5 97 Plasma 150 5 0.9 5.0 68 Plasma 150 5 0.9 5.0 46 Plasma 150 1 1.0 2.3 3 Plasma 150 3 1.0 4.1 65 Plasma 150 10 1.0 5.4 100 Plasma 150 20 1.0 5.3 97 Plasma 180 1 0.9 2.4 5 Plasma 180 2 0.9 4.2 89 Plasma 180 5 1.1 5.7 91 Plasma 190 1 0.9 3.1 26 Plasma 190 2 1.0 4.8 88 Plasma 150 5 1.0 4.3 79 Plasma 150 5 0.5 2.9 44 Plasma 150 5 1.0 4.2 79 TFCF = thin film cohesive failure

[0150] Adhesion was not achieved when cured at room temperature. A seam thickness of 0.5 mm rarely provided a sufficient result and it was seen that seals of at least 0.9 mm thickness generally leads to more adhesive failure than cohesive failure and excellent peak Load/Width results. Likewise, it was found that short cure times of less than 3 minutes generally didn't give good enough peak Load/Width results. For example, good results were achieved for adhesion on plasma treated fabric when sample is cured 5 min at temperatures between 150° C. and 190° C.

[0151] The above test for Peak Load/Width (kN/m) and cohesive failure were repeated using the formulation of Ex. 5 but by replacing Additive 1 with an anhydride additive (Additive 2) which was a mixture of component (D) structures prepared following the process described in PCT/US19/064350, comprising a majority of molecules (approximately e.g. 51 to 55%) having a structure wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 6 and 7, each X is an anhydride containing group and each cyclic siloxane D is an 8 membered ring and it is to be understood that the X group can replace any of the Si—H groups originally positioned in the ring of each cyclic siloxane D so the main ingredient of the mixture maybe but is not necessarily the following structure.

##STR00007##

The rest being a mixture of analogous molecules in which cyclic siloxanes in the structure were 10 membered rings (approximately 40 to 45%) and the remainder (approximately >0-5%) were cyclic siloxanes with 12 membered rings. The total amount adding up to 100%

[0152] The composition was cured for 5 mins at 150° C. and the seam thickness was 1 mm. The results are provided in Tables 5a (polyester) and 5d (nylon 66) below.

TABLE-US-00008 TABLE 5a Adhesion test on a 470 dtex polyester substrate. Peak Load/Width Cohesive Additive Treatment (kN/m) failure (%) Additive 2 Plasma 5.9 100 Additive 2 None 5.7 100

[0153] It can be seen that adhesion was achieved with the anhydride version of X using a without plasma treatment.

[0154] The same test were also undertaken using Additive 2 and Additives 3 and 4 which were two further compounds comprising epoxy groups:—

In Additive 3 which was a mixture of component (D) structures prepared following the process described in PCT/US19/064350, comprising a majority of molecules (approximately e.g. 51 to 55%) having a structure wherein [Y] is a polymethylphenylsiloxane chain, e is 1, d is zero, m is 2, a is 1 and the value of n is an average between 6 and 7, and each cyclic siloxane D is an 8 membered ring, each X is an epoxy containing group and it is to be understood that the X group can replace any of the Si—H groups originally positioned in the ring of each cyclic siloxane D so the main ingredient of the mixture maybe but is not necessarily the following structure

##STR00008##

The rest being a mixture of analogous molecules in which cyclic siloxanes in the structure were 10 membered rings (approximately 40 to 45%) and the remainder (approximately >0-5%) were 12 membered rings. The total amount adding up to 100%.
Additive 4 was also a mixture of component (D) structures prepared following the process described in PCT/US19/064350, comprising a majority of molecules (approximately e.g. 51 to 55%) of the equivalent same structure as additive 3 with one difference m is 1, a is 2 and as such it contained 4 epoxy groups as opposed to 2 in Additive 3 so the main ingredient of the mixture maybe but is not necessarily the following structure:

##STR00009##

The rest of Additive 4 being a mixture of analogous molecules in which cyclic siloxanes D in the structure were 10 membered rings (approximately 40 to 45%) and the remainder (approximately >0-5%). The total amount adding up to 100%.

[0155] The results using Additives 2-4 in the part B composition of Ex. 5 gave the following results.

TABLE-US-00009 TABLE 5b Adhesion test using formulation defined in Table 1 containing Add. 1 on a Nylon 66 substrate. Peak Load/Width Cohesive Additive Treatment (kN/m) failure (%) Additive 2 Plasma 5.9 98 Additive 2 None 5.0 98 Additive 3 Plasma 4.2 99 Additive 4 Plasma 5.2 99

[0156] It can be seen that adhesion was achieved with the anhydride both with and without plasma treatment on the substrate. Similar results were obtained on nylon using both epoxides.