POLYUNSATURATED COMPOUND FOR CURING FLUOROELASTOMER COMPOSITIONS

Abstract

The invention pertains to a polyunsaturated compound having formula (I) [compound (DAIC-PFPE)]: T.sup.A-OR.sub.f-T.sup.A wherein: R.sub.f is (per)fluoropolyoxyalkylene chain [chain (R.sub.f)] comprising recurring units having at least one catenary ether bond and Sat least one fluorocarbon moiety; T.sup.A and T.sup.A, equal to or different from each other, are selected from the group consisting of: (i) C.sub.1-C.sub.24 (hydro)(fluoro)carbon groups, possibly comprising one or more than one of H, O, and Cl; and (ii) (hydro)(fluoro)carbon group comprising at least one diallylisocyanurate group of formula (A) wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 is, independently, a hydrogen atom or a C.sub.1-C.sub.3 hydrocarbon group, preferably a hydrogen atom (group T.sup.DAIC), with the provisio that at least one of T.sup.A and T.sup.A is a group T.sup.DAIC, to a process for its manufacture and its use for curing fluoroelastomers, to fluoroelastomer compositions comprising the same, as well as to a process for producing fluororubber mouldings therefrom.

##STR00001##

Claims

1. A polyunsaturated compound (DAIC-PFPE), wherein compound (DAIC-PFPE) is a compound of formula (I):
T.sup.A-OR.sub.f-T.sup.A(I) wherein: R.sub.f is (per)fluoropolyoxyalkylene chain (R.sub.f) comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety; T.sup.A and T.sup.A, equal to or different from each other, are selected from the group consisting of: (i) C.sub.1-C.sub.24 (hydro)(fluoro)carbon groups, optionally possibly-comprising one or more than one of H, O, and Cl; and (ii) (hydro)(fluoro)carbon group comprising at least one diallylisocyanurate group of formula: ##STR00024## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 is, independently, a hydrogen atom or a group T.sup.DAIC, wherein group T.sup.DAIC is a C.sub.1-C.sub.3 hydrocarbon group, with the provisio that at least one of T.sup.A and T.sup.A is a group T.sup.DAIC, as above detailed.

2. The compound (DAIC-PFPE) of claim 1, wherein chain (R.sub.f) complies with formula:
(CF.sub.2CF.sub.2O).sub.a(CF.sub.2O).sub.b(CF.sub.2(CF.sub.2).sub.zCF.sub.2O).sub.c, wherein: z is 1 or 2; a, b, c are integers 0, wherein chain (R.sub.f) exhibits a number averaged molecular weight of 500 to 6000.

3. The compound (DAIC-PFPE) of claim 2, which complies with formula (II):
T.sup.B-OR*.sub.f-T.sup.B(II) wherein: R*.sub.f is a (per)fluoropolyoxyalkylene chain (R.sub.f) comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety; each of T.sup.B and T.sup.B, equal to or different from each other, are selected from (j) a group of any of formulae CF.sub.3, CF.sub.2C.sub.1, CF.sub.2CF.sub.3, CF(CF.sub.3).sub.2, CF.sub.2H, CFH.sub.2, CF.sub.2CH.sub.3, CF.sub.2CHF.sub.2, CF.sub.2CH.sub.2F, CFZ*CH.sub.2OH, CFZ*COOH, CFZ*COOR.sub.h and CFZ*CH.sub.2(OCH.sub.2CH.sub.2).sub.kOH, wherein k is ranging from 0 to 10, Z* is F or CF.sub.3; and R.sub.h is a C.sub.1-C.sub.6 hydrocarbon chain; and (jj) a group T.sup.DAIC*, of any of formulae CFZ*CH.sub.2-DAIC, and CFZ*CH.sub.2(OCH.sub.2CH.sub.2).sub.k-DAIC, wherein k is ranging from 0 to 10, Z* is F or CF.sub.3; and DAIC is a diallylisocyanurate group of formula: ##STR00025## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 is, independently, a hydrogen atom or a C.sub.1-C.sub.3 hydrocarbon group with the provisio that at least one of T.sup.B and T.sup.B is a group T.sup.DAIC*, as above detailed.

4. The compound (DAIC-PFPE) of claim 3, which complies with formula (III):
T.sup.C-O(CF.sub.2CF.sub.2O).sub.a(CFYO).sub.b(CF.sub.2CFYO).sub.c(CF.sub.2O).sub.d(CF.sub.2(CF.sub.2).sub.zCF.sub.2O).sub.e-T.sup.C, wherein: Y is a C.sub.1-C.sub.5 perfluoro(oxy)alkyl group; z is 1 or 2; a, b, c, d, e are integers 0; each of T.sup.C and T.sup.C, equal to or different from each other, are selected from (k) a group of any of formulae CF.sub.3, CF.sub.2C.sub.1, CF.sub.2CF.sub.3, CF(CF.sub.3).sub.2, CF.sub.2H, CFH.sub.2, CF.sub.2CH.sub.3, CF.sub.2CHF.sub.2, CF.sub.2CH.sub.2F, CFZ*CH.sub.2OH, and CFZ*CH.sub.2(OCH.sub.2CH.sub.2).sub.kOH, wherein k is ranging from 0 to 10, and Z* is F or CF.sub.3; and (kk) a group T.sup.DAIC of any of formulae CFZ*CH.sub.2-DAIC, and CFZ*CH.sub.2(OCH.sub.2CH.sub.2).sub.k-DAIC, wherein Z* is F or CF.sub.3; k is ranging from 0 to 10, and DAIC is a diallylisocyanurate group of formula: ##STR00026## with the provisio that at least one of T.sup.B and T.sup.B is a group T.sup.DAIC, as above detailed.

5. A method for manufacturing a compound (DAIC-PFPE) according to claim 1, said method comprising reacting a (per)fluoropolyether precursor compound comprising a (per)fluoropolyoxyalkylene chain (R.sub.f) comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety and possessing at least one reactive chain end, with at least one compound including a diallylisocyanurate group.

6. The method of claim 5, said method including reacting a hydroxylated (per)fluoropolyether precursor compound complying with formula (VI):
J-OR.sub.f-J(IV) wherein: R.sub.f is a (per)fluoropolyoxyalkylene chain (R.sub.f) comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety and possessing at least one reactive chain end; each of J and J, equal to or different from each other, are selected from (l) groups of any of formulae CF.sub.3, CF.sub.2C.sub.1, CF.sub.2CF.sub.3, CF(CF.sub.3).sub.2, CF.sub.2H, CFH.sub.2, CF.sub.2CH.sub.3, CF.sub.2CHF.sub.2, CF.sub.2CH.sub.2F, CFZ*COOH, and CFZ*COOR.sub.h wherein Z* is F or CF.sub.3; and R.sub.h is a C.sub.1-C.sub.6 hydrocarbon chain; and (ll) hydroxyl-containing groups (J.sup.OH) of any of formulae CFZ*CH.sub.2OH, and CFZ*CH.sub.2(OCH.sub.2CH.sub.2).sub.kOH, wherein k is ranging from 0 to 10, and Z* is F or CF.sub.3, with the provisio that at least one of J and J is a group (J.sup.OH), as above detailed; with diallylisocyanurate of formula: ##STR00027## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.6 is, independently, a hydrogen atom or a C.sub.1-C.sub.3 hydrocarbon group.

7. A method for crosslinking a fluoroelastomer, comprising using compound (DAIC-PFPE), according to claim 1.

8. A (per)fluoroelastomer composition (C) comprising: a fluoroelastomer (A), wherein fluoroelastomer (A) is a (per)fluoroelastomer; and at least one compound (DAIC-PFPE), according to claim 1, said compound (DAIC-PFPE) being comprised in the composition_(C) in an amount of 0.5 to 50 phr, with respect to fluoroelastomer (A).

9. The composition (C) of claim 8, wherein fluoroelastomer (A) is selected among: (l) vinylidene fluoride (VDF)-based copolymers, in which VDF is copolymerized with at least one comonomer selected from the group consisting of: (a) C.sub.2-C.sub.8 perfluoroolefins; (b) hydrogen-containing C.sub.2-C.sub.8 olefins; (c) C.sub.2-C.sub.8 fluoroolefins comprising at least one of iodine, chlorine and bromine; (d) (per)fluoroalkylvinylethers (PAVE) of formula CF.sub.2CFOR.sub.f, wherein R.sub.f is a C.sub.1-C.sub.6 (per)fluoroalkyl group; (e) (per)fluoro-oxy-alkylvinylethers of formula CF.sub.2CFOX, wherein X is a C.sub.1-C.sub.12 ((per)fluoro)-oxyalkyl comprising catenary oxygen atoms; (f) (per)fluorodioxoles having formula: ##STR00028## wherein each of R.sub.f3, R.sub.f4, R.sub.f5, R.sub.f6, equal to or different from each other, is independently selected from the group consisting of fluorine atom and C.sub.1-C.sub.6 (per)fluoroalkyl groups, optionally comprising one or more than one oxygen atom; (g) (per)fluoro-methoxy-vinylethers (MOVE) having formula:
CF.sub.2CFOCF.sub.2OR.sub.f2 wherein R.sub.f2 is selected from the group consisting of C.sub.1-C.sub.6 (per)fluoroalkyls; C.sub.5-C.sub.6 cyclic (per)fluoroalkyls; and C.sub.2-C.sub.6 (per)fluorooxyalkyls, comprising at least one catenary oxygen atom; (h) C.sub.2-C.sub.8 non-fluorinated olefins (Ol); (i) ethylenically unsaturated compounds comprising nitrile (CN) groups, optionally (per)fluorinated; and (2) TFE-based copolymers, in which TFE is copolymerized with at least one comonomer selected from the group consisting of (c), (d), (e), (g), (h) and (i) as above detailed

10. The composition (C) of claim 8, wherein fluoroelastomer (A) comprises recurring units derived from a bis-olefin (OF) having general formula: ##STR00029## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6, equal or different from each other, are H or C.sub.1-C.sub.5 alkyl; Z is a linear or branched C.sub.1-C.sub.18 hydrocarbon radical, optionally containing oxygen atoms, and optionally at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical.

11. The composition (C) of claim 8, wherein fluoroelastomer (A) comprises iodine and/or bromine cure sites, such that the iodine and/or bromine is present in an amount of 0.001 to 10% wt, with respect to the total weight of fluoroelastomer (A).

12. The composition (C) of claim 8, wherein fluoroelastomer (A) is selected from VDF-based copolymers comprising (with respect to total moles of recurring units of fluoroelastomer (A)): from 5 to 35% moles of recurring units derived from at least one (per)fluoro-methoxy-vinylethers (MOVE) having formula:
CF.sub.2CFOCF.sub.2OR.sub.f2 wherein R.sub.f2 is selected from the group consisting of C.sub.1-C.sub.6 (per)fluoroalkyls; C.sub.5-C.sub.6 cyclic (per)fluoroalkyls; and C.sub.2-C.sub.6 (per)fluorooxyalkyls, comprising at least one catenary oxygen atom; from 0.5 to 35% moles of recurring units derived from at least one C.sub.2-C.sub.8 perfluoroolefin; with the provisio that the sum of recurring units derived from (per)fluoro-methoxy-vinylethers (MOVE) and from the perfluoroolefin is of at least 10% moles; from 0 to 5% moles of recurring units derived from a bis-olefin (OF), as above detailed; and from 90 to 30% moles of recurring units derived from VDF.

13. The composition (C) of claim 8, said composition further comprising at least one peroxide.

14. The composition (C) of claim 8, said composition comprising at least one polyunsaturated curing coagent different from (DAIC-PFPE) compound.

15. A cured article obtained by moulding and curing the composition (C) according to claim 8, wherein the cured article is selected from the group consisting of O(square)-rings, packings, gaskets, diaphragms, shaft seals, valve stem seals, piston rings, crankshaft seals, cam shaft seals, oil seals, piping, tubing, flexible hoses, and conduits for delivery of hydrocarbon fluids and fuels.

16. A method for processing the composition (C), according to claim 8, the method comprising any of injection moulding, compression moulding, extrusion moulding, coating, screen printing technique, or form-in-place technique.

17. The compound (DAIC-PFPE) of claim 2, wherein chain (R.sub.f) exhibits a number averaged molecular weight of 1000 to 4500.

18. The compound (DAIC-PFPE) of claim 3, wherein DAIC is a diallylisocyanurate group of formula: ##STR00030##

19. The composition (C) of claim 12, wherein fluoroelastomer (A) is selected from VDF-based copolymers comprising (with respect to total moles of recurring units of fluoroelastomer (A)): from 15 to 25% moles of recurring units derived from at least one (per)fluoro-methoxy-vinylethers (MOVE) having formula:
CF.sub.2CFOCF.sub.2OR.sub.f2 wherein R.sub.f2 is selected from the group consisting of C.sub.1-C.sub.6 (per)fluoroalkyls; C.sub.5-C.sub.6 cyclic (per)fluoroalkyls; and C.sub.2-C.sub.6 (per)fluorooxyalkyls, comprising at least one catenary oxygen atom; from 2 to 25% moles of recurring units derived from at least one C.sub.2-C.sub.8 perfluoroolefin selected from tetrafluoroethylene (TFE), hexafluoropropylene (HFP), hexafluoroisobutylene; with the provisio that the sum of recurring units derived from (per)fluoro-methoxy-vinylethers (MOVE) and from the perfluoroolefin is of at least 17% moles; from 0 to 2.5% moles of recurring units derived from a bis-olefin (OF), as above detailed; and from 83 to 50% moles of recurring units derived from VDF.

20. The composition (C) of claim 13, wherein the peroxide is selected from organic peroxides, dialkyl peroxides, di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, dicumyl peroxide, dibenzoyl peroxide, di-tert-butyl perbenzoate and bis[1,3-dimethyl-3-(tert-butylperoxy)butyl] carbonate.

Description

EXAMPLES

[0134] TECNOFLON PFR94 is a peroxide-curable iodine end group-containing perfluoroelastomer, comprising recurring units derived tetrafluoroethylene (TFE); and perfluoro-methylvinylether (FKM-1, hereinafter), commercially available from Solvay Specialty Polymers Italy S.p.A.

[0135] TECNOFLON VPL X75545 FKM is a peroxide-curable iodine end group-containing fluoroelastomer, comprising recurring units derived from vinylidene fluoride (VDF) 60.5% by moles; tetrafluoroethylene (TFE) 17.5% by moles; and perfluoro-methoxy-vinylethers having formula CF.sub.2CFOCF.sub.2OCF.sub.3 (MOVE3) 22% by moles (FKM-2, hereinafter), commercially available from Solvay Specialty Polymers Italy S.p.A.

Preparative Example 1

Step 1(a) Preparation of a Nonaflate Derivative of PFPE Diol [PFPE.SUP.4000.-Nonaflate]

[0136] ##STR00022##

Proportions:

[0137] Anhydrous Z-Dol 4000, comprising minor amount of non-functional and mono-functional analogous: M.sub.W=3811 g/mol; E.sub.W=1975 g/eq; 500 g; 0.131 mol; 0.253 eq OH

[0138] C.sub.4F.sub.9SO.sub.2F: 99.42 g; M.sub.W=302.19 g/mol; mol=1.30.253 eq OH Z-DOL=0.329 mol

[0139] TEA: 33.29 g; M.sub.W=101.19 g/mol; mol=1.3*0.253 eq OH Z-DOL=0.329 mol

[0140] CH.sub.2Cl.sub.2: 700 ml

Procedure:

[0141] Before beginning the synthesis, the necessary amount of Z-DOL must be dried by placing it in a round-bottomed flask and heated with magnetic stirring (900-1000 rpm) at 80 C. under vacuum (0.1 mbar PRES).

[0142] A three-necked, 1 liter round-bottomed glass reactor, equipped with a mechanical stirrer, a reflux condenser with an inert gas (N.sub.2) compensator on top to keep the system anhydrous and inert, dripping funnel and an internal thermometer, is charged with anhydrous Z-DOL (M.sub.W=3811 g/mole; E.sub.W=1975 g/eq; 500 g; 131 mmols; 253 meq) and dichloromethane. The mechanical stirrer was turned on to ca. 300 rpm, and the dishomogeneous mixture is heated to 40 C. Therefore the solution of RM-60 and TEA (dishomogeneous) was dripped in about twenty-five minutes. Following complete addition, the reaction mixture was kept at 40 C. with 300 rpm stirring under N.sub.2 for a total reaction time of 5 hours. The complete conversion in nonaflate was verified by .sup.19F-NMR of the crude reaction mixture, in particular by following the Z-DOL pre-terminal conversion.

[0143] The crude reaction mixture was transferred to an adequate separatory funnel where the lower fluorinated phase was drawn-off and it was washed 3 times with 100 ml of Ethanol at 96%. The washed nonaflate was then dried over MgSO.sub.4, filtered with 5 um PTFE membrane, and then the residual amount of solvent was evaporated at 50 C. and 0.25 mbar residual Pressure employing a mechanical pump for a total distillation time of 3 hours.

[0144] Nonaflate obtained=528.22 g of a clear, pale yellow liquid.

[0145] Terminal groups: 96.2 mol % of OCF.sub.2CH.sub.2OSO.sub.2C.sub.4F.sub.9; 0.4% mol OCF.sub.2CH.sub.2OH; Non-functional: 3.4% mol

[0146] Isolated yield=Selectivity=99.58%

[0147] Average M.sub.W=4145 g/mole.

[0148] E.sub.W=2111 g/eq

NMR Characterization

[0149] .sup.a(CF.sub.2O).sub.m.sup.b(CF.sub.2CF.sub.2O).sub.n.sup.cCF.sub.2.sup.dCH.sub.2OSO.sub.2.sup.eCF.sub.2.sup.fCF.sub.2.sup.gCF.sub.2.sup.hCF.sub.3

[0150] .sup.19F-NMR: (vs. CFCl.sub.3; ppm) a: 51; 52.5; 54.5; b: 88; 90; c: 77.5; 79.5; e: 109.2; f: 120.2; g: 125.2; h: 81.

Step 2(a) Preparation of the DAIC-PFPE Compound [DAIC-PFPE-1]

[0151] ##STR00023##

Proportions:

[0152] DIAC: 16.0 g; M.sub.W=209.09 g/mol; 0.0765 mol

[0153] PFPE.sup.4000Nonaflate: 176.06 g; M.sub.W=4145 g/mol; E.sub.W=2111 g/eq; eq=1.090.0765 mol DIAC=0.0834 eq

[0154] K.sub.2CO.sub.3: 11.53 g; M.sub.W=138.2 g/mol; 1.090.0765 mol DIAC=0.0834 mol

[0155] DMF: 100 ml

[0156] EFX: 45 ml

Procedure:

[0157] In a 1 liter, three-necked round-bottomed glass reactor, equipped with a mechanical stirrer, a reflux condenser with an inert gas (N.sub.2) compensator on top to keep the system anhydrous and inert, an internal thermometer, and a solid dispenser or dripping funnel, was charged with diallyl-isocyanurate and anhydrous dimethylformamide (DMF). The mechanical stirrer stirrer was turned on to ca. 300 rpm at 20 C. to obtain a clear colorless, homogeneous solution. Therefore K.sub.2CO.sub.3 was slowly added with the solid dispenser in ca. 35 minutes. Following complete addition, the crude-mixture solution was heated to 60 C. for 2 hours. As the acid-base reaction proceeded, the solution turned from colourless to white, opalescent, due to the isocyanurate-salt formed. At the end of the thermal treatment, the previously prepared homogeneous, transparent tan solution of PFPE.sup.4000Nonaflate (176.06 g; M.sub.W=4145 g/mol; E.sub.W=2111 g/eq; 0.0834 eq) in EFX (45 ml) are slowly dripped in 4 h with a dripping funnel. The reaction was kept at 60 C. and 300 rpm for an additional 8 hours bringing the total reaction time to 12 hours. When the stirrer was turned off, the opalescent dishomogeneous crude reaction mixture separated in two phases. The lower was the fluorinated phase and the upper was hydrogenates phase. The complete conversion of the nonaflate was verified by .sup.19F-NMR of the crude reaction mixture, in particular by measuring the concentration of C.sub.4F.sub.9SO.sub.3K salt formed in the upper-phase.

[0158] The crude reaction mixture was filtered with 5 m PTFE membrane from the formed salt. This two-phase solution obtained was transferred to an adequate separatory funnel and it was washed 2 times with aqueous 3% H.sub.3O.sup.+Cl.sup. (1:1 v/v hydrogenates:water). The final pH of the H.sub.2O layer was ensured to be below 3 for the washing to be complete.

[0159] The washed bis-diallylisocyanutate-perfluoropolyether was then dried over MgSO.sub.4, filtered with 5 m PTFE membrane, and then the residual amount of solvent was evaporated at 85 C. and 0.25 mbar residual Pressure employing a mechanical pump for a total distillation time of 2 hours.

[0160] Bis-diallylisocyanutate-perfluoropolyether obtained=150.11 g of a clear, pale yellow liquid.

[0161] Selectivity=>99 mol %.

[0162] Isolated yield=93.8 mol %

[0163] Ave. M.sub.W=5348 g/mole.

[0164] Ave. E.sub.W=2886 g/eq

NMR Analyses.

[0165] .sup.a(CF.sub.2O).sub.m.sup.b(CF.sub.2CF.sub.2O).sub.n.sup.cCF.sub.2.sup.dCH.sub.2NC(O)N(.sup.eCH.sub.2.sup.fCH.sup.gCH.sub.2)C(O)N(.sup.eCH.sub.2.sup.fCH.sup.gCH.sub.2)C(O)

[0166] .sup.19F-NMR: (vs. CFCl.sub.3; ppm) a: 52; 53.5; 55.2; b: 89; 90.5; c: 73.6; 75.4;

[0167] .sup.1H-NMR (vs TMS; ppm): d: +4.8; e: +4.65; f: +6.1; g: +5.45.

General Compounding and Curing Procedure

[0168] FKM-1 and FKM-2 were compounded with the ingredients as detailed below in a open mill. Plaques were cured in a pressed mould at 160 C. and then post-treated in an air circulating oven in conditions (1+4 hours at 230 C.).

[0169] Cure behaviour was characterized by Moving Die Rheometer (MDR), in conditions as specified below, by determining the following properties:

[0170] M.sub.L=Minimum torque (lbin)

[0171] M.sub.H=Maximum torque (lbin)

[0172] t.sub.S2=Scorch time, time for two units rise from M.sub.L (sec);

[0173] t.sub.90=Time to 90% state of cure (sec).

[0174] The tensile properties have been determined on specimens punched out from the plaques, according to the ASTM D 412 C Standard.

[0175] TS is the tensile strength in MPa;

[0176] M.sub.100 is the modulus in MPa at an elongation of 100%;

[0177] EB is the elongation at break in %.

[0178] The Shore A hardness (3) (HDS) has been determined on 3 pieces of plaque piled according to the ASTM D 2240 method.

[0179] Compression set (C-Set) values have been determined on O-rings (#214 class) according to the ASTM D 395-B method (70 hours at 200 C.).

[0180] Glass transition temperature (Tg) of cured specimens was determined according to ASTM D3418 and by TR10, determined by TR test according to ASTM D1329.

[0181] Stiction properties were evaluated according to a test method comprising: [0182] placing specimens between two sheets of Aluminium (thickness=0.1 mm) at 23 C. at a compression value of 25%; [0183] maintaining said compression value for 24 hours at 200 C.; [0184] cooling, still under compression, for 1 hour at 23 C.; [0185] releasing compression and determining maximum adhesion force by peel test (180). Lower values of maximum adhesion force (MAF, in N) are representative of specimens having improved stiction behaviour (i.e. having a non-stick behaviour towards hard substrate, even after prolonged compression at high temperature).

[0186] Curing recipe and conditions and properties of cured sample are summarized, respectively, in tables 1 and 2.

TABLE-US-00001 TABLE 1 Ingredient Ex. 1 Ex. 2C Ex. 3 Ex. 4C Ex. 5 FKM-1 wt 100 100 parts FKM-2 wt 100 100 100 parts DAIC-PFPE-1 phr 10.0 23.0 10.0 Peroxide.sup.1 phr 1.5 1.5 2.0 2.0 2.0 TAIC.sup.2 phr 5.0 5.0 5.0 C-black.sup.3 phr 15.0 15.0 30.0 30.0 30.0 Zinc Oxide.sup.4 phr 5.0 5.0 5.0 .sup.145 % active dispersion of 2,5-dimethyl-2,5-di-t-butyl-peroxy-hexane in calcium carbonate, commercially available from Arkema under tradename Luperox 101XL 45; .sup.2Triallyl isocyanurate (75 %) dispersion in silica, commercially available as Drimix TAIC 75 from Finco; .sup.3C-black N990 MT from Cancarb; .sup.4ZnO ReagentPlus from Sigma Aldrich.

TABLE-US-00002 TABLE 2 Sample Ex. 1 Ex. 2C Ex. 3 Ex. 4C Ex.5 MDR 12 min at 160 C. M.sub.L (lbxin) 0.3 0.5 0.3 0.9 0.5 M.sub.H (lbxin) 25.3 27.5 20.1 24.2 23.8 t.sub.s2 (s) 41.0 38.0 72.0 51.0 64.0 t.sub.90 (s) 186.0 144.0 285.0 190.0 232.0 Properties of cured specimen TS (MPa) 14.2 19.0 10.7 12.0 14.7 M.sub.100 (MPa) 7.3 11.1 5.1 5.7 7.8 E.B. (%) 149 135 161 160 162 HDS Shore 70 74 64 68 67 A C-Set (%) 40.1 25.9 28.5 19.6 20.8 TR test ( C.) 7 2 48.0 44.0 T.sub.g ( C.) 46.0 46.3 Stiction Properties MAF (N) 198 344