Triazine derivative

Abstract

The invention pertains to certain (per)fluoropolyether triazine derivatives comprising at least one triazine group and at least one fluoropolyoxyalkene chain (chain R.sub.f) comprising a fluorocarbon segment having ether linkages in main chain, said chain R.sub.f comprising at least one hydroxyl group, to a method for their manufacture and to their use in lubrication, in particular for lubricating sliding or moving parts of magnetic recording media.

Claims

1. A triazine derivative of formula (T-1) or formula (T-2): ##STR00019## wherein: each of Y, Y, Y, Y, Y, Y, Y, Y equal to or different from each other, is independently a hydrocarbon group, optionally fluorinated, wherein at least one of Y, Y, Y in formula (T-1) and at least one of Y, Y, Y, Y, Y in formula (T-2) is selected from the group consisting of: groups of formula CF.sub.2CH.sub.2O(CH.sub.2CH.sub.2O).sub.sH and CF.sub.2CF.sub.2CH.sub.2O(CH.sub.2CH.sub.2O).sub.sH, wherein s and s, equal to or different from each other and at each occurrence, are integers from 0 to 5; and groups of formula CF.sub.2CH.sub.2O(CH.sub.2CH.sub.2O).sub.wJ(OH).sub.e and F.sub.2CF.sub.2CH.sub.2O(CH.sub.2CH.sub.2O).sub.wJ(OH).sub.e, wherein w and w, equal to or different from each other and at each occurrence, are integers from 0 to 5, J and J are C.sub.1-C.sub.12 hydrocarbon bridging group, optionally comprising ethereal bonds; and e and e are integers from 2 to 4; each of R.sub.F, R.sub.F, R.sub.F, R.sub.F, R.sub.F, R.sub.F, R.sub.F , R.sub.F, R*.sub.F, R**.sub.F, equal to or different from each other, is independently a divalent fluoropolyoxyalkene chain (R.sub.f) comprising repeating units R, said repeating units selected from the group consisting of: (i) CFXO, wherein X is F or CF.sub.3, (ii) CFXCFXO, wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F, (iii) CF.sub.2CF.sub.2CW.sub.2O, wherein each of W, equal to or different from each other, are selected from F, Cl, and H, (iv) CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, and (v) (CF.sub.2).sub.jCFZOwherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1C.sub.3 perfluoroalkyl group; each of E, E, E, E, E, E, E, E, E*, E**, E***, E****, equal to or different from each other, is independently a bond or a C.sub.1-C.sub.20 divalent bridging group, optionally comprising heteroatoms, optionally fluorinated, optionally further comprising one or more than one hydroxyl group; and n in formula (T-2) is zero or an integer from 1 to 5.

2. The triazine derivative of claim 1, wherein said at least one of Y, Y, Y in formula (T-1) and said at least one of Y, Y, Y, Y, Y in formula (T-2) is selected from the group consisting of: groups of formula CF.sub.2CH.sub.2OH and CF.sub.2CF.sub.2CH.sub.2OH; and groups of formula CF.sub.2CH.sub.2O(CH.sub.2CHOHCH.sub.2O).sub.dH and CF.sub.2CF.sub.2CH.sub.2O(CH.sub.2CHOHCH.sub.2O).sub.dH, wherein d and d, equal to or different from each other and at each occurrence, are integers from 1 to 3.

3. The triazine derivative of claim 2, complying with any of formula (T-1a) and (T-2a) herein below: ##STR00020## wherein: each of n1, n2, n1, n2, n1, n2, n1#, n2#, n1*, n2*, n1*, n2*, n1*, n2*, n1*, n2*, equal to or different from each other, is independently an integer from 0 to 5 each of f1, f2, f1, f2, f1, f2, f1*, f2*, f1*, f2*, f1*, f2*, f1*, f2*, f1#, f2#, equal to or different from each other, is independently an integer of 1 to 2; each of R.sub.F, equal to or different from each other and at each occurrence, is independently a divalent fluoropolyoxyalkene chain (R.sub.f); and each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group, wherein said R.sub.f is a chain comprising repeating units R, said repeating units selected from the group consisting of:
CFXO,(i) wherein X is F or CF.sub.3,
CFXCFXO,(ii) wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F,
CF.sub.2CF.sub.2CW.sub.2O,(iii) wherein each of W, equal to or different from each other, are F, Cl, and H,
CF.sub.2CF.sub.2CF.sub.2CF.sub.2O,(iv) and
(CF.sub.2).sub.jCFZO,(v) wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1-C.sub.3 perfluoroalkyl group.

4. The triazine derivative of claim 2, complying with any of formula (T-1b) and (T-2b) herein below: ##STR00021## wherein: each of n2, n2, n2, n2#, n2*, n2*, n2*, n2*, equal to or different from each other, is independently an integer from 0 to 5; each of f1, f2, f1, f2, f1, f2, f1*, f2*, f1*, f2*, f1*, f2*, f1*, f2*, f1#, f2#, equal to or different from each other, is independently an integer of 1 to 2; each of R.sub.F, equal to or different from each other and at each occurrence, is independently a divalent fluoropolyoxyalkene chain (R.sub.f); each of R.sub.H, equal to or different from each other and at each occurrence, is independently a hydrogen atom, a C.sub.1-C.sub.6 alkyl group or a (chain R.sub.f)C(O) group, in which chain (R.sub.f) is a fluoropolyoxyalkylene chain containing at least one hydroxyl group; and each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group, wherein said R.sub.f is a chain comprising repeating units R, said repeating units selected from the group consisting of:
CFXO,(i) wherein X is F or CF.sub.3,
CFXCFXO,(ii) wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F,
CF.sub.2CF.sub.2CW.sub.2O,(iii) wherein each of W, equal to or different from each other, are F, Cl, and H,
CF.sub.2CF.sub.2CF.sub.2CF.sub.2O,(iv) and
(CF.sub.2).sub.jCFZO,(v) wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1-C.sub.3 perfluoroalkyl group.

5. The triazine derivative of claim 4 wherein each of R.sub.H, equal to or different from each other and at each occurrence, is independently a group complying with formula CO(CF.sub.2).sub.f1.sup.aR.sub.F.sup.a(CF.sub.2).sub.f2.sup.aCH.sub.2(OCH.sub.2CH.sub.2).sub.n2.sup.a-G.sup.a, wherein n2.sup.a is an integer of 0 to 5 0; each of f1.sup.a and f2.sup.a is independently an integer of 1 or 2; R.sub.F.sup.a is a divalent difluoropolyoxyalkylene chain (R.sub.f) and G.sup.a is a hydroxyl-containing group, wherein said R.sub.f is a chain comprising repeating units R, said repeating units is selected from the group consisting of:
CFXO,(i) wherein X is F or CF.sub.3,
CFXCFXO,(ii) wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F,
CF.sub.2CF.sub.2CW.sub.2O,(iii) wherein each of W, equal to or different from each other, are F, Cl, and H,
CF.sub.2CF.sub.2CF.sub.2CF.sub.2O,(iv) and
(CF.sub.2).sub.jCFZO,(v) wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1-C.sub.3 perfluoroalkyl group.

6. The triazine derivative of claim 2 complying with any of formula (T-1c) and (T-2c) herein below: ##STR00022## wherein: each of n2, n2, n2, n2#, n2*, n2*, n2*, n2*, equal to or different from each other, is independently an integer from 0 to 5; each of f1, f2, f1, f2, f1, f2, f1*, f2*, f1*, f2*, f1*, f2*, f1*, f2*, f1#, f2#, equal to or different from each other, is independently an integer of 1 to 2; u is 0 or 1; each of R.sub.F, equal to or different from each other and at each occurrence, is independently a divalent fluoropolyoxyalkene chain (R.sub.f); each of R.sub.H, equal to or different from each other and at each occurrence, is independently a hydrogen atom, a C.sub.1-C.sub.6 alkyl group or a group of formula (chain R.sub.f)CF.sub.2(CH.sub.2O).sub.uCH.sub.2 or of formula (chain R.sub.f)CF.sub.2CF.sub.2(CH.sub.2O).sub.uCH.sub.2, wherein said chain R.sub.f is a fluoropolyoxyalkylene chain containing at least one hydroxyl group; each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group, wherein said R.sub.f is a chain comprising repeating units R, said repeating units selected from the group consisting of:
CFXO,(i) wherein X is F or CF.sub.3,
CFXCFXO,(ii) wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F,
CF.sub.2CF.sub.2CW.sub.2O,(iii) wherein each of W, equal to or different from each other, are F, Cl, and H,
CF.sub.2CF.sub.2CF.sub.2CF.sub.2O,(iv) and
(CF.sub.2).sub.jCFZO,(v) wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1-C.sub.3 perfluoroalkyl group.

7. The triazine derivative of claim 6 wherein each of R.sub.H, equal to or different from each other and at each occurrence, is a group of formula CH.sub.2(OCH.sub.2).sub.u(CF.sub.2).sub.f1.sup.aR.sub.F.sup.a(CF.sub.2).sub.f2.sup.aCH.sub.2(OCH.sub.2CH.sub.2).sub.f2.sup.a-G.sup.a, wherein u is 0 or 1, n2.sup.a is an integer of 0 to; each of f1.sup.a and f2.sup.a is independently an integer of 1 or 2; R.sub.F.sup.a is a divalent fluoropolyoxyalkylene chain (R.sub.f) and G.sup.a is a hydroxyl-containing group, wherein said R.sub.f is a chain comprising repeating units R, said repeating units selected from the group consisting of:
CFXO,(i) wherein X is F or CF.sub.3,
CFXCFXO,(ii) wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F,
CF.sub.2CF.sub.2CW.sub.2O,(iii) wherein each of W, equal to or different from each other, are F, Cl, and H,
CF.sub.2CF.sub.2CF.sub.2CF.sub.2O,(iv) and
(CF.sub.2).sub.jCFZO,(v) wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1-C.sub.3 perfluoroalkyl group.

8. The triazine derivative of claim 2, complying with any of formula (T-1d) and (T-2d) herein below: ##STR00023## wherein: each of n2, n2, n2, n2#, n2*, n2*, n2*, n2*, equal to or different from each other, is independently an integer from 0 to 5; each of f1, f2, f1, f2, f1, f2, f1*, f2*, f1*, f2*, f1*, f2*, f1*, f2*, f1#, f2#, equal to or different from each other, is independently an integer of 1 to 2; each of R.sub.F, equal to or different from each other and at each occurrence, is independently a divalent fluoropolyoxyalkene chain (R.sub.f); and each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group, wherein said R.sub.f is a chain comprising repeating units R, said repeating units is selected from the group consisting of:
CFXO,(i) wherein X is F or CF.sub.3,
CFXCFXO,(ii) wherein X, equal to or different at each occurrence, is F or CF.sub.3, wherein at least one of X is F,
CF.sub.2CF.sub.2CW.sub.2O,(iii) wherein each of W, equal to or different from each other, are F, Cl, and H,
CF.sub.2CF.sub.2CF.sub.2CF.sub.2O,(iv) and
(CF.sub.2).sub.jCFZO,(v) wherein j is an integer from 0 to 3 and Z is a group of general formula OR.sub.fT.sub.3, wherein R.sub.f is a fluoropolyoxyalkene chain comprising between 0 and 10 repeating units each independently selected from the group consisting of CFXO, CF.sub.2CFXO, CF.sub.2CF.sub.2CF.sub.2O, and CF.sub.2CF.sub.2CF.sub.2CF.sub.2O, with each of X being independently F or CF.sub.3, and wherein T.sub.3 is a C.sub.1-C.sub.3 perfluoroalkyl group.

9. A lubricant composition comprising a triazine derivative and at least one lubricant, wherein the triazine derivative comprises at least one triazine group and at least one fluoropolyoxyalkene chain (chain Rf) comprising a fluorocarbon segment having ether linkages in the main chain, wherein chain Rf comprises at least one hydroxyl group.

10. The lubricant composition of claim 9 comprising at least one perfluoropolyether (PFPE) lubricant comprising a perfluorooxyalkylene chain, wherein said chain comprises recurring units having at least one ether bond and at least one fluorocarbon moiety, different from said triazine derivative.

11. A method for lubricating a magnetic recording medium comprising coating on at least one of its surface a composition comprising a triazine derivative, wherein the triazine derivative comprises at least one triazine group and at least one fluoropolyoxyalkene chain (chain Rf) comprising a fluorocarbon segment having ether linkages in the main chain, wherein chain Rf comprises at least one hydroxyl group.

12. The method of claim 11, wherein the magnetic recording medium is a hard disk.

13. The triazine derivative of claim 3, wherein each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group selected from the group consisting of formula (g1), (g2) and (g3): ##STR00024##

14. The triazine derivative of claim 4, wherein each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group selected from the group consisting of formula (g1), (g2) and (g3): ##STR00025##

15. The triazine derivative of claim 6, wherein each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group selected from the group consisting of formula (g1), (g2) and (g3): ##STR00026##

16. The triazine derivative of claim 8, wherein each of G, G, G, G*, G*, G*, G*, equal to or different from each other, is independently a hydroxyl-containing group selected from the group consisting of formula (g1), (g2) and (g3): ##STR00027##

17. The triazine derivative of claim 5, wherein G.sup.a is a hydroxyl-containing group selected from the group consisting of formula (g1), (g2) and (g3): ##STR00028##

18. The triazine derivative of claim 10, wherein G.sup.a is a hydroxyl-containing group selected from the group consisting of formula (g1), (g2) and (g3): ##STR00029##

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows the comparison between the thermogravimetric analysis of the compound of example 1, according to the present invention, and the compounds of comparative examples 2-4.

EXAMPLES

Example 1

Synthesis of Triazine Derivative, Comprising Three Hydroxyl Groups

Step 1.1: Reaction of FOMBLIN ZDOL PFPE with 2,4,6-trichloro-1,3,5-triazine

(2) 600 g of FOMBLIN ZDOL PFPE of formula:
HOCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.p(CF.sub.2O).sub.qCF.sub.2CH.sub.2OH
(EW 491 g/eq; Mn1000; 1.22 eq.; polydispersity index 1.09, p/q=0.98), 200 g of acetonitrile and 3.60 g (58.57 meq) of 2,4,6-trichloro-1,3,5-triazine were charged into a 1 l round-bottomed flask, equipped with a thermometer, a magnetic stirrer, a water cooled condenser and a dropping funnel containing 16.2 g of a 48.15% w/w solution of collidine (trimethylpyridine) in acetonitrile. After cooling at 0 C. on an ice-bath, 5.4 g of this solution was added dropwise. The reaction mixture was maintained at 0 C. under stirring during 2 hours. The temperature was then raised to 20 C. and other amount of the same solution (5.4 g) was added dropwise. The reaction mixture was maintained at 20 C. under stirring during 4 hours. The remaining 5.4 g of solution was added dropwise. The temperature was raised to 80 C. and reaction mixture was maintained at this temperature under stirring during 7 hours (complete conversion). The reaction mixture was then cooled down to room temperature and a crude product was recovered by washing with 5180 g of distilled water. The solvent was removed by distillation at reduced pressure to afford 599.39 g of crude product which is a mixture of unreacted FOMBLIN ZDOL PFPE, desired product and its oligomers, i.e. its dimeric form having the following formula:

(3) ##STR00016##
with p and q having the meanings as above detailed.

Step 1.2a: Removal of Unreacted FOMBLIN ZDOL PFPE

(4) Most of unreacted FOMBLIN ZDOL PFPE was removed in three passages through molecular distillation under a residual pressure of 310.sup.3 mbar at 100 C., 105 C. and 107 C., respectively. The feed flow rate was set at about 100 g/h in all cases. Three low-viscous fractions (49.9, 24.9 and 10.7% by weight, respectively) of only FOMBLIN ZDOL PFPE (confirmed through .sup.19F-NMR analysis) were therefore removed, leaving a high boiling, low volatility residue, which was characterized by .sup.19F-NMR.

Step 1.2b: scCO2 Fractionation

(5) As an alternative to the molecular distillation technique above detailed, the crude residue was charged into a 300 ml SFT-150 Supercritical CO.sub.2 Extraction System and heated at 100 C. Through a step-by-step increase of pressure (from 150 to 300 bar) the triazine derivative bearing three hydroxyl groups and complying with following formula:

(6) ##STR00017##
with p and q having the meanings as above detailed,
was successfully isolated. The unreacted residual FOMBLIN ZDOL PFPE was easily removed at scCO.sub.2 low pressure, while certain high MW by-product oligomers were selectively collected at high pressure.

Comparative Example 1

Reaction of Monofunctional Alcohol with Trichlorotriazine

(7) 294.58 g of monofunctional alcohol PFPE having formula: HOCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.p(CF.sub.2O).sub.qCF.sub.3 (p/q=1; p and q were selected so as to obtain Mn 1000, EW 1030 g/eq.; 286 meq.), 148 g of acetonitrile, 600 g of hexafluoroxylene (HFX), 56.32 g of potassium carbonate (407.55 meq.) and 16.70 g (271.70 meq.) of 2,4,6-trichloro-1,3,5-triazine were charged into a 1 l round-bottomed flask, equipped with a thermometer, a magnetic stirrer and a water cooled condenser. The temperature was slowly raised to 80 C. and reaction mixture was maintained at this temperature under stirring during 16 hours (98% conversion by .sup.19F-NMR). After cooling down to room temperature and adding 590 g of demineralized water, HCl 37% was added dropwise until acid pH was reached. The organic phase was separated and washed three times with a 5% w/w hydroalcoholic solution of isobutanol. Solvents and unreacted monofunctional alcohol were removed by distillation at 100 C. and reduced pressure (10.sup.2 mbar) to afford 272.48 g of crude product of formula:

(8) ##STR00018##
as confirmed by .sup.19F-NMR, .sup.13C-NMR and FTIR analysis. Final product was filtered through a 0.2 m PTFE membrane.
TGA Analyses on Neat Samples or on Silica Adsorbed Samples

(9) The thermogravimetric analysis (TGA) were performed in an air atmosphere with a Perkin Elmer TGA 7 instrument in the temperature range 25-800 C. with a heating rate 10 C./min either on neat samples or on samples adsorbed on silica gel.

(10) Results from silica-adsorbed specimens were used for characterizing thermo-oxidative stability cleaned from the contribution of volatility; while neat sample TGAs compared to the TGA of adsorbed specimens, make possible to clarify the contribution of the volatility to the total weight loss. Samples adsorbed onto silica were prepared as follow: 1 g of silica gel, 0.5 g of triazine derivative and 10 g of A113 were charged into a round-bottomed flask, equipped with a magnetic stirrer. The reaction mixture was maintained at room temperature under stirring during 8 hours before removing solvent by distillation under reduced pressure.

(11) To the sake of comparison with inventive compound of example 1, following PFPE derivatives were tested in analogous conditions: the PFPE triazine derivative of comparative example 2, free from hydroxyl groups (Comp. Ex. 2); a commercially available diol derivative, namely FOMBLIN ZDOL having Mn3000 (Comp. Ex. 3); and a commercially available tetraol derivative, namely FOMBLIN Z Tetraol 3200GT, having Mn3000 (Comp. Ex. 4).

(12) So obtained TGA traces for silica-adsorbed samples are depicted in FIG. 1.

(13) After an initial plateau region in the TGA traces with the only exception of the product without OH end-groups which shows a continuous decrease of weight due to its higher volatility, a sudden drop in the mass, due to thermo-oxidative degradation, was in all cases observed. Results showed that the triazine derivative of the invention (Ex. 1), comprising three hydroxyl groups, has a higher thermo-oxidative stability compared to other derivatives.

(14) Specifically the temperatures at which a degradation corresponding to a weight loss of 10% (for both neat and silica adsorbed specimens) and at 50% (for silica adsorbed specimens) were identified for investigated compounds and are summarized in the following Tables 1 and 2, the higher the temperature values, the better the behaviour, both in terms of interaction with the support and thermo-oxidative stability. In particular, Table 1 summarizes differences in temperatures at which 10% weight loss is recorded among silica adsorbed and neat samples: this parameter is considered to represent a good indication of the ability of the lubricant derivative to interact with the substrate and then depressing negative volatility phenomena. Values in Table 1, recorded for compounds substantially having similar Mn, show higher T, thus major interaction with the substrate, for hydroxyl-containing triazine with respect to corresponding hydroxyl-free neutral triazine derivative of comparative example 2.

(15) TABLE-US-00001 TABLE 1 Sample i.d. Ex. 1 Comp. Ex. 2 Comp. Ex. 3 Comp. Ex. 4 T* (for 81 C. 37 C. 84 C. 52 C. 10% wt loss) *T: difference in temperatures at which 10% weight loss occur between silica adsorbed and neat specimens.

(16) TABLE-US-00002 TABLE 2 Sample i.d. Ex. 1 Comp. Ex. 2 Comp. Ex. 3 Comp. Ex. 4 T** for 50% wt loss 410 C. 382 C. 379 C. 379 C. **for silica adsorbed specimens.

(17) Data provided in Table 2 nicely demonstrate that thermo-oxidative behaviour of the inventive compound largely exceeds that of all other comparative materials (see Table 2), including triazine-containing but without OH end-groups (comparative example 2) and triazine-free (comparative example 3 and 4 related to conventional hydroxyl-containing lubricants) perfluoropolyether derivatives.