NL1001472C2 - Bifunctional per:fluoro:polyether oil - Google Patents

Abstract

Bifunctional perfluoropolyether oil is prepared by reacting a perfluoropolyether diol oil of weight average molecular weight 1500-3000 with a chain lengthener selected from diacid chlorides and diisocyanates. Also claimed is perfluoropolyether rubber prepared from derivatised perfluoropolyether diol oil chain lengthened as above in which the OH terminal groups are derivatised with a compound selected from acryloyl chlorides, isocyanate acrylates of formula O=C=N-CH2-O-C(O)-C(R1)=C(R2)(R3) (II) or with a compound of formula O=C=N-[CH2]q-Si[OR4]3 (III), whereafter the derivatised compound is crosslinked under the influence of a suitable catalyst. p = 1-5; R1, R2, R3 = H, lower alkyl (methyl, ethyl, n- or iso-propyl , n-butyl or t-butyl) q = 1-4; and R4 = methyl, ethyl, n-propyl or isopropyl

Description

Océ-Nederland B.V., in Venlo

The invention relates to difunctional perfluoropolyether oils and rubbers prepared with the aid of this oil. Such oils are known from D. Sianesi, Organofluorine Chemistry 1995, page 435. The properties of perfluoropolyether oils are very favorable for use as oils, lubricants in car washes, etc. The functional oils are suitable as an intermediate in the preparation of rubbers, adhesive coatings and the like. A drawback, however, is that these oils have a relatively low molecular weight, which limits their applicability. The object of the invention is to provide difunctional perfluoropolyether diols via a simple synthesis route with significantly higher molecular weights.

This object is achieved by extending lower molecular difunctional perfluoropolyether diols with a chain extender selected from the group: diisocyanates and diacid chlorides.

In an embodiment of the invention, a difunctional diisocyanate perfluoropolyether oil is used as the diisocyanate chain extender. The resulting difunctional perfluoropolyether oils may have OH or NCO end groups depending on the diol: diisocyanate ratio. Assuming molecular weights of 2,000 * 2,500 for the starting diol and starting diisocyanate, molecular weights of chain extended perfluoropolyether oils from about 6,000 to about 25,000 may be easily achievable.

In another embodiment of the invention, as diacid chloride is 25

O r n O

c-i ch21— c '

Cl L J n Cl with n = 0-4 and preferably glutoryl dichloride used as chain extender. Starting from a molecular weight between 2,000 and 2,500 of the starting diol, molecular weights of chain-extended perfluoropolyether oils between 4,000 and 25,000 are possible.

After cross-linking to a rubber, these extended difunctional perfluoropolyether oils are extremely suitable as a top layer of rubber in, for example, fixing devices in so-called hot roll fusers, as a top layer rubber on an intermediate medium as described in EP 0 581 355, as adhesive coatings, as release coatings, 100 1 A7 2 2 and so on. After curing they are also suitable as an antiwetting coating for nozzle plates of inkjet printheads.

This cross-linking can take place in various ways. One way is to derivatize the functional end groups of the chains in such a way that curing under the influence of light, heat and / or moisture becomes possible.

In a first embodiment of the rubber crosslinking process, the OH groups are esterified with an acryloyl chloride in a chain-extended perfluoropolyether diol oil.

The cross-linking then takes place with UV light in the presence of a photoinitiator at higher temperatures. The cross-linking can also take place by heating in the presence of a peroxide.

In a second embodiment of the rubber cross-linking method, in a chain-extended perfluoropolyether diol HO-pfpe-OH, the OH groups are converted with a urethane acrylate compound, such as 15 = C = N C2H7-0 C C-CH2 into o ch3 r OH η

20 II I

perfluoropolyether Pf Pe c— N ~ C2HËT CH2 O CHo 6 2

Cross-linking then takes place in the same manner as in the first embodiment.

Suitable catalysts for the curing of urethane perfluoropolyethers are dibutyltin dilaurate, ditbutyltin oxide, various iron derivatives such as ferroacetylacetonate, tertiary amines, etc. in amounts from 0.001 to 2% by weight.

Perfluoropolyethers with (meth) acrylate or urethane (meth) acrylate end groups can be cross-linked with 1) using peroxides such as dibenzoyl peroxide, 2,5-bis (ter-ebutylperoxy) -2,5-dimethylexane, ter-butylperoxybenzate, benzophenone, etc. in amounts of 0.1 to 3 weight percent in combination with heat (> 100 ° C) and 35 2) using photoinitiators such as α, α-diethoxyacetophenone, o-nitrobenzenediazonium hexafluoroantimonate, fluorenone, triphenylamine, benzoalkyl ethers, carbazole, etcetera combination with UV light.

1001472 3

Acrylate reactive perfluoropolyethers according to the invention are particularly suitable as additives to improve surface properties (non-wetting, antistatic) in UV or EB (electron beam curing) curing coatings based on various acrylates or methacrylates. Applications are in the field of paper coatings, coating of plastics and glass objects and the like.

In a third embodiment, the OH groups of a chain-extended perfluoropolyether diol are converted by 10 to 0 = C = N- ^ CH2J— Si | ojj perfluoropolyether 15 o— c— N-f CH ^ - s i [OETj

Then the cross-linking takes place under the influence of a catalyst such as tin octate with water and under temperature increase. These rubbers can be air cured easily. One of the special advantages of these transparent rubbers is the good conductivity. A thin layer of perfluoropolyether rubber according to the invention is not or hardly rechargeable, even after prolonged charging (up to 1 kV).

Surprisingly, it has been found that perfluoropolyethers as described above with 25 -NH-C (0) sequences in the end group, such as triethoxysilyl and urethane acrylate, are preferably chain-extending with a linker giving rise to C = 0 or other polar groups in the backbone , exhibit a surface resistance of the order of 108-109 Q.cm. This is a factor of 100-1000 lower than the surface resistance of perfluoropolyethers based on urethane cross-linking 30 (1012 Q.cm) and various other unfilled elastomers, such as (fluorine) silicone rubber.

This property renders the layers based on the mentioned perfluoropolyethers intrinsically antistatic.

Possible applications lie in the use of these layers as transparent top layers on intermediates as disclosed in EP 0 581 355, 35 transparent conductive toner coatings, transparent no-stick coatings on photoconductors and other imaging media, as mentioned for example in US 5 319 334, on transport rollers and the like. Applications where 1001472 4 transparency and guidance are required, such as in the automotive industry, the carpet industry and optical instruments, are also possible.

To further improve the mechanical properties, it is possible to crosslink mixtures of reactive end-chain chain-extended perfluoropolyether 5 oils. The correct properties of the reactants allow the elastic properties and tear strength to be controlled.

The inventions will now be further described by means of a few examples.

Example 1 The chain extension of lower molecular OH-determined perfluoropolyether oils is carried out in a three-necked flask equipped with overhead stirrer, dropping funnel (with gas bypass) and a ball cooler as follows. The flask is continuously purged with nitrogen. 500 grams of OH-terminated perfluoropolyether oil, HO-perfluoropolyether-OH, with a mass average molecular weight, Mw = approx. 2150 g / mol, are weighed into the three-necked flask. 10.2 grams of glutaryl dichloride are added dropwise via the dropping funnels in an hour at 0 ° C with stirring.

After 24 hours at 100 ° C, a viscous, almost clear, light orange liquid was obtained. This oil, 20 o o

HO-pfpe-o-c-CH2-c-O-pfpe-OH

J 3 25 can be converted into rubber in the same manner as in example 2. Also, the above reaction can be repeated by reacting the product of the reaction again with glutaryl dichloride under the same conditions.

1 00 1472 5

This creates f,, r f,, f HO- pfpe— o- C— [CH ^ - c O- pfpe O C— [CH2J C O— 3 3 f f

pfpe OC-1 CHyJ C

3

This compound theoretically has an Mw of about 8900 g / mol. In practice, depending on the reaction temperature, Mw's of 6,500 (100 ° C, 24 hours) and 11,000 (160 ° C, 24 hours) were found. This oil, too, can be extended in the same manner by reacting the product again with glutaryl dichloride at 100 ° C for 24 hours.

For example, an OH-terminated perfluoropolyether oil with an Mw of 11,000 and upon reaction at 160 ° C with a Mw of 25,000 g / mol was synthesized.

All these oils can be converted into a rubber in the manner according to example 2.

Example 2

In a 250 ml four-necked flask with stirrer, nitrogen inlet, sealed dropping funnel (with gas bypass) and a ball cooler, 98.1 grams (11.2 mmol) of perfluoropolyether diol (HO-perfluoropolyether-OH), 25 grams of 1.1.2 trifluorotrichloroethane and 5 grams of triethylamine in an ice bath cooled to 0 ° C. In the dropping funnel, 3 grams (33.1 mmole) of acryloyl chloride, ch7 = ch-20 ^ Cl, was dissolved in 40 grams of 1,1.2 trifluorotrichloroethane. This solution is added dropwise to the mixture in the four-necked flask with stirring. The white-yellow dispersion formed is kept at 55 ° C for 1 hour after which time 50 ml of ethanol are added. The resulting bright yellow mixture is then stirred at 50 ° C for 15 min after which it is cooled. The acrylic terminated oil obtained in this way is washed with a 1,1,2-trifluorotrichloroethane / ethanol mixture. After evaporation of the solvents, 87 grams (yield 88%) of 1001472 6 a clear light brown acrylic terminated oil remains.

H 0 O H

5 H2C = C c- O-pfpe- O - C— C = ch2

This oil is mixed with a photo-initiator, 20 μΙ 2,2 diethoxyacetophenone per 10 grams of acrylate-terminated oil.

This mixture is applied as a top layer on a metal cylinder, which is provided with an approximately 20 mm thick layer of peroxide hardened silicone rubber. The approximately 60 µm thick top layer is then cured under a nitrogen atmosphere with the aid of a UV lamp. The resulting clear rubber is strong and elastic. The glass transition temperature of the rubber is approx. -125 ° C.

15 Example 3

Chain extension based on a urethane reaction has been carried out in a 250 ml reaction vessel with overhead stirrer, nitrogen inlet and thermometer.

Beforehand, 50.6 grams of OCN perfluoropolyetherl'NCO with an Mw of 2562 g / mol, 89.3 grams of HO perfluoropolyether "-OH with an Mw of 2258 g / mol and 1.5 grams of 1 Mn 20 catalyst solution 1W% solution (dibutyltin dilaurate in 1,1,2 trichlorofluoroethane).

This reaction mixture is heated at 75 ° C under nitrogen for one hour.

The resulting extended perfluoropolyether oil,

25 O H H O

II II I i I I II

HO- pfpe OC N pfpe- N— C ~ O- pfpe- OH

was then provided with acrylic 30 end groups via the method of Example 1. With the aid of benzoyl peroxide and heat, the oil, provided with 2.5% carbon black, was finally converted into a top layer rubber. The mixture with benzoyl peroxide was placed on a substrate in an approximately 60 µm thick layer.

The layer was then cured at a temperature of about 140 ° C.

Example 4 In the same manner as in Example 3, a rubber is made using the perfluoropolyether diol an 80:20 mixture of a perfluoropolyether

Ho-Pfpe-OH

1001472 7 and a perfluoropolyether tetraol.

CH2OH CltoÖ H2C 0 CH2 F2C pfp6 CF2CH2 O CH2 ci {oij— ch2 och

Due to the presence of the tetraol perfluoropolyether, the crosslink density after cross-linking with, for example, acrylate groups in the resulting rubber, is increased, whereby the rubber hardness is increased.

5 Example 5

184.1 grams of perfluoropolyether diol with an Mw of approximately 2,200, 19.55 grams of 2-iso cyanatoethyl methacrylate in a three-necked flask with cooler, stirrer and nitrogen isolate

10 C

II

0 = C = N-C 2 H-0-C-C = CH 2 CH 3 and 0.11 gram of dibutyl dilaurate stirred at room temperature for 4.5 hours. The product obtained is fed via work-up with 1,1,2-trifluorotrichloroethane with 20 µl of diethoxy acetophenone per 10 grams of perfluoropolyether oil. The product is then cured in a mold under a nitrogen atmosphere using a UV lamp (UV-C: wavelength approximately 360 nm).

After about 15 minutes, a well-cured clear, anti-static rubber is obtained.

Example 6 61.85 grams of chain extended perfluoropolyether diol according to Example 2 with an Mw of about 11,000, 2.95 3- (triethoxysilyl) propyl isocyanate and 0.65 grams of catalyst solution (1w% dibutyphindilaurate in tetrahydrofuran) is stirred at room temperature for 15 hour. NMR analysis on the resulting clear oil indicates that the OH groups of the chain extended perfluoropolyether diol have been completely converted.

The oil was then mixed with 1 w% tin octate. The resulting mixture 30 was applied in an approximately 60 µm thick layer to a fabric belt provided with approximately 2.5 mm peroxide cured silicone rubber. This perfluoropolyether layer was air cured for about 4 hours. The resulting tack-free clear rubber had good viscoelastic properties.

1 00 1 47 2

Claims (5)

A multifunctional perfluoropolyether oil, characterized in that the oil is prepared by reacting a perfluoropolyether diol oil of a weight average molecular weight (mw) between 1,500 and 3,000 with a chain extender from the group of diacid chlorides and disiocyanates. A multifunctional perfluoropolyether oil according to claim 1, characterized in that a difunctional diisocyonate perfluoropolyether oil is used as the diisocyanate. A multifunctional perfluoropolyether oil according to claim 1, characterized in that a diacid chloride of the molecular formula OO Cl »cl 15 with n = 0-4 is used as chain extender. A multifunctional perfluoropolyether oil according to claim 3, characterized in that glutaryl dichloride is used as diacid chloride. Perfluoropolyether rubber, characterized in that the rubber is prepared from a derivatized chain-extended perfluoropolyether diol oil according to any one of claims 1 to 4, wherein the OH end groups are derivatized with a compound from the group of acryloyl chloride isocyanatocrylates according to the molecular formula / R1 25 0 = C = Nf CH J— O- C- C— CL Jp "I \ 0. R3 where p = 1-5 and R 1, R 2 and R 3 together may be independently selected from H and a lower alkyl group selected from the group methyl, ethyl, n-propyl, isopropyl, n-butyl and t-butyl and wherein p = 1-3, or with a compound from the series O = C = N - (CH2) q - Si (OR4) 3 where q = 1-4 and R4 can be selected from the group methyl, ethyl, n-propyl , i-propyl, after which these derivatized perfluoropolyether oils are cross-linked under the influence of a suitable catalyst. 1001472 ΠΜΓΓνΠ I DC J nCrrCMUC • i NOVELTY NUMBER OF INTERNATIONAL TYPE IDENTIFIKAT1E OF OE NATIONAL APPLICATION Characteristic of the applicant ol van d · gemaenogoe 9527 Neoeitanase application nr. Date of net intoxication for an intoxication of intemaoonaa type By oe insanoe for Intemaoonaai Onoerzoex (ISA) to net intoxication of an intoxication of intemaoonaai type tsegexeno nr. SN 26620 EN I. CLASSIFICATION OF THE SUBJECT (when applying verscnilienae oassificcaoesym all. ) According to Intamaoonaie classification (IPC) Int.Cl.6: C 08 G 18/50, C 08 F 20/28, C 08 F 20/36, C 08 G 63/682, C 08 G 65/00 II. AREAS OF TECHNIQUE EXAMINED _Onaerzocnte minimum aocumemane _I Classification system Classtficatiesvmpolen_ | Int.Cl.6; C 08 G Untrue anoere ooeumenaoe oe minimum documenaoe insofar as primal aocumenan m ae unaerzocnte coexisted III.I NO RESEARCH POSSIBLE FOR CERTAIN CONCLUSIONS (remarks on supplementary sheet) j IV.1_; LACK OF UNIT OF INVENTION (oomerxmgen oo supplementDlad)! (^ = srm PC-.:s^::iia! CS tss-i BAD original