Organohydrogenpolysiloxane having perfluoropolyether blocks and method for producing the same

Abstract

The present invention provides an organohydrogenpolysiloxane. It has excellent compatibility with organopolysiloxane, and has an organohydrogensiloxy unit that can undergo a hydrosilylation reaction with an alkenyl group, and has a perfluoropolyether block that can easily control the content of the organohydrogensiloxy unit and the siloxane. The organohydrogenpolysiloxane is represented by formula (1) and has a perfluoropolyether block. [In the formula, Rf is a perfluoropolyether block, W1 is independently a divalent organopolysiloxane block, W2 is independently a monovalent organopolysiloxane block, the number of hydrogensiloxane units in W1 and W2 cannot be 0 at the same time, Q is a divalent linking group that optionally contains at least one of an oxygen atom and a nitrogen atom, and g is a number greater than 0.

Description

Technical Field

[0001] The present invention relates to an organohydrogenpolysiloxane having a perfluoropolyether block and an organopolysiloxane moiety at both ends of the molecular chain and having excellent compatibility with an organopolysiloxane, and a method for producing the same. Background Art

[0002] In general, compounds containing perfluoropolyether groups have very low surface free energy, thus having chemical resistance, lubricity, mold release, water and oil repellency, etc. Utilizing their properties, they are widely used in industry as lubricants for magnetic recording media, oil repellents for precision instruments, mold release agents, water and oil repellents and antifouling agents for paper, fiber, glass, resin, etc., cosmetics, and protective films.

[0003] However, relevant researchers pointed out that compounds containing perfluoropolyether groups have low surface free energy, and thus show very low compatibility and affinity with other substances. If compounds containing perfluoropolyether groups are added to various industrial materials to impart the above-mentioned properties, problems will arise in terms of dispersion stability, etc. Therefore, compounds containing perfluoropolyether groups are difficult to be formulated into various industrial materials.

[0004] On the other hand, polysiloxane compounds also have properties such as water resistance, lubricity, and mold release due to their low surface free energy. However, compared with perfluoropolyether compounds, polysiloxane compounds have better affinity for other substances, and dispersion stability can be further improved by performing various modifications. Therefore, polysiloxane compounds can be added to various industrial materials and easily impart the properties of silicone, and are used as additives for performance improvement in a wide range of fields. As a compound having a perfluoropolyether group and a polysiloxane chain, there is a perfluoropolyether-modified polysiloxane compound (Patent Documents 1 to 4).

[0005] However, if the fluorine modification rate is increased by improving the properties of the perfluoropolyether group, the affinity for other industrial materials is significantly reduced, which may cause problems in dispersion stability, etc. In view of this, a perfluoropolyether-organopolysiloxane block copolymer has the characteristics of both perfluoropolyether and polysiloxane and has excellent affinity with other industrial materials (Patent Documents 5 and 6).

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2006-321764

[0009] Patent Document 2: Japanese Patent Application Publication No. 2008-308628

[0010] Patent Document 3: Japanese Patent Application Publication No. 2008-88412

[0011] Patent Document 4: Japanese Patent Application Publication No. 2009-215358

[0012] Patent Document 5: Japanese Patent Application Publication No. 2009-132826

[0013] Patent Document 6: Japanese Patent Application Publication No. 2011-21158 Summary of the invention

[0014] Problem that the invention aims to solve

[0015] The perfluoropolyether-organopolysiloxane block copolymers disclosed in Patent Documents 5 and 6 have good affinity with organopolysiloxanes, but since they do not have hydrosilyl groups, they cannot be crosslinked by hydrosilylation reaction with organopolysiloxanes having alkenyl groups, thereby failing to obtain organosilicon elastomers having perfluoropolyether groups.

[0016] In addition, the organohydrogenpolysiloxane having a perfluoropolyether group described in Patent Document 4 has a low siloxane content in the molecule and lacks compatibility with the organopolysiloxane, which sometimes produces an uneven portion or a turbid portion in the cured product obtained by the hydrosilylation reaction with the organopolysiloxane having an alkenyl group, which may have an adverse effect on the optical properties. In addition, it is difficult to control the content of the organohydrogensiloxy unit that affects the mechanical properties of the cured product, which makes it difficult to control the mechanical properties of the cured product.

[0017] Therefore, an object of the present invention is to provide an organohydrogenpolysiloxane having a perfluoropolyether block, wherein the organohydrogenpolysiloxane having a perfluoropolyether block has a perfluoropolyether group, has excellent compatibility with an organopolysiloxane, has an organohydrogensiloxy unit capable of undergoing a hydrosilylation reaction with an alkenyl group, and the contents of the organohydrogensiloxy unit and the siloxane unit are easily controlled, and a method for producing the same.

[0018] Solutions to the problem

[0019] That is, the present invention is the following invention.

[0020] <1> An organohydrogenpolysiloxane having a perfluoropolyether block represented by the following formula (1), wherein:

[0021]

[0022] In formula (1),

[0023] Rf is a perfluoropolyether block represented by the following formula (2),

[0024] -C z F 2z (OCF2) v (OC2F4) w (OC3F6) x (OC4F8) y OC z F 2z - (2)

[0025] In formula (2), z is an integer of 1 to 4, v, w, x and y are numbers of 0 to 200, respectively, v+w+x+y=3 to 200, each repeating unit can be a straight chain or a branched chain, and the arrangement of each repeating unit is not limited and can be random or block.

[0026] W1 are each independently a divalent organopolysiloxane block represented by the following formula (A),

[0027]

[0028] In formula (A), R 1 are independently an alkyl group or a phenyl group having 1 to 4 carbon atoms, h and i are independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block.

[0029] W2 are each independently a monovalent organopolysiloxane block represented by the following formula (B),

[0030]

[0031] In formula (B), R 1 are independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, R 2 are each independently an unsubstituted or substituted monovalent hydrocarbon group or a hydrogen atom having 1 to 18 carbon atoms and having no aliphatic unsaturated bond, j and k are each independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block,

[0032] However, the number i of the hydrogen siloxane units of formula (A) and the number k of the hydrogen siloxane units of formula (B) cannot be 0 at the same time.

[0033] Q is a divalent linking group optionally containing at least one of an oxygen atom and a nitrogen atom. In the above formula (1), Q is bonded to any one of the terminal carbon atom of Rf, the terminal silicon atom of W1, or the terminal silicon atom of W2.

[0034] g is a number greater than or equal to 0.

[0035] <2> according to <1> The organohydrogenpolysiloxane having a perfluoropolyether block,

[0036] The number average molecular weight is 2,000 to 500,000, and the organopolysiloxane content in one molecule is 35% or more.

[0037] <3> according to <1> or <2> The organohydrogenpolysiloxane having a perfluoropolyether block, wherein:

[0038] The perfluoropolyether block represented by Rf is a group represented by the following formula (10),

[0039] -CF2(OCF2) v (OC2F4) w OCF2- (10)

[0040] In formula (10), v and w are numbers from 0 to 200 respectively, but v+w=3 to 200. The repeating unit of (OC2F4) can be a straight chain or a branched chain, and the arrangement of each repeating unit is not limited and can be random or block.

[0041] <4> A method for producing an organohydrogenpolysiloxane having a perfluoropolyether block represented by formula (1),

[0042] It has a mixture of (a) a perfluoropolyether-organopolysiloxane block copolymer represented by the following formula (11),

[0043] (b) organohydrogenpolysiloxane and

[0044] (c) an acid catalyst to carry out an exchange reaction between the siloxanes of (a) and (b),

[0045]

[0046] In formula (11), Rf is a perfluoropolyether block represented by the following formula (2):

[0047] -C z F 2z (OCF2) v (OC z F4) w (OC3F6) x (OC4F8) y OC z F 2z - (2)

[0048] In formula (2), z is an integer of 1 to 4, v, w, x and y are numbers of 0 to 200 respectively, v+w+x+y=3 to 200, each repeating unit can be a straight chain or a branched chain, and the arrangement of each repeating unit is not limited and can be random or block.

[0049] W3 are each independently a divalent organopolysiloxane block represented by the following formula (C),

[0050]

[0051] In formula (C), R 1 are each independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, and c is each independently a number from 0 to 1000,

[0052] W4 are each independently a monovalent organopolysiloxane block represented by the following formula (D),

[0053]

[0054] In formula (D), R 1 are independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, R 2 are each independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms or a hydrogen atom without an aliphatic unsaturated bond, and d is each independently a number from 0 to 1000,

[0055] Q is a divalent linking group optionally containing at least one of an oxygen atom and a nitrogen atom, and in the above formula (11), Q is bonded to any one of the terminal carbon atom of Rf, the terminal silicon atom of W3, or the terminal silicon atom of W4,

[0056] e is a number greater than or equal to 0.

[0057]

[0058] In formula (1), Rf is a perfluoropolyether block represented by the following general formula (2):

[0059] -C z F 2z (OCF2) v (OC2F4) w (OC3F6) x (OC4F8) y OC z F 2z - (2)

[0060] In formula (2), z is an integer of 1 to 4, v, w, x and y are numbers of 0 to 200 respectively, v+w+x+y=3 to 200, each repeating unit can be a straight chain or a branched chain, and the arrangement of each repeating unit is not limited and can be random or block.

[0061] W1 are each independently a divalent organopolysiloxane block represented by the following formula (A),

[0062]

[0063] In formula (A), R 1 are independently an alkyl group or a phenyl group having 1 to 4 carbon atoms, h and i are independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block.

[0064] W2 are each independently a monovalent organopolysiloxane block represented by the following formula (B),

[0065]

[0066] In formula (B), R 1 are independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, R 2 are each independently an unsubstituted or substituted monovalent hydrocarbon group or a hydrogen atom having 1 to 18 carbon atoms and having no aliphatic unsaturated bond, j and k are each independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block,

[0067] However, the number i of the hydrogen siloxane units of formula (A) and the number k of the hydrogen siloxane units of formula (B) cannot be 0 at the same time.

[0068] Q is a divalent linking group optionally containing at least one of an oxygen atom and a nitrogen atom. In the above formula (1), Q is bonded to any one of the terminal carbon atom of Rf, the terminal silicon atom of W1, or the terminal silicon atom of W2.

[0069] g is a number greater than or equal to 0.

[0070] <5> according to <4> The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block, wherein:

[0071] The component (b) is at least one selected from 1,3,5,7-tetramethylcyclotetrasiloxane and 1,3,5,7,9-pentamethylcyclopentasiloxane.

[0072] <6> according to <4> or <5> The method for producing the organohydrogenpolysiloxane having a perfluoropolyether block,

[0073] In formula (11), e is 0.

[0074] <7> according to <4> ~ <6> The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block as described in any one of the preceding claims,

[0075] The present invention relates to a production method in which (d) an organopolysiloxane having no organohydrogensiloxy unit is further added to the components (a), (b) and (c) in the exchange reaction step, wherein the exchange reaction step is a step of performing an exchange reaction between the siloxanes (a), (b) and (d).

[0076] <8> according to <4> ~ <7> The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block according to any one of the preceding claims, wherein

[0077] (c) The acid catalyst is at least one selected from sulfuric acid, methanesulfonic acid and trifluoromethanesulfonic acid.

[0078] Effects of the Invention

[0079] The organohydrogenpolysiloxane of the present invention is easily compatible with organopolysiloxane because it has a perfluoropolyether group, a high siloxane content, and siloxane blocks at both ends of the molecular chain. In addition, since it can be hydrosilylated with an organopolysiloxane having an alkenyl group, it is difficult to produce uneven parts or white turbid parts in the obtained cured product.

[0080] Furthermore, since the content of the organohydrogensiloxy unit in the organohydrogenpolysiloxane of the present invention can be easily controlled, the mechanical properties of the cured product can also be controlled. DETAILED DESCRIPTION

[0081] The organohydrogenpolysiloxane of the present invention is represented by the following formula (1), and contains perfluoropolyether blocks (Rf) and organopolysiloxane blocks (W2 or W1) alternately.

[0082]

[0083] Since W2 or W1 has an organohydrogensiloxy unit, the organohydrogenpolysiloxane of the present invention represented by formula (1) can be hydrosilylated with an organopolysiloxane having an alkenyl group.

[0084] The organohydrogenpolysiloxane of formula (1) preferably has an organopolysiloxane content of 35% or more and 99% or less, more preferably 50% or more and 90% or less in one molecule. If the siloxane content is above the lower limit, the compatibility with the organopolysiloxane is excellent; if the siloxane content is below the upper limit, the properties of the perfluoropolyether group are easily expressed, which is preferred. The siloxane content is 10% or more of the organohydrogenpolysiloxane of formula (1). 1In the H-NMR spectrum, the molar ratio of the perfluoropolyether block Rf with a known molecular weight to the organosiloxy unit is obtained from the integrated ratio of the peak of the alkylene group from Q in the formula (1) to the peak of the alkyl group and / or phenyl group on the silicon atom, and the molar ratio is converted into a ratio of molecular weight to calculate the value. It should be noted that, generally, the organohydrogenpolysiloxane of the formula (1) has a distribution in structure, and therefore, the siloxane content is an average value per molecule.

[0085] At least one of the organopolysiloxane blocks W1 and W2 has an organohydrogensiloxy unit represented by the following formula (3).

[0086]

[0087] In formula (3), R 1 It is an alkyl group having 1 to 4 carbon atoms or a phenyl group, and among them, a methyl group is preferred.

[0088] The organohydrogensiloxy unit is present in the formula (1) at least one, preferably three or more. It should be noted that the groups of the formula (3) in the organopolysiloxane block W1 and the organopolysiloxane block W2 may be different from each other.

[0089] The divalent organopolysiloxane block W1 is a group represented by the following general formula (A).

[0090]

[0091] In formula (A), R 1 Each is independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, preferably a methyl group or a phenyl group. h and i are each independently a number from 0 to 1000, preferably a number from 0 to 500. It should be noted that the arrangement of each repeating unit is not limited and may be random or block.

[0092] Examples of the group represented by the formula (A) include groups represented by the following formulae (4) to (6). However, the group represented by the formula (A) is not limited to the groups represented by the following formulae.

[0093]

[0094] The monovalent organopolysiloxane block W2 is a group represented by the following general formula (B).

[0095]

[0096] In formula (B), R 1 Each of R is independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, preferably a methyl group or a phenyl group. 2Each is independently an unsubstituted or substituted monovalent hydrocarbon group or a hydrogen atom having 1 to 18 carbon atoms and having no aliphatic unsaturated bond; preferably an unsubstituted alkyl group having 1 to 18 carbon atoms; more preferably a methyl group, n-butyl group, n-hexyl group, n-octyl group, n-octadecyl group, or a hydrogen atom; further preferably a methyl group, n-butyl group, n-hexyl group, or a hydrogen atom. j and k are independently a number of 0 to 1000, preferably a number of 0 to 500. It should be noted that the arrangement of each repeating unit may be random.

[0097] In addition, the number i of the hydrogen siloxane unit of formula (A) and the number k of the hydrogen siloxane unit of formula (B) cannot be 0 at the same time, that is, in the organohydrogenpolysiloxane of formula (1), it is characterized in that there must be a hydrogen atom bonded to the silicon atom, which is preferably i+k=2~200.

[0098] Examples of the group represented by the formula (B) include groups represented by the following formulae (7) to (9). However, the group represented by the formula (B) is not limited to the groups represented by the following formulae.

[0099]

[0100] The perfluoropolyether block (Rf) is a block in which a plurality of repeating units represented by the following general formula are bonded.

[0101] -C r F 2r O-

[0102] However, r is an integer of 1 or more, preferably 1-4.

[0103] The perfluoropolyether block may be a block in which two or more types of these repeating units are bonded, and is represented by the following general formula (2).

[0104] -C z F 2z (OCF2) v (OC2F4) w (OC3F6) x (OC4F8) y OC z F 2z - (2)

[0105] In formula (2), z is an integer of 1 to 4, and v, w, x and y are each a number of 0 to 200, preferably 0 to 50, but v+w+x+y=3 to 200, preferably v+w+x+y=10 to 50. Each repeating unit may be a straight chain or a branched chain, and each repeating unit may be randomly bonded to each other.

[0106] Examples of the repeating units of the perfluoropolyether block represented by the above formula (2) include the following repeating units.

[0107] -CF2O-

[0108] -CF2CF2O-

[0109] -CF2CF2CF2O-

[0110] -CF(CF3)CF2O-

[0111] -CF2CF2CF2CF2O-

[0112] -C(CF3)2O-

[0113] In the formula (2), a perfluoropolyether block of the following formula (10) in which z=1 and x and y are 0 is preferred because of its excellent compatibility with the organopolysiloxane.

[0114] -CF2(OCF2) v (OC2F4) w OCF2- (10)

[0115] (In the formula, v and w are numbers of 0 to 200, preferably 0 to 50, respectively, but v+w=3 to 200, preferably v+w=10 to 50. The repeating unit of (OC2F4) may be a straight chain or a branched chain, and the repeating units may be randomly bonded to each other.)

[0116] The perfluoropolyether blocks represented by the above formulae are generally distributed blocks in the structure, and v, w, x and y are average values ​​per molecule.

[0117] In the formula (1), Q is characterized in that it is a divalent linking group optionally containing at least one of an oxygen atom and a nitrogen atom, and preferably has 2 to 12 carbon atoms. Examples of the group containing an oxygen atom include an ether group or an ester group, and examples of the group containing a nitrogen atom include an amino group or an amide group.

[0118] Examples of Q include the following groups.

[0119]

[0120] Among them, -CH2OCH2CH2CH2- is preferred from the viewpoint of easy connection between the organopolysiloxane block and the perfluoropolyether block.

[0121] The number average molecular weight of the organohydrogenpolysiloxane of formula (1) is preferably 2000 to 500000. When the number average molecular weight is within this range, the solubility of the organopolysiloxane is excellent and it is also easy to handle. It should be noted that in the present invention, the number average molecular weight is a polystyrene conversion value obtained by GPC (gel permeation chromatography) measurement using toluene as an elution solvent (the same applies hereinafter).

[0122] [Measurement conditions]

[0123] Elution solvent: toluene

[0124] Flow rate: 0.6mL / min

[0125] Detector: Differential Refractive Index Detector (RI)

[0126] Column: TSK Guardcolumn SuperH-H

[0127] TSKgel SuperH5000(6.0mmI.D.×15×1)

[0128] TSKgel SuperH4000(6.0mmI.D.×15×1)

[0129] TSKgel SuperH3000(6.0mmI.D.×15×1)

[0130] TSKgel SuperH2000(6.0mmI.D.×15×1)

[0131] (All manufactured by Tosoh Corporation of Japan)

[0132] Column temperature: 40°C

[0133] Sample injection volume: 50 μL (toluene solution with a concentration of 0.3 mass %)

[0134] In the above formula (1), g is a number greater than or equal to 0, but the number average molecular weight of the organohydrogenpolysiloxane of formula (1) is preferably a number satisfying 2000 to 500000. Specifically, g is preferably a number of 0 to 100, and more preferably a number of 0 to 50.

[0135] The present invention also relates to a method for producing the organohydrogenpolysiloxane having the above-mentioned perfluoropolyether block. The organohydrogenpolysiloxane of the present invention can be produced by the method described below.

[0136] The organohydrogenpolysiloxane represented by the formula (1) can be obtained by mixing (a) a perfluoropolyether-organopolysiloxane block copolymer represented by the formula (11), (b) an organohydrogenpolysiloxane and (c) an acid catalyst and performing an exchange reaction between the siloxanes of (a) and (b).

[0137] (a) The perfluoropolyether-organopolysiloxane block copolymer represented by the formula (11) can be produced by the method described in Japanese Patent No. 4900854 or the like.

[0138] Specifically, at least one of an organohydrogenpolysiloxane having one hydrosilyl group at one end for inducing W4 and an organohydrogenpolysiloxane having one hydrosilyl group at each end for inducing W3 and / or W4, and a compound represented by the following formula (12) having a group Q' having an unsaturated group on both sides of Rf are subjected to hydrosilylation in the presence of a platinum catalyst.

[0139]

[0140] Q′-Rf-Q′ (12)

[0141] In the above formula (11), Rf is a perfluoropolyether block represented by the above formula (2), and e is a number greater than or equal to 0, preferably 0.

[0142] In the above formula (12), Q' is, for example, a group containing an unsaturated group as shown below.

[0143]

[0144] In the above formula (11), W3 are each independently a divalent organopolysiloxane block represented by the following formula (C).

[0145]

[0146] In formula (C), R 1 Each of them is independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, preferably a methyl group or a phenyl group. Each of them is independently a number of 0 to 1000, preferably a number of 0 to 500.

[0147] In the above formula (11), W4 are each independently a monovalent organopolysiloxane block represented by the following formula (D).

[0148]

[0149] In formula (D), R 1 Each of R is independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, preferably a methyl group or a phenyl group. 2Each independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms and having no aliphatic unsaturated bond or a hydrogen atom, preferably a methyl group and an n-butyl group or a hydrogen atom, more preferably a methyl group or an n-butyl group. Each independently represents a number of 0 to 1000, preferably a number of 0 to 500.

[0150] In the above formula (11), examples of the organohydrogenpolysiloxane having one hydrosilyl group at one terminal for inducing W4 include the following siloxanes, but are not limited to the following formula.

[0151]

[0152] (In the formula, the arrangement of each repeating unit is not limited and may be random or block.)

[0153] In the above formula (11), examples of the organohydrogenpolysiloxane having one hydrosilyl group at each of both terminals for inducing W3 and / or W4 include the following siloxanes, but are not limited to the following formulas.

[0154]

[0155] (In the formula, the arrangement of each repeating unit is not limited and may be random or block.)

[0156] The (b) organohydrogenpolysiloxane may be linear, branched, or cyclic, and examples thereof include the following siloxanes.

[0157]

[0158] Among them, 1,3,5,7-tetramethylcyclotetrasiloxane and 1,3,5,7,9-pentamethylcyclopentasiloxane are preferred.

[0159] The (c) acid catalyst is not particularly limited as long as it is a catalyst that can hydrolyze the siloxane bonds of (a) and (b), but is preferably sulfuric acid, methanesulfonic acid, trifluoromethanesulfonic acid, or the like.

[0160] In the method for producing the organohydrogenpolysiloxane of the formula (1), an organopolysiloxane (d) not having an organohydrogensiloxy unit may be added as needed to carry out an exchange reaction between siloxanes. By adding (d) and reacting them, the content of the organohydrogensiloxy unit in the formula (1) can be controlled, and the mechanical properties of the cured product obtained by hydrosilylation with the organopolysiloxane having an alkenyl group can be easily controlled.

[0161] Examples of the (d) organopolysiloxane having no organohydrogensiloxy unit include cyclic siloxane represented by the following formula (13) and linear siloxane represented by the following formula (14).

[0162]

[0163] (In formula (13), R 1 Each is independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, preferably a methyl group or a phenyl group. m is a number of 3 to 10, preferably a number of 4 to 8.

[0164]

[0165] (In formula (14), R 1 Each of R is independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, preferably a methyl group or a phenyl group. 3 Each is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms and having no aliphatic unsaturated bond, preferably a methyl group. n is a number from 0 to 5000, preferably a number from 2 to 1000.

[0166] Among them, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane are preferred.

[0167] In the method for producing the organohydrogenpolysiloxane of formula (1), (e) an organic solvent may be added arbitrarily to carry out an exchange reaction between siloxanes. Although this reaction can be carried out even in the absence of a solvent, by adding an organic solvent, (a) the perfluoropolyether-organopolysiloxane block copolymer becomes easily compatible with (b) siloxane and (d) polysiloxane, thereby enabling an exchange reaction between siloxanes to be carried out effectively.

[0168] The (e) organic solvent may include, for example, aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as pentane, hexane and heptane; ketones such as methyl ethyl ketone and diisopropyl ketone; alcohols such as 1-propanol, 2-propanol and 1-butanol; fluorinated aromatic hydrocarbons such as (trifluoromethyl)benzene and 1,3-bis(trifluoromethyl)benzene, etc., preferably 1,3-bis(trifluoromethyl)benzene having good compatibility with (a) the perfluoropolyether-organopolysiloxane block copolymer represented by the above formula (11), (b) siloxane and (d) siloxane.

[0169] The organohydrogenpolysiloxane of the formula (1) obtained by the production method is generally an organohydrogenpolysiloxane having a distribution in the structure. In the formula (1), g is an average value per molecule.

[0170] [Example]

[0171] The following examples and comparative examples are shown to specifically illustrate the present invention, but the present invention is not limited to the following examples. It should be noted that in the following examples, the number average molecular weight is a polystyrene conversion value obtained by GPC measurement based on the measurement conditions described above. In addition, in the following examples, the number of repeating units g is 29 The Si-NMR spectrum is composed of Si (R 2 )3-O-structured Si integral value M and -Q-Si(R 1 ) The value calculated from the integral value M' of Si with 2-O- structure is g=(M' / M)-1.

[0172] [Example 1] Synthesis of organohydrogenpolysiloxane (1-1)

[0173] 12.6 g of a perfluoropolyether-organopolysiloxane block copolymer represented by the following formula (11-1) synthesized according to Japanese Patent No. 4900854, 1 g of 1,3,5,7-tetramethylcyclotetrasiloxane and 14 g of 1,3-bis(trifluoromethyl)benzene were added to a reaction vessel, stirred at 25°C for 5 minutes, 37 mg of trifluoromethanesulfonic acid was added, and the mixture was stirred at 25°C for 18 hours. Next, 280 mg of KYOWAAD 500 (manufactured by Kyowa Chemical Industry Co., Ltd.) was added as an adsorbent for the purpose of neutralizing the trifluoromethanesulfonic acid, and the mixture was stirred at 25°C for 2 hours. The obtained mixture was filtered, and 1,3-bis(trifluoromethyl)benzene as a solvent and the generated low molecular weight siloxane were distilled off under reduced pressure to obtain 11.1 g of a white translucent liquid product.

[0174]

[0175] Rf:-CF2(OC2F4) p (OCF2) q OCF2-

[0176] (In the formula, p / q is 1.2 and p+q is 19.)

[0177] The obtained organohydrogenpolysiloxane 1 The H-NMR signals are as follows.

[0178] 1 H-NMR (CDCl3, 400MHz): δppm 0.07 (153H, m), 0.54 (9H, m), 0.89 (6H, t, J = 6.8Hz), 1.32 (8H, m), 1.62 (5H, m), 3.55 (5H, m), 3.77 (5H, m), 4.69 (4H, s).

[0179] The above results show that the obtained organohydrogenpolysiloxane has a structure represented by the following formula (1-1), and the siloxane content in the molecule is 52%. In addition, the number average molecular weight measured by GPC in terms of polystyrene is 3,300.

[0180]

[0181] (In the formula, g is 0.25.)

[0182] Rf: -CF2(OC2F4) p (OCF2) q OCF2-

[0183] (In the formula, p / g is 1.2 and p+q is 19.)

[0184] W1:

[0185] W2:

[0186] (In the above formula (1-1), the number of the organohydrogensiloxy units is 4, the number of the dimethylsiloxy units is 19, and h, i, j, and k in the above w1 and w2 are numbers satisfying these conditions.)

[0187] Q: -CH2OCH2CH2CH2-

[0188] (In the above formula, Rf is bonded to the methylene side of Q (the same applies hereinafter).)

[0189] [Example 2] Synthesis of organohydrogenpolysiloxane (1-2)

[0190] 9.9 g of a perfluoropolyether-organopolysiloxane block copolymer represented by the following formula (11-2), 1.2 g of 1,3,5,7-tetramethylcyclotetrasiloxane, 3.0 g of octamethylcyclotetrasiloxane and 14 g of 1,3-bis(trifluoromethyl)benzene were added to a reaction vessel, stirred at 25° C. for 5 minutes, 37 mg of trifluoromethanesulfonic acid was added, and the mixture was stirred at 25° C. for 18 hours. Next, 280 mg of KYOWAAD 500 (manufactured by Kyowa Chemical Industry Co., Ltd.) was added as an adsorbent for the purpose of neutralizing the trifluoromethanesulfonic acid, and the mixture was stirred at 25° C. for 2 hours. The obtained mixture was filtered, and 1,3-bis(trifluoromethyl)benzene as a solvent and the generated low molecular weight siloxane were distilled off under reduced pressure to obtain 11.0 g of a white translucent liquid product.

[0191]

[0192] Rf: -CF2(OC2F4) p (OCF2)q OCF2-

[0193] (In the formula, p / q is 1.2 and p+q is 19.)

[0194] The obtained organohydrogenpolysiloxane 1 The H-NMR signals are as follows.

[0195] 1 H-NMR (CDCl3, 400MHz): δppm 0.07 (90H, m), 0.54 (4H, m), 1.62 (4H, m), 3.55 (4H, m), 3.77 (4H, m), 4.69 (6H, s).

[0196] The above results show that the obtained organohydrogenpolysiloxane has a structure represented by the following formula (1-2) and a siloxane content in the molecule of 35%. In addition, the number average molecular weight in terms of polystyrene measured by GPC was 3,000.

[0197]

[0198] (In the formula, g is 0.08.)

[0199] Bf: -CF2(OC2F4) p (OCF2) q OCF2-

[0200] (In the formula, p / q is 1.2 and p+q is 19.)

[0201] W1:

[0202] W2:

[0203] (In the above formula (1-2), the number of organohydrogensiloxy units and the number of dimethylsiloxy units contained at the molecular chain end are 6 and 8, respectively, with respect to one perfluoropolyether block represented by Rf, and h, i, j and k in the above w1 and w2 are numbers satisfying these conditions.)

[0204] Q: -CH2OCH2CH2CH2-

[0205] Comparative Example 1 (Siloxane content in the molecule: 20%)

[0206]

[0207] Rf: -CF2(OC2F4) p (OCF2) q OCF2-

[0208] (In the formula, p / q is 1.2 and p+q is 19.)

[0209] Comparative Example 2 (Siloxane content in the molecule: 36%)

[0210]

[0211] Rf′:

[0212] (In the above formula, the arrangement of each repeating unit is random.)

[0213] Table 1 shows the results of the following solubility evaluations conducted on the organohydrogenpolysiloxanes of the above Examples and Comparative Examples.

[0214] [Evaluation of Solubility of Organohydrogen Polysiloxane Having Perfluoropolyether Block in Organopolysiloxane]

[0215] 1 g of the organohydrogenpolysiloxane obtained in the above manner was added to 10 g of α,ω-divinylpolysiloxane of the following formula (g-1), and the mixture was sufficiently stirred. The mixed liquid was visually observed and the solubility was evaluated according to the following criteria.

[0216] Evaluation Criteria

[0217] Classification 0: The mixed liquid separated into two phases.

[0218] Category 1: The mixed liquid is white, translucent and uniform.

[0219] Category 2: The mixed liquid is colorless, transparent and uniform.

[0220]

[0221] [Table 1]

[0222] Example 1 Example 2 Comparative Example 1 Comparative Example 2 Evaluation of solubility 2 1 0 0

[0223] [Preparation of silicone elastomer composition]

[0224] Using the organohydrogenpolysiloxane obtained in the above Examples or Comparative Examples, a silicone elastomer composition was prepared.

[0225] As shown in Table 2, components (f) to (h) and 1,1-dimethylpropoxytrimethylsilane as a reaction control agent were mixed to obtain a composition. It should be noted that in Table 2, the units of the amounts of the composition components are parts by mass, and H / Vi represents the molar ratio of the hydrosilyl group in the composition to the alkenyl group in the composition.

[0226] [Formation of Silicone Elastomer]

[0227] The above compositions were respectively placed into a mold frame of 15 cm × 20 cm × 2 mm. After the composition was fully degassed, the template was placed and clamped, and heated at 120°C for 2 hours to cross-link (f) organohydrogenpolysiloxane and (g) vinylpolysiloxane through a hydrogenation silylation reaction, thereby obtaining a sheet-like silicone elastomer.

[0228] [Evaluation of Transparency of Silicone Elastomer]

[0229] The results of visual observation of the silicone elastomer obtained by the above method are shown in Table 2. In Table 2, "A" indicates a transparent state, "B" indicates a turbid state when the angle of irradiation light is changed, and "C" indicates a state with partial unevenness or partial turbidity.

[0230] [Table 2]

[0231]

[0232] As can be seen from the results in Tables 1 and 2, the organohydrogenpolysiloxane having a perfluoropolyether block of the present invention has excellent solubility in organopolysiloxane, as compared with the same organohydrogenpolysiloxane having a small siloxane content in the related art or the organohydrogenpolysiloxane having a perfluoropolyether group randomly in the side chain, and the organohydrogenpolysiloxane having a perfluoropolyether block of the present invention has excellent transparency, and the silicone elastomer obtained by reacting and curing them is also excellent.

Claims

1. An organohydrogenpolysiloxane having a perfluoropolyether block and represented by the following formula (1), wherein the number average molecular weight is 2,000 to 500,000, and the organopolysiloxane content in one molecule is 35% or more and 99% or less by mass, In formula (1), Rf is a perfluoropolyether block represented by the following formula (10), -CF2(OCF2) v (OC2F4) w OCF2- (10) In formula (10), v and w are numbers of 0 to 200, respectively, but v+w=3 to 200, the repeating unit of (OC2F4) is a straight chain or a branched chain, and the arrangement of each repeating unit is not limited, and is random or block. W1 are each independently a divalent organopolysiloxane block represented by the following formula (A), In formula (A), R 1 are independently an alkyl group or a phenyl group having 1 to 4 carbon atoms, h and i are independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block. W2 are each independently a monovalent organopolysiloxane block represented by the following formula (B), In formula (B), R 1 are independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, R 2 are each independently an unsubstituted or substituted monovalent hydrocarbon group or a hydrogen atom having 1 to 18 carbon atoms and having no aliphatic unsaturated bond, j and k are each independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block, However, the number i of the hydrogen siloxane units of formula (A) and the number k of the hydrogen siloxane units of formula (B) cannot be 0 at the same time. Q is a divalent linking group which may contain at least one of an oxygen atom and a nitrogen atom. In the above formula (1), Q is bonded to any one of the terminal carbon atom of Rf, the terminal silicon atom of W1, or the terminal silicon atom of W2. g is a number greater than or equal to 0.

2. The organohydrogenpolysiloxane having a perfluoropolyether block according to claim 1, The content of the organopolysiloxane in one molecule is 50% or more and 90% or less by mass.

3. A method for producing an organohydrogenpolysiloxane having a perfluoropolyether block represented by formula (1), It has a mixture of (a) a perfluoropolyether-organopolysiloxane block copolymer represented by the following formula (11), (b) organohydrogenpolysiloxane and (c) an acid catalyst to carry out an exchange reaction between the siloxanes of (a) and (b), In formula (11), Rf is a perfluoropolyether block represented by the following formula (10), -CF2(OCF2) v (OC2F4) w OCF2- (10) In formula (10), v and w are numbers of 0 to 200, respectively, but v+w=3 to 200, the repeating unit of (OC2F4) is a straight chain or a branched chain, and the arrangement of each repeating unit is not limited, and is random or block. W3 are each independently a divalent organopolysiloxane block represented by the following formula (C), In formula (C), R 1 are each independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, and c is each independently a number from 0 to 1000, W4 are each independently a monovalent organopolysiloxane block represented by the following formula (D), In formula (D), R 1 are independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, R 2 are each independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 18 carbon atoms or a hydrogen atom without an aliphatic unsaturated bond, and d is each independently a number from 0 to 1000, Q is a divalent linking group which may contain at least one of an oxygen atom and a nitrogen atom, and in the above formula (11), Q is bonded to any one of the terminal carbon atom of Rf, the terminal silicon atom of W3, or the terminal silicon atom of W4, e is a number greater than 0, In formula (1), Rf is a perfluoropolyether block represented by the following general formula (10): -CF2(OCF2) v (OC2F4) w OCF2- (10) In formula (10), v and w are numbers of 0 to 200, respectively, but v+w=3 to 200, the repeating unit of (OC2F4) is a straight chain or a branched chain, and the arrangement of each repeating unit is not limited, and is random or block. W1 are each independently a divalent organopolysiloxane block represented by the following formula (A), In formula (A), R 1 are independently an alkyl group or a phenyl group having 1 to 4 carbon atoms, h and i are independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block. W2 are each independently a monovalent organopolysiloxane block represented by the following formula (B), In formula (B), R 1 are independently an alkyl group having 1 to 4 carbon atoms or a phenyl group, R 2 are each independently an unsubstituted or substituted monovalent hydrocarbon group or a hydrogen atom having 1 to 18 carbon atoms and having no aliphatic unsaturated bond, j and k are each independently a number from 0 to 1000, and the arrangement of each repeating unit is not limited and may be random or block, However, the number i of the hydrogen siloxane units of formula (A) and the number k of the hydrogen siloxane units of formula (B) cannot be 0 at the same time. Q is a divalent linking group which may contain at least one of an oxygen atom and a nitrogen atom. In the above formula (1), Q is bonded to any one of the terminal carbon atom of Rf, the terminal silicon atom of W1, or the terminal silicon atom of W2. g is a number greater than or equal to 0.

4. The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block according to claim 3, wherein: The component (b) is at least one selected from 1,3,5,7-tetramethylcyclotetrasiloxane and 1,3,5,7,9-pentamethylcyclopentasiloxane.

5. The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block according to claim 3 or 4, In formula (11), e is 0.

6. The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block according to claim 3 or 4, The present invention relates to a production method in which (d) an organopolysiloxane having no organohydrogensiloxy unit is further added to the components (a), (b) and (c) in the exchange reaction step, wherein the exchange reaction step is a step of performing an exchange reaction between the siloxanes (a), (b) and (d).

7. The method for producing an organohydrogenpolysiloxane having a perfluoropolyether block according to claim 3 or 4, wherein: (c) The acid catalyst is at least one selected from sulfuric acid, methanesulfonic acid and trifluoromethanesulfonic acid.

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