JP3353608B2 - Method for producing polysilane-polysiloxane copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a novel polysilane-polysiloxane copolymer containing an organic polysilane in an organic polysiloxane.

[0002]

2. Description of the Related Art
As a method for obtaining a crosslinked product of polysiloxane, a method of condensing silanol, an aminooxy group which is easily hydrolyzed,
A method in which an alkoxy group, an oxime group, or the like is bonded to a siloxane chain and reacted with moisture in the air to cause polycondensation, a compound in which a hydrogen atom is bonded to a silicon atom and a vinyl group or an allyl group, etc. A method in which a compound having an aliphatic unsaturated hydrocarbon group bonded thereto is crosslinked by a hydrosilylation reaction using a Group VIII compound as a catalyst, and a silicon compound having a methacrylate or acrylate group bonded thereto is irradiated with ultraviolet rays or the like. A method of causing photocrosslinking is known.

However, the above-mentioned crosslinking method by polycondensation is slow in the reaction and the initial dimensional stability of the crosslinked product is poor due to the release of the reactive residue out of the system. On the other hand, in a composition in which a reactive residue remains after crosslinking, there is a disadvantage that the hardness becomes higher when the composition is placed in a heating atmosphere. Further, the photocrosslinking method using an acrylate group or the like has a problem that the thermal stability of the reaction site is low, so that when used in a high temperature atmosphere, the stability is low.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a polysilane-polysiloxane copolymer from which a polysiloxane crosslinked product can be obtained without the above-mentioned problems.

[0005]

Means for Solving the Problems and Embodiments of the Invention The present inventors have conducted intensive studies in order to achieve the above object, and as a result, mixed-reacted an aminooxy group-containing organic polysilane and a hydroxyl group-containing organic polysiloxane. In particular, by providing an aminooxy group in excess relative to the hydroxyl group and performing a mixing reaction so that the aminooxy group remains in the obtained copolymer, a polysiloxane crosslinked product effective as a hermetic sealing material or the like is provided. It has been found that a polysilane-polysiloxane copolymer can be obtained. Further, in this case, even if the aminooxy group-containing organic polysilane produced by reacting the SiH group-containing polysilane with the hydroxylamine compound and the hydroxyl group-containing organic polysiloxane are reacted in the presence of the hydroxylamine compound, the polysilane-polysiloxane is similarly reacted. The inventors have found that a siloxane copolymer can be obtained, and have accomplished the present invention.

Now, the present invention will be described in further detail. A method for producing a polysilane-polysiloxane copolymer according to the present invention is characterized in that an aminooxy group-containing organic polysilane and a hydroxyl group-containing organic polysiloxane are mixed and reacted. It is.

Here, the aminooxy group-containing organic polysilane has the general formula (1) obtained by the following method.
Alternatively, the one shown in (2) can be used.

[0008]

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Here, R ^{1 to} R ⁶ represent the same or different unsubstituted or substituted monovalent hydrocarbon groups, Q represents a hydrogen atom,
It represents a halogen atom such as a chlorine atom or a bromine atom, a sulfonic acid residue, or the like.

The monovalent hydrocarbon group of R ^{1 to} R ⁶ preferably has 1 to 20 carbon atoms, particularly 1 to 12 carbon atoms, such as an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group and an aralkyl group. R ¹ of is a part or all of the groups hydrogen atoms can be exemplified been substituted with halogen atoms or a cyano group, as R ^1, R ² can be obtained by reacting a hydroxyl group-containing siloxane, a by-product In consideration of removing R ² NOH, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, and a propyl group is preferable.

Further, x and z are each an integer of 0 or more, y
Is an integer of 1 or more, x + y = 3 to 10,000, especially 5 to 1,000, x + z = 3 to 10,000, particularly 5 to 10
00 is preferably satisfied. That is, the molecular weight of the aminooxy group-containing organic polysilane is not particularly limited, but when only the amount for adjusting the weight to be reduced in the crosslinking reaction is considered, an amount of siloxane corresponding to the functional group lost by crosslinking is generated. It is necessary to comprehensively consider that a silylene bond to be incorporated is incorporated, and a polysilane having a polymerization degree of 3 or more and 10,000 or less, particularly 5 or more and 1
It is preferable to use a polysilane of 000 or less, and if it is in this range, it is also suitable for maintaining the viscosity of the base polymer (block copolymer) to an extent that can be processed.

The polysilane containing a substituent Q of the formula (1a) used to obtain the polysilane of the formula (1) can be produced by various methods, for example, when Q is a hydrogen atom. In this case, a method of polymerizing by Wurtz coupling polymerization using a halogenated organosilane of R ⁵ HSiX ₂ as a component (where X represents a halogen atom such as chlorine or bromine), or a silane containing R ⁵ SiH ₃ Using a metallocene catalyst such as Ti, Zr or Hf as a catalyst (Harrod) et al. (J. Am. Chem. So.
c. 1986, 108, 4059). Further, when Q is an acid residue such as a halogen atom or a sulfonic acid residue, it can be produced by reacting an acid corresponding to a phenyl group-containing polysilane.

The polysilane represented by the above formula (2a) can be prepared by the method described in Japanese Patent Application Laid-Open No. H5-262881, the halogenated terminal polysilane or the method disclosed in Japanese Patent Application Laid-Open No. H6-4921.
No. 9 is exemplified. By reacting these with hydroxyamine, a polysilane of the formula (2) can be obtained.

In these methods for producing aminooxy group-containing polysilane, it is preferable to use polysilane having a hydrogen atom as the substituent Q, since there are few by-products.

Next, as the hydroxyl group-containing organic polysiloxane to be reacted with the aminooxy group-containing polysilane, any siloxane containing a hydroxyl group may be used.
A polysiloxane having a hydroxyl group only at both terminals as represented by the following general formula (3) is particularly preferable for controlling the reaction. HO (R ⁷ R ⁸ SiO) _n H (3)

Here, R ⁷ and R ⁸ are the same or different unsubstituted or substituted monovalent hydrocarbon groups, and examples thereof are the same as those exemplified above for R ^{1 to} R ⁶ . The degree of polymerization n of the polysiloxane is not particularly limited, but is preferably 10 or more and 5000 or less in consideration of the physical strength of the obtained polysilane-polysiloxane copolymer. 5
If it exceeds 000, the compatibility with polysilane becomes poor,
In addition, the reaction tends to be poor, and the viscosity of the reaction product with the polysilane is high, so that the processability may be poor. If it is less than 10, bleeding of the unreacted polysilane component may become a problem.

In the present invention, the ratio at which the aminooxy group-containing organic polysilane and the hydroxyl group-containing organic polysiloxane are mixed and reacted is not particularly limited, but the ratio of the aminooxy group to the hydroxyl group (molar ratio) ) Is 1.
A range of 2 or more, particularly 2 or more and 20 or less is preferable. When the above ratio is less than 1.2, both aminooxy groups and hydroxyl groups are likely to remain, and there is a problem in stability over time.

The mixing reaction between the above-mentioned aminooxy group-containing organic polysilane and the hydroxyl group-containing organic polysiloxane is from 0 to 1
It is preferable to carry out the stirring reaction at 50 ° C., especially at 20 to 50 ° C. for about 2 to 24 hours.

By this mixing, a deamino alcohol reaction occurs as shown by the following formula: R ¹ R ² NO− + HO− → −O− + R ¹ R ² NOH, and the silicon atom at the aminooxy group site of the organic polysilane is The polysilane-polysiloxane copolymer is obtained by bonding a silicon atom at the hydroxyl group of the siloxane via an oxygen atom.

In this case, the aminooxy group-containing polysilane, particularly the aminooxy group side chain polysilane is a hydrogen side chain polysilane (Q in the above formula (1a)
= H) with a hydroxylamine of the formula (4).
By utilizing this reaction, a polysilane-polysiloxane copolymer can be similarly produced by reacting a SiH group-containing polysilane with a hydroxyl group-containing polysiloxane in the presence of a catalytic amount of hydroxylamines.
The reaction conditions in this case can be the same as those described above.

[0021] The polysilane-polysiloxane copolymer thus obtained, when aminooxy groups remain, can be crosslinked by hydrolyzing the remaining aminooxy groups with water in the air. Further, prior to the above-mentioned hydrolysis reaction, the remaining aminooxy group may be reacted with an alcohol to convert it into an alkoxy group, thereby reducing the hydrolyzability.

In addition to the crosslinking reaction by moisture in the air due to the remaining aminooxy group, when the polysilane has a hydrogen atom bonded to a silicon atom (SiH group), the crosslinking may be carried out by a vinyl group or the like. It is also possible to crosslink with a polysiloxane having an aliphatic unsaturated bond by a hydrosilylation reaction.Moreover, when the copolymer has an aliphatic unsaturated bond such as a vinyl group, a hydrogen atom bonded to a silicon atom is replaced with a hydrogen atom. Crosslinking can also be performed by a hydrosilylation reaction using the polysiloxane (organohydrogenpolysiloxane). In addition, when the polysilane portion of the aminooxy group-containing organic polysilane has a cyclic structure, a long-chain structure or a branched structure, it can be cross-linked by ultraviolet irradiation. In this case, when light including ultraviolet rays is irradiated by a low-pressure mercury lamp or the like, the polysilane chain portion is oxidized into siloxane, so that weight loss or deposition loss due to elimination of the remaining aminooxy group or alkoxy group can be prevented. Expected to expand.

[0023]

According to the present invention, the crosslinking can be carried out by the moisture in the air as it is, or the crosslinking can be carried out by the irradiation of ultraviolet rays with a low-pressure mercury lamp. Since the part is oxidized to form a siloxane, a polysilane-polysiloxane copolymer which can prevent weight loss or deposition loss due to elimination of the remaining aminooxy group or alkoxy group and can be expected to have a tendency to expand can be obtained. The copolymer is suitably used as a hermetic sealing material.

[0024]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

Example 1 1.6 g of phenylhydrooligosilane having an average molecular weight of 1100 (degree of polymerization = 10) was dissolved in 30 ml of toluene.
90 mg was added, and the mixture was stirred and reacted at room temperature for 16 hours. Then, 5 g of dimethylsiloxane containing hydroxyl groups at both ends having an average molecular weight of 10,000 (degree of polymerization = 135) was added. Obtained. The solvent was removed from the obtained solution under reduced pressure to obtain a pale yellow rubbery polymer represented by the following formula. The polymer became insoluble in toluene and tetrahydrofuran when left at room temperature for one day.

[0026]

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Example 2 A viscous solution was obtained by reacting phenylhydrooligosilane with diethylhydroxyamine in toluene and then with dimethylsiloxane having a terminal hydroxyl group in the same manner as in Example 1 to obtain 5 g of t-butyl alcohol. The mixture was added and reacted at 110 ° C. for 30 minutes.
The solvent and excess t-butyl alcohol were removed from this solution under reduced pressure to obtain a pale yellow rubbery polymer represented by the following formula. The polymer was a pale yellow viscous liquid of 37500 in terms of polystyrene by GPC, which was soluble in toluene even after standing at room temperature for one week.

[0028]

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Example 3 1.6 g of phenylhydrooligosilane having an average molecular weight of 1100 (degree of polymerization = 10) was dissolved in 30 ml of toluene, and dimethylsiloxane containing hydroxyl groups at both ends having an average molecular weight of 10,000 (degree of polymerization = 13).
5) was added and dissolved uniformly. To this solution was added 100 mg of diethylhydroxyamine at room temperature, and 2
After stirring and reacting for 4 hours, the solvent was removed under reduced pressure to obtain a pale yellow rubbery polymer represented by the following formula.

[0030]

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────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-302035 (JP, A) JP-A-4-366170 (JP, A) JP-A-9-241384 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C08L 83/04 C08K 5/54 C08G 77 / 44,77 / 60

Claims (4)

(57) [Claims] 1. A method for producing a polysilane-polysiloxane copolymer, comprising mixing and reacting an aminooxy group-containing organic polysilane with a hydroxyl group-containing organic polysiloxane. 2. The method according to claim 1, wherein the aminooxy group-containing organic polysilane is reacted with the hydroxyl group-containing organic polysiloxane such that the molar ratio of the aminooxy group to the hydroxyl group is 1.2: 1 or more. . 3. An aminooxy group-containing organic polysilane,
The following general formula (1) or (2) (R ³ R ⁴ Si) _x (R ⁵ (R ¹ R ² NO) Si) _y (1) R ¹ R ² NO (R ³ R ⁴ Si) _x (R ⁵ R ⁶ Si) _z ONR ¹ R ² (2) (wherein, R ^{1 to} R ⁶ are the same or different, unsubstituted or substituted monovalent hydrocarbon groups, x and z are integers of 0 or more, and y is X and y are x + y = 3 to 10,000, x
+ Z = integer satisfying 3 to 10,000. Wherein the hydroxyl-containing organopolysiloxane is represented by the following general formula (3): HO (R ⁷ R ⁸ SiO) _n H (3) (wherein R ⁷ and R ⁸ are the same or different and are unsubstituted) Or a substituted monovalent hydrocarbon group, and n is an integer of 10 to 5000.) The production method according to claim 1 or 2, wherein 4. A polysilane comprising reacting an aminooxy group-containing organic polysilane produced by reacting a SiH group-containing polysilane with a hydroxylamine compound and a hydroxyl group-containing organic polysiloxane in the presence of the hydroxylamine compound. A method for producing a polysiloxane copolymer.