JPH05105765A - Silicon-based polymer - Google Patents

Abstract

PURPOSE:To obtain the subject polymer with its one end specified as reactive alkenyl group by hydrosilylating reaction of a specific silicon compound with an alkenyl group-contg. compound. CONSTITUTION:The objective polymer suitable as a lightweight and high- toughness structural material is obtained by hydrosilylating reaction of (A) a silicon compound having, in one molecule, combination of at least two SiH groups and at least one alkenyl group such as of the formula (R<1> is methyl, etc.; R<2> is H) with (B) a compound having at least one alkenyl group in one molecule such as vinyl monomer in the presence of a catalyst such as chloroplatinic acid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicon-based polymer having one end regulated by a reactive alkenyl group and a method for producing the same.

[0002]

2. Description of the Related Art At present, various types of silicon materials have been synthesized according to their characteristics and required performance. Polysilane, polycarbosilane, polysiloxane, and polysilazane are the main skeletons of silicon-based materials, but polycarbosilane is only used as a precursor of silicon carbide ceramics for practical use,
The fact is that its structure has not been clearly identified. Therefore, almost no synthesis of polycarbosilane having various structures has been performed.

In the synthetic method using the hydrosilylation reaction,
Conventionally, only a polymer having a low molecular weight has been obtained, and the terminal control has not been performed.

[0004]

DISCLOSURE OF THE INVENTION As a result of intensive studies in view of the above circumstances, the present invention solves these problems and provides a silicon-based polymer whose one end is regulated by a reactive alkenyl group and a method for producing the same. Is. That is, the present invention provides (A) 1
A silicon compound having at least two or more SiH groups in the molecule and at least one or more alkenyl groups in one molecule; (B) a compound having at least one or more alkenyl groups in one molecule; It is a silicon-based polymer having a reactive alkenyl group at one end synthesized by a hydrosilylation reaction.

The reactive silicon polymer synthesized in the present invention is not particularly limited in the main chain skeleton, and various kinds can be synthesized. Moreover, one end is regulated by an alkenyl group. The reactive silicon-based polymer synthesized in the present invention is
The component (A) and the component (B) are synthesized by using a hydrosilylation reaction. In one molecule of the polymer to be synthesized, there is only one unit derived from the component (B) at the terminal, and all other units are derived from the unit (A). Each component may be used alone or in combination of two or more. The ω-alkenylhydrosilane represented by the formula (1) or (2) is preferable as the monomer used as the component (A). (B)
The monomer used as a component is preferably a vinyl monomer represented by the formula (3).

[0006] _{^{HSiR 1 2 -A-CR 2 =}} CH 2 (1) HSiR 1 2 CR 2 = CH 2 (2) BCR 3 = CH 2 (3) R 1 is a monovalent from 1 to 20 carbon atoms The organic groups may be the same or different, and may contain a functional group.

R ¹ is, for example, a methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, isoamyl, n-octyl, n-nonyl or phenyl group. Only one of them may be used, or two or more of them may be used in combination. A is a divalent organic group having 1 to 50 carbon atoms or an oxygen atom, which may contain a functional group.

As a specific example of A, in addition to the alkylene group represented by (CH ₂ ) _n , the structure represented by the following chemical formula 1 can be mentioned.

[0009]

[Chemical 1] A is preferably represented by the following chemical formula 2.

[0010]

[Chemical 2] R ² and R ³ are H or a monovalent organic group having 1 to 10 carbon atoms or a monovalent functional group, which may be the same or different, and the organic group contains a functional group. Good.
Specific examples of R ² and R ³ include H, methyl, ethyl, phenyl, methoxy, ethoxy group, chloro group, acetyl group, cyano group and the like.

B is a monovalent organic group having 1 to 20 carbon atoms or a functional group, and the organic group may contain a functional group. B is, for example, CH ₂ (CH ₂ )
_In addition to the alkyl group represented by _n , the structures shown in Chemical formulas 3 and 4 below are also included.

[0012]

[Chemical 3]

[0013]

[Chemical 4] In the structural formula, Me represents a methyl group and Et represents an ethyl group.
B is preferably as shown in Chemical formula 5. Therefore, the structure of the reactive silicon polymer synthesized is represented by the formula (4) or (5). R ¹ , R ² , R ³ , A and B are the same as above. _{^{BCHR 3 CH 2 (SiR 1 2}} -A-CHR 2 CH 2) n CR 2 = CH 2 (4) BCHR 3 CH 2 (SiR 1 2 -CHR 2 CH 2) n CR 2 = CH 2 (5) polymerization process Uses a large excess of components (A) and (B) and a catalyst, but a solvent may or may not be used. As a mixing method, it is preferable to drop the component (A) after mixing the component (B) and the catalyst so that a mild exothermic reaction is maintained. The reaction temperature is preferably -50 ° C to 150 ° C, more preferably 0 ° C to 100 ° C.

The reaction rate of the polymerization can be controlled by using various catalysts. The type of catalyst that promotes the reaction varies slightly depending on the combination of the monomers, but as the catalyst used for the so-called hydrosilylation reaction, solid platinum is supported on a simple substance of platinum, alumina, silica, carbon black or the like. Compounds, chloroplatinic acid, complexes of chloroplatinic acid with alcohols, aldehydes, ketones, etc., platinum-olefin complexes (for example, Pt (CH ₂ ═C
_{H 2) 2 (PPh 3)} 2 Pt (CH 2 = CH 2) 2 Cl
₂ ); platinum-vinyl siloxane complex (for example, Pt _n
(ViMe ₂ SiOSiMe ₂ Vi) _m , Pt [(Me
ViSiO) ₄ ] _m ), platinum-phosphine complex (for example, Pt (PPh ₃ ) ₄ , Pt (PBu) ₄ ), platinum-
Phosphite complex (for example, Pt [P (OPh) ₃ ])
₄ ) (wherein Me is a methyl group, Bu is a butyl group, Vi is a vinyl group, Ph is a phenyl group, and m and n are integers), dicarbonyldichloroplatinum, and Ashby's US Patent Nos. 3159601 and 3
Also included are the platinum-hydrocarbon complexes described in 159662, as well as the platinum alcoholate catalysts described in Lamoreaux US Pat. No. 3,209,972. In addition, Modic (Mo
The platinum chloride-olefin composites described in U.S. Pat. No. 3,516,964 to Dic) are also useful in the present invention. Further, as an example of the catalyst other than the platinum compound, R
hCl (PPh ₃ ) ₃ , RhCl ₃ , RhAl ₂ O ₃ ,
RuCl ₃ , IrCl ₃ , FeCl ₃ , AlCl ₃ , P
Examples thereof include dCl ₂ 2H ₂ O, NiCl ₂ and TiCl ₄ . These catalysts may be used alone or in combination of two or more. From the viewpoint of catalytic activity, chloroplatinic acid, a platinum-olefin complex and a platinum-vinylsiloxane complex are preferable. The amount of the catalyst is not particularly limited, but it is preferably used in the range of 10 ^-1 to 10 ^-8 mol with respect to 1 mol of the hydrosilyl group of the formula (1) or the formula (2).

Specific examples of the solvent used for the polymerization include hydrocarbon solvents such as benzene and toluene, ether solvents such as tetrahydrofuran and 1,4-dioxane, chloroform, methylene chloride and 1,2-. A halogen-based solvent such as dichloroethane can be preferably used. Further, the amount is preferably 0 to 5 L per 1 mol of the total amount of the monomers.

The reactive silicon polymer thus synthesized preferably has an average molecular weight of 1,000 to 50,000. Terminal alkenyl functional group ratio is 90-100% of one end
Is preferable, and 95-100% is more preferable.

[0017]

The present invention will be specifically described below with reference to examples, but the contents of the present invention are not limited thereto. Production Example 1 10.4 μL (2 × 10 ⁻³ mmo) of a mixed solution of 0.84 g (0.01 mol) of 1-hexene, 10 wt% of chloroplatinic acid catalyst, dimethoxyethane, and isopropanol (9: 1)
l, 1 × 10 ⁻⁵ mol per 1 mol of SiH) was dissolved in 10 mL of dry chloroform to prepare a solution of HMe ₂ SiC.
A solution prepared by dissolving 22.04 g (0.22 mol) of H ₂ CH = CH _{2 in} 10 mL of dry chloroform was slowly added dropwise at room temperature under a nitrogen atmosphere. The dropping rate was adjusted so that a mild exothermic reaction was maintained during the dropping. After the dropping was completed, the reaction solution was stirred for 1 day at room temperature. The platinum catalyst used was removed by passing the reaction solution through a silica gel column. When the volatile components were evaporated, a crude polymer having an olefin terminal was obtained. The crude polymer was purified by reprecipitation from methylene chloride / methanol, dried under reduced pressure, and then about 16.0 g of an olefin-terminated polycarbosilane polymer having the following structural formula.
(About 70% yield) was obtained. The number average molecular weight measured by GPC was 1,600, and the weight average molecular weight was 3,400. The terminal alkenyl functional group ratio is the number average molecular weight and ¹ H-NMR.
It was 95% with respect to one end calculated from the integral value of.

CH ₃ (CH ₂ ) ₃ (CH ₂ CH ₂ SiMe ₂ CH ₂ ) _n CH = CH ₂

[0019]

INDUSTRIAL APPLICABILITY According to the present invention, the silicon-based polymer provided at one end with a reactive alkenyl group is used,
Lightweight and tough structural materials can be manufactured.

[Chemical 5]

Claims (1)

[Claims] 1. (A) At least two S or more in one molecule
Silicon compound having iH group and at least one or more alkenyl groups in one molecule, (B) Compound having at least one or more alkenyl groups in one molecule, piece synthesized by hydrosilylation reaction of both components A silicon-based polymer having a reactive alkenyl group at the terminal.