JPH04247091A - Organic silicon compound - Google Patents

Abstract

PURPOSE:To provide a new organic silicon compound having the photolysis- preventing effect of hindered amine and the oxidation-preventing action of hindered phenol, capable of stably keeping the above activities and useful as a stabilizer for organic polymer. CONSTITUTION:The compound of formula I {R<1> and R<2> are alkyl, phenyl, etc. ; R<3> is group of formula II [(r) is 0 or 1; R<5> is H, methyl, etc.; Z is O or N-R<7> (R<7> is alkyl); R<6> is alkylene]; R<4> is group of formula III (R<8> is alkylene; t-Bu is tert. butyl); X is (R<1>)-Si-; m>=n; (n) and (p) are >=1}, e.g. the compound of formula IV. The compound can be produced by reacting a polyalkyl hydrogen siloxane compound of formula V ((q) is (n+p), an unsaturated piperidine compound of formula VI and an unsaturated phenol compound of formula VII (R<10> is alkylene), preferably in the presence of a Pt group metal catalyst such as H2PtCl6. The reaction is preferably carried out at 20-100 deg.C.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates to novel organosilicon compounds suitable as stabilizers for organic polymers.

0002

BACKGROUND OF THE INVENTION 2,2,6,6-tetramethylpiperidine and 2,6-di-tert-butylphenol are each known as stabilizers for organic polymers. For example, 2,
2,6,6-tetramethylpiperidine or its derivatives are generally called hindered amines, and are known to have the effect of suppressing the deterioration of general-purpose polymers due to light. Furthermore, 2,6-di-t-butylphenol or its derivatives are generally called hindered phenols, and are known to have the effect of suppressing the decomposition of general-purpose polymers by oxygen.

0003

[Problems to be Solved by the Invention] However, the above-mentioned hindered amines do not have an antioxidant effect, and hindered phenols do not have an anti-photodegradation effect. Therefore, each of these alone is insufficient to stabilize the organic polymer, and generally both are used in combination or in combination with other additives.

[0004] In addition, hindered amine light stabilizers and hindered phenols are unstable against heat or oxidation during the processing of organic polymers, or are susceptible to solvents such as water. This has the disadvantage that the stabilizer is eluted due to this. In order to eliminate this drawback, for example, Japanese Patent Laid-Open No. 56-56187 and Japanese Patent Laid-open No. 2
-28218 publication describes 2,2,6 as a light stabilizer.
, 6-tetramethylpiperidine introduced into the molecule has been disclosed. However, although these prior arts have improved the above-mentioned drawbacks of hindered amines to some extent, they do not provide antioxidant effects themselves, and are still unsatisfactory for use alone as stabilizers for organic polymers. be. Further, there is no known polysiloxane in which both hindered amines and hindered phenols are introduced into the molecule.

Therefore, the present invention provides a method in which both hindered amines and hindered phenols are introduced into the molecule.
It is an object of the present invention to provide an organosilicon compound which has an excellent combination of photodegradation prevention action and antioxidant action and which effectively eliminates the above-mentioned drawbacks of hindered amines and hindered phenols.

[0006]

[Means for achieving the object] According to the present invention, the following general formula (1),

[Formula 1] In the formula, R1 and R2 are an alkyl group, a cycloalkyl group, or a phenyl group, and these may be the same or different groups, and R3 is the following general formula (2),

[Formula, r is 0 or 1, R5 is a hydrogen atom, methyl group or benzyl group, Z is -O- or >N-R7 (R7 is an alkyl group), R
6 is an alkylene group], and R4
is the following general formula (3),

[Chemical formula 3] (wherein, R8 represents an alkylene group, and t-B
u represents a tert-butyl group),
X is a group represented by (R1)3-Si-, and 2
X may be bonded to each other to form a cyclic structure as a whole molecule, m is an integer of 0 or more, and n and p are each an integer of 1 or more. A silicon compound is provided.

According to the present invention, the following general formula (4)
,

[Image Omitted] [Image Omitted] In the formula, R1, R2,
A polyalkyl hydrogen siloxane compound represented by the number corresponding to n+p in 1), and the following general formula (5),

[Image Omitted] In the formula, Z, r and R5 represent the general formula (2
), R9 is an alkylene group, and an unsaturated piperidine compound represented by the following general formula (6),

There is provided a method for producing an organosilicon compound according to claim 1, characterized in that the reaction is carried out with an unsaturated phenol compound represented by the following formula, wherein R10 is an alkylene group.

Polyhydrogensiloxane In synthesizing the organosilicon compound of the present invention represented by the above-mentioned general formula (1), the basic siloxane compounds are as follows:
The general formula (4),

A polyalkylhydrogensiloxane represented by the following formula is used.

That is, the organosilicon compound of the present invention is synthesized by an addition reaction between the SiH group in the molecule and the unsaturated group at the end of the molecule of the unsaturated piperidine compound and the unsaturated phenol compound described below.

In the general formula (4), the groups R1 and R2 are an alkyl group, a cycloalkyl group, or a phenyl group, and these may be the same or different groups. The alkyl group may be linear or branched, but is preferably a lower alkyl group having 10 or less carbon atoms, such as a methyl group, ethyl group, propyl group, or butyl group. It is the basis. In addition, examples of cycloalkyl groups include cyclopentyl, cyclohexyl, and cycloheptyl groups having 5 to 5 carbon atoms.
10 is preferred.

The group X is (R1)3 -Si-(
R1 is a group represented by (as described above), and the two Xs present at the ends of the molecule may be bonded to each other, or the molecule as a whole may have a cyclic structure.

Further, m is an integer of 0 or more, and q is a number corresponding to the total number of n and p in the general formula (1). Generally, these numbers are preferably m+q, ie, m+n+p, equal to or less than 50. If the total number exceeds 50, the synthesized organosilicon compound may have problems such as unsatisfactory compatibility with other organic polymers or reduced workability.

[0013] In the present invention, the polyhydrogensiloxane preferably used is represented by the following formula (7):

[C7
] where s is a number from 2 to 50, most preferably on average 6
Alternatively, polymethylhydrogensiloxane represented by 38 can be mentioned.

In the present invention, the unsaturated piperidine compound used to introduce the hindered amine group represented by the general formula (2) into the polyalkyl hydrogen siloxane is represented by the general formula (5), ie,

[C5
2,2,6,6-tetramethylpiperidine having an ethylenically unsaturated group bonded to the 4-position represented by the following formula is used.

In the general formula (5), R5 is a hydrogen atom, a methyl group or a benzyl group, preferably a hydrogen atom. Also, r is a number of 0 or 1, and Z is
It is a divalent group represented by -O- or >N-R7. Here, R7 is an alkyl group, which may be linear or branched, and preferably has 5 or less carbon atoms. In the present invention, particularly preferred examples of Z include -O- and >Nn-C4H9.

Further, R9 is an alkylene group, which may be linear or branched, and preferably has 8 or less carbon atoms.

The most preferably used unsaturated piperidine compounds represented by the above general formula (5) are:
The following formula (8),

It is 4-allyloxy-2,2,6,6-tetramethylpiperidine represented by the following formula.

Unsaturated phenol compound In the present invention, the unsaturated phenol compound used together with the unsaturated piperidine compound has the general formula (6).
), i.e.

It is 2,6-di-t-butylphenol having an unsaturated bond-containing group bonded to the 4-position represented by the following formula. In the general formula (6), t-Bu is a tert-butyl group, and R10 represents an alkylene group. This alkylene group may be either linear or branched, and is particularly preferably an alkylene group having 1 to 8 carbon atoms.

The unsaturated phenol compound represented by the general formula (6) most preferably used is the following formula (9),

It is 4-allyl-2,6-di-t-butylphenol represented by the following formula.

Reaction The reaction of the above-mentioned polyhydrogensiloxane with an unsaturated piperidine compound and an unsaturated phenol compound is as follows:
This is usually carried out by dropping polyhydrogensiloxane into a mixture of an unsaturated piperidine compound and an unsaturated phenol compound while stirring.

[0021] The reaction temperature is generally preferably carried out within the range of 20 to 100°C. In addition, during the reaction, a catalyst known per se used in the hydrosilylation reaction, such as H2 PtCl6, [PtCl2 (PPh3)
2], [PdCl2 (PPh3)2], [
It is desirable to use a platinum group metal catalyst such as RhCl(PPh3)3 (wherein Ph represents a phenyl group). These catalysts are usually used in an amount of 10 to 500 ppm in terms of platinum group metal, based on the total amount of the unsaturated piperidine compound and unsaturated phenol compound. Such a reaction is usually carried out without a solvent, and it is not necessary to use a reaction solvent, but when it is used, an aprotic solvent such as toluene, xylene, or tetrahydrofuran is preferably used. The amount of each reaction component to be used corresponds to the structure of the target organosilicon compound represented by general formula (1), and the unsaturated piperidine compound and the unsaturated phenol compound are combined in real terms, n:p molar ratio. Take it as a percentage.

Hydrosilylation of the organosilicon compound is carried out by carrying out the above-mentioned reaction, and the unsaturated group at the molecular end of the unsaturated piperidine compound and the unsaturated phenol compound is added to the SiH group of the polyhydrogensiloxane, General formula (1)
An organosilicon compound having a molecular structure represented by is obtained. That is, as is clear from the general formula (1), the organosilicon compound of the present invention has a hindered amine group represented by the general formula (2) and a hindered phenol group represented by the general formula (3). Each has a structure bonded to silicon atoms in the molecular chain. As is clear from the addition reaction, R6 in the general formula (2) is an alkylene group having two fewer carbon atoms than R9 in the general formula (5), and R8 in the general formula (3) is General formula (6
It will be understood that this is an alkylene group having two fewer carbon atoms than R10 in ). Suitable organosilicon compounds of the present invention include, but are not limited to, R1 in the general formula (1).
and R2 is a methyl group, and the hindered amine group represented by the general formula (2) is introduced with 4-allyloxy-2,2,6,6-tetramethylpiperidine of the formula (8), Further, it is an organosilicon compound in which the hindered phenol group of the general formula (3) is introduced by 4-allyl-2,6-di-t-butylphenol of the formula (9). Among these, those in which m in the general formula (1) is 0 are particularly preferred.

[0023] Due to the presence of the hindered amine group represented by the general formula (2), the organosilicon compound of the present invention has the following properties:
It has an excellent photostability effect, and also has an excellent antioxidant effect due to the presence of the hindered phenol group represented by the general formula (3). For example, this organosilicon compound is usually added in the range of 0.001 to 1 to 100 parts by weight of the organic polymer.
By adding 0 parts by weight, the photodecomposition and oxidative deterioration of the organic polymer can be effectively suppressed, and the weather resistance of the organic polymer can be significantly improved. There are various examples of such organic polymers, but in particular, when used in olefin polymers such as polyethylene, polypropylene, polybutadiene, polystyrene, etc., and olefin copolymers, the above-mentioned organic polymers The stabilizing effect of silicon compounds is significant.

Furthermore, as mentioned above, hindered amines such as 2,2,6,6-tetramethylpiperidine and 2,
Hindered phenols such as 6-di-t-butylphenol have photodecomposition inhibiting effects and antioxidant effects, respectively. However, quite surprisingly, the organosilicon compound of the present invention exhibits significantly superior optical properties compared to compounds in which either hindered amine or hindered phenol is introduced into polysiloxane alone, or a mixture of these compounds. It has a decomposition inhibiting effect and an antioxidant effect. This is because the aforementioned hindered amine group and hindered phenol group exist in the same molecule, so they exist in very close proximity.
As a result, it is thought that the photodecomposition inhibiting effect and antioxidant effect of each group are synergistically improved.

[0025]

[Example] Example 1 The following formula (10)

Preparation of the compound represented by: 4-allyloxy-2,2,6,6-tetramethylpiperidine 8.9 g (0.045 mol) 4-allyl-2,6-di-t-butylphenol 1
1.1 g (0.045 mol) and 0.13 g of a 4% isopropyl alcohol solution of H2 PtCl6 .6H2 O were mixed with a stirrer, a reflux condenser,
The mixture was placed in a 50 ml flask equipped with a thermometer and a dropping funnel. This is heated to 70 to 80°C, and the following formula (11) is expressed.

Dimethyl hydrogen polysiloxane represented by [Chemical formula 11]
8.9 g (0.017 mol) was added dropwise over 2 hours. After the dropwise addition, the reaction mixture was kept at 70-80°C for another 2 hours.
The temperature was maintained at . Next, 50.0 g of toluene was added to the reaction mixture, and 0.5 g of activated carbon was added and stirred to remove platinic acid as a catalyst. After filtration, toluene was distilled off, and excess raw materials and volatile byproducts were removed by distillation at 120°C under reduced pressure (2 mmHg).
20.5 g of a yellow oily product was obtained. The IR spectrum and NMR were as shown in FIGS. 1 and 2. From this result, it was confirmed that the above product was a compound represented by the above formula (10).

Example 2 The following formula (12)

Preparation of compound represented by [Chemical formula 12]; 4-allyloxy-2,2,6
, 11.8g of 6-tetramethylpiperidine (
0.06 mol) and 4-allyl-2,6-di-t
- The same operation as in Example 1 was carried out except that the amount of butylphenol used was 7.4 g (0.03 mol),
27.9 g of oily product were obtained. The IR spectrum and NMR of this product were as shown in FIGS. 3 and 4. From this result, it was confirmed that the above product was a compound represented by the above formula (12).

Example 3 The following formula (13)

Preparation of compound represented by [Chemical formula 13]; 4-allyloxy-2,2,6
, 6-tetramethylpiperidine used was 5.9g (0
．． 03 mol) and 4-allyl-2,6-di-t-
The same operation as in Example 1 was carried out, except that the amount of butylphenol used was 14.8 g (0.06 mol).
26.6 g of oily product were obtained. The IR spectrum and NMR of this product were as shown in FIGS. 4 and 5. From this result, it was confirmed that the above product was a compound represented by the above formula (13).

Example 4 To 100 parts by weight of polypropylene, 0.3 parts by weight of each of the compounds synthesized in the above example and 0.1 parts by weight of calcium stearate were blended and kneaded to a thickness of 2.
A sheet of mm was prepared. For these sheets, the residual tensile strength after 1000 hours of exposure was measured using a weatherometer. The measurement results are shown in Table 1.

Comparative Example 1 In Example 4, 0.3 parts by weight of the following hindered amine stabilizers and hindered phenol stabilizers (A) to (D) were used instead of the compounds synthesized in Examples 1 to 3. Polypropylene sheets were prepared using the following combinations as shown in Table 1. Hindered amine stabilizer; (A): Compound represented by the following formula (14).

[Chemical formula 14] (B): A compound represented by the following formula (15).

[Chemical formula 15] Hindered phenol stabilizer; (C): A compound represented by the following formula (16).

[Chemical formula 16] (D): A compound represented by the following formula (17).

[Chemical formula 17] Note that the compound (B
) and (D) were synthesized according to Examples 1 to 3 without using a hindered phenol compound or a hindered amine compound, respectively. For each sheet, the residual tensile strength after 1000 hours of exposure was measured in the same manner as in Example 4. The measurement results are shown in Table 1. Further, as a blank, similar measurements were performed on a polypropylene sheet prepared without blending any of the above stabilizer compounds, and the results are shown in Table 1.

[0030]

[0031]

[Effects of the Invention] The organosilicon compound of the present invention has the photodecomposition prevention effect of hindered amine and the antioxidant effect of hindered phenol, and furthermore, this compound is volatilized or extracted and removed with a solvent such as water. Never. Therefore, it becomes possible to significantly improve the weather resistance of organic polymers such as polyolefins. Further, according to the present invention,
In the synthesis of the organosilicon compound mentioned above, by appropriately changing the quantitative ratio of hindered amine and hindered phenol, it is possible to change the balance between the photodegradation prevention effect and the antioxidant effect of the resulting organosilicon compound depending on the purpose. can.

[0032]

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an IR spectrum of the organosilicon compound of the present invention obtained in Example 1.

FIG. 2 is a diagram showing an NMR spectrum of the organosilicon compound of the present invention obtained in Example 1.

FIG. 3 is a diagram showing an IR spectrum of the organosilicon compound of the present invention obtained in Example 2.

FIG. 4 is a diagram showing an NMR spectrum of the organosilicon compound of the present invention obtained in Example 2.

FIG. 5 is a diagram showing an IR spectrum of the organosilicon compound of the present invention obtained in Example 3.

FIG. 6 is a diagram showing an NMR spectrum of the organosilicon compound of the present invention obtained in Example 3.

Claims (3)

[Claims] Claim 1: The following general formula (1), [Image Omitted] In the formula, R1 and R2 are an alkyl group, a cycloalkyl group, or a phenyl group, and these may be the same or different groups, and R3 is the following general formula (2
), [Formula 2] [wherein r is 0 or 1, R5 is a hydrogen atom, a methyl group or a benzyl group, and Z is -O- or >N
-R7 (R7 is an alkyl group) and R6 is an alkylene group], and R4 is the following general formula (3), [Formula 3] (wherein, R8 is an alkylene group). and t-Bu represents a tert-butyl group), and X represents a group represented by (
R1) is a group represented by 3 -Si-, two X's may be bonded to each other to form a cyclic structure as a whole molecule, m is an integer of 0 or more, n and p teeth,
An organosilicon compound, each of which is an integer of 1 or more. [Claim 2] The following general formula (4), [Image Omitted] In the formula, R1, R2, X and m are represented by the general formula (1).
), q is a number corresponding to n+p in the general formula (1), and a polyalkyl hydrogen siloxane compound represented by the following general formula (5)
, [Image Omitted] In the formula, Z, r and R5 are as explained in the above general formula (2), and R9 is an alkylene group. An unsaturated piperidine compound represented by the following general formula ( 6),
The method for producing an organosilicon compound according to claim 1, wherein R10 is an alkylene group. 3. A method for stabilizing an organic polymer, which comprises adding 0.001 to 10 parts by weight of the organosilicon compound according to claim 1 per 100 parts by weight of the organic polymer.