JPS6357644A - Production of dimethylsiloxane block copolymer - Google Patents

Abstract

PURPOSE:To obtain the title block copolymer which can be synthesized over a wide temp. range with less reaction stages by radical polymn., by polymerizing a vinyl monomer in the presence of a specified polydimethylsiloxane compd. as a polymn. initiator. CONSTITUTION:A vinyl monomer is polymerized in the presence of a polydimethysiloxane compd. having diacyl peroxide groups, represented by formula I as a radical polymn. initiator. In the formula, R1 is a 1-15C alkyl or an aryl; R is a 3-10C alkylene or a group of formula II; R2 is a 1-15C alkylene or phenylene; R3 is a 3-10C alkylene or -(CH2)2O(CH2)3- group; m in 10-200; and x is 2-10. Pref. 10-90pts.wt. polydimethylsiloxane compd. is used per 90-10pts.wt. vinyl monomer. The ratio widely varies depending on the use of the copolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing a polymer compound, and particularly to a method for producing a dimethylsiloxane block copolymer.

(Prior Art) Dimethylsiloxane block copolymers have been synthesized by several methods.

For example, J.C.Saam
Macromolecules
s) Vol. 3, page 1 (1970), reports that a styrene-dimethylsiloxane block copolymer was obtained by an anionic polymerization method (hereinafter, this method will be referred to as an anionic polymerization method).

In addition, Ikushi Tezuka et al.

Chew, Rapid Commun,) 5 volumes,
p. 559 (1984) reported that a vinyl acetate-dimethylsiloxane block copolymer was obtained by a coupling reaction of a prepolymer having a functional group (hereinafter, this method is referred to as the prepolymer method). ).

Furthermore, Hiroshi Inoue et al., Proceedings of the Society of Polymer Science, Vol. 34, 293.
(1984) reported that a methyl methacrylate-dimethylsiloxane block copolymer was obtained by radical polymerization using an azo group-containing polysiloxane amide having radical polymerization activity (hereinafter, this method will be applied to an azo group-containing polysiloxane amide). (referred to as the method using siloxane amide)
.

(Problems to be Solved by the Invention) However, conventional synthesis methods have several problems as shown below.

l) In the methods using the anionic polymerization method and prepolymer method, the vinyl monomers that can be used in the reaction are limited, the reaction process is multi-step, and the reaction conditions are difficult to use industrially. Or so.

2) In the method using the azo group-containing polysiloxane amide, the temperature at which the polymer initiator has a half-life of 10 hours is about 6
It is limited to 5°C and is not suitable for use in a wide range of temperatures.

In order to industrially produce a block copolymer, it is necessary to be able to synthesize it using radical polymerization and to be able to synthesize it at a wide range of temperatures from low to high temperatures.

The purpose of the present invention is to solve these problems and provide a method for producing a dimethylsiloxane block copolymer by radical polymerization, which can be applied to many vinyl monomers, requires few reaction steps, and can be synthesized at a wide range of temperatures. There is a particular thing.

(Means for Solving the Problems) The object of the present invention is achieved by the method for producing a dimethylsiloxane block copolymer described below.

The method for producing a dimethylsiloxane block copolymer of the present invention involves radical polymerization of a polydimethylsiloxane compound having a diacyl peroxy group in the molecule represented by the following structural formula (A) in polymerizing a vinyl monomer. This is a method for producing a dimethylsiloxane block copolymer, which is characterized in that it is used as an initiator.

-・・・・・(A) (In the formula, R1 represents an alkyl group or an aryl group having 1 to 15 carbon atoms. Also, R represents an alkylene group having 3 to 1 o carbon atoms or a -RgCORs- group, R2 has 1 to 1 carbon atoms
5 represents an alkylene group or a phenylene group, R5 is an alkylene group having 3 to 10 carbon atoms or -(CHz) to
(CHg)! -Represents a group. Also, m is lO~200
and X is 2 to 10).

The present invention will be explained in more detail below.

The polydimethylsiloxane compound having a diacyl peroxy group in the molecule used in the present invention has the above structural formula (A
). R9 in the formula is an alkyl group having 1 to 15 carbon atoms or a phenyl group.

When the number of carbon atoms is 16 or more, the reactivity becomes poor and synthesis becomes difficult. With respect to R and R1, it is difficult to obtain raw materials and synthesis is difficult under conditions other than those described above. Also, m is 10 to 200
and X is 2 to 1o. When m>200, the molecular weight becomes too large and synthesis is difficult, and when m<10, the dimethylsiloxane component is so small that its properties cannot be expressed.

When X is 11 or more, synthesis becomes difficult.

The compound represented by this structural formula (A) is about 60 to 80°C
It can obtain a half-life of 10 hours at a temperature in the range of , and has radical polymerization properties that allow it to be used as a component of copolymers. Further, this polydimethylsiloxane compound has a solubility equivalent to that of ordinary polydimethylsiloxane, and easily dissolves in benzene, toluene, xylene, hexane, and the like.

Next, examples of vinyl monomers that can be used in the present invention include styrene, methylstyrene, diphenylethylene, ethylstyrene, dimethylstyrene, vinylnaphthalene, vinylphenanthrene, vinylmesitylene, 3.4.6-) dimethylstyrene, 1- Hydrocarbon compounds such as vinyl-2-ethylacetylene, butadiene, isoprene, piperylene; chlorstyrene, methoxystyrene, bromustyrene, cyanostyrene, fluorostyrene, dichlorostyrene, N,N-dimethylaminostyrene, nitrostyrene, chloromethyl Styrene derivatives such as styrene, trifluorostyrene, trifluoromethylstyrene, and aminostyrene; acrylonitrile, metacyclonitrile, α-
7 Cyclonitrile derivatives such as acetoxyacrylonitrile Niacrylic acid, methacrylic acid; Acrylic acid esters such as methyl acrylate, lauryl acrylate, chloromethyl acrylate, ethyl acetoxyacrylate; cyclohexyl methacrylate, dimethylaminoethyl methacrylate, glycidyl methacrylate 1 ．． Methacrylic acid esters such as tetrahydrofurfuryl methacrylate and hydroxyethyl methacrylate; Vinylidene compounds such as vinylitine chloride, vinylidene bromide, and vinylidene cyanide; Acrylamide, methacrylamide, N-butoxymethylacrylamide, N-phenylacrylamide, diacetone acrylamide , N,N-dimethylaminoethyl acrylamide and other acrylamide derivatives; fatty acid vinyl derivatives such as vinyl acetate, vinyl butyrate, and vinyl caprate;
Vinylfuran, 2-vinylbenzofuran, vinylthiophene, vinylimidazole, methylvinymidazole, vinylpyrazole, vinyloxazolidone, vinylthiazole, vinyltetrazole, vinylpyridine, methylvinylpyridine, 2,4-dimethyl-6-vinyltriazine, vinylquinoline There are heterocyclic vinyl compounds such as

The vinyl monomer can be used alone or in combination of two or more types.

Generally, the composition ratio of the polydimethylsiloxane compound having a diacyl type peroxy group in the molecule and the vinyl type monomer is 10 to 90 parts by weight of the polydimethylsiloxane compound having a diacyl type peroxy group in the molecule. The amount is preferably 90 to 10 parts by weight, and the proportion can be selected over a wide range depending on the intended use. When the polydimethylsiloxane compound is less than 10 parts by weight and 9
If the amount is more than 0 parts by weight, the characteristics as a block copolymer cannot be expressed.

Further, as the radical polymerization method, any method such as a solution polymerization method, a bulk polymerization method, an emulsion polymerization method, a Q-turbidity polymerization method, etc. can be performed.

The reaction temperature for radical polymerization is 30 to 120°C, preferably 50 to 100°C. If the reaction temperature is lower than 30°C, the reaction time will be too long, making it industrially unsuitable. Furthermore, if the temperature is higher than 120°C, the peroxy group will instantly decompose and the reaction will not proceed well.

The reaction time is generally 0.5 to 100 hours, preferably 1 to 100 hours.
It is 30 hours. If the reaction time is shorter than 0.5 hours, the reaction will not proceed sufficiently. Moreover, if it is longer than 100 hours, it is industrially inappropriate.

As described above, when the method for producing a dimethylsiloxane block copolymer according to the present invention is used, a dimethylsiloxane block copolymer can be obtained through a -step reaction. Note that the obtained dimethylsiloxane block copolymer contains a homopolymer of vinyl monomers, but by performing reprecipitation or solvent extraction using an appropriate solvent, a highly pure block copolymer can be obtained. can be separated.

(Effects of the Invention) The method for producing a dimethylsiloxane block copolymer according to the present invention can be applied to many vinyl monomers, and the reaction can be carried out in one step over a wide range of temperatures with extremely simple operations. As a result, various dimethylsiloxane-based block copolymers can be produced, and the industrial value is extremely high. Furthermore, the dimethylsiloxane block copolymer obtained by the present invention can be used as a raw material or surface modifier for sealing agents, various plastic films and molded products, fibers, rubber, paints, adhesives, etc.
It can provide the properties of polydimethylsiloxane, such as water resistance, heat resistance, and weather resistance.

(Example) Next, the present invention will be explained with reference to Examples and Comparative Examples.

Example 1 60 parts of a polydimethylsiloxane compound having a diacyl type peroxy group in the molecule represented by the following structural formula (1) with an average molecular l of 10,000 and an active oxygen content of 0.99%, styrene 40 copies,
and 200 parts of toluene were introduced into a flask equipped with a reflux condenser and a stirrer, and reacted at 80° C. for 20 hours in a nitrogen atmosphere.

After the reaction was completed, the contents of the flask were poured into about 15 times the amount of n-hexane to precipitate styrene homopolymer, which was removed by filtration. Next, the filtrate was concentrated to about one third, poured into about 10 times the volume of methanol to precipitate a polymer, filtered, and dried under reduced pressure to obtain 80 parts of a pale yellow polymer.

The average molecular weight of the light yellow polymer thus obtained was determined by high performance liquid chromatography (PUM) manufactured by Toyo Soda Kogyo Co., Ltd.
P: HLC-802A, DETECTOR: RI-8
000)] and a nuclear magnetic resonance absorption spectrum (measured with a JEOL Ltd. FX-90Q FT-NMR apparatus), it showed the following characteristic values and was confirmed to be a styrene-dimethylsiloxane block copolymer.

Number average molecular weight (hereinafter referred to as ■7) 6.01X10' weight average molecule! (hereinafter referred to as M) 1.33X10' dispersion ratio (hereinafter referred to as M, /M)> 2.22 Nuclear magnetic resonance absorption spectrum: 0.08 ppn+ (methyl group of dimethylsiloxane (hereinafter referred to as 5i-C10)] 6.56 ppm and 7.03 ppm (benzene ring of styrene (hereinafter referred to as -C4H6)) Weight proportion of dimethylsiloxane segment in the polymer (hereinafter referred to as Si-weight ratio): 61% Example 2 Used in Example 1 60 parts of the same polydimethylsiloxane compound, 40 parts of methyl methacrylate, and 200 parts of toluene were introduced into a flask equipped with a reflux condenser and a stirrer, and reacted in a nitrogen atmosphere at 80° C. for 20 hours.

After the reaction was completed, the contents of the flask were poured into about 15 times the amount of n-hexane to precipitate methyl methacrylate homopolymer, which was removed by filtration. Next, the filtrate was concentrated to about one third, and then poured into about 10 times the amount of methanol.
The polymer was precipitated, filtered, and dried under reduced pressure to obtain 70 parts of a pale yellow polymer.

When the physical properties of the pale yellow polymer thus obtained were measured in the same manner as in Example 1, it showed the following characteristic values,
It was confirmed to be a methyl methacrylate-dimethylsiloxane block copolymer.

πm 9.23 x 10z πM2.24X10' M, /M, 2.43 Nuclear magnetic resonance spectrum: 0, O8ppm (St-CL) 3.67ppn+ (Methyl ester group of methyl methacrylate (hereinafter referred to as -COOCHs group))] ]Si-
Weight ratio: 64% Example 3 Polydimethylsiloxane compound having a diacyl type peroxy group in the molecule represented by the following structural formula (2): % formula (2) with an average molecular weight of 12,000 and an active oxygen content of 0.61% 50 parts, 50 parts of styrene,
and 200 parts of toluene were introduced into a flask equipped with a reflux condenser and a stirrer.

Thereafter, 84 parts of a pale yellow polymer was obtained using the same manufacturing method as described in Example 1.

When the physical properties of the pale yellow polymer thus obtained were measured in the same manner as in Example 1, it showed the following characteristic values,
It was confirmed to be a styrene-dimethylsiloxane block copolymer.

M, 1.12X10' Ml,, 2.61 X 10' ■w/π, 12.33 Nuclear magnetic resonance spectrum: 0, O8ppm (Si-CHi) 6.56ppm and 7. O3ppm (-CJs)S
i-weight ratio: 52% Example 4 50 parts of the same polydimethylsiloxane compound used in Example 3, 50 parts of methyl methacrylate and 200 parts of toluene were introduced into a flask equipped with a reflux condenser and a stirrer.

Thereafter, 73 parts of a pale yellow polymer was obtained using the same method as described in Example 2.

When the physical properties of the pale yellow polymer thus obtained were measured in the same manner as in Example 1, it showed the following characteristic values,
It was confirmed to be a methyl methacrylate-dimethylsiloxane block copolymer.

■fi2.58X10' M, 6.58X10' ■, /M, 2.55 Nuclear magnetic resonance spectrum: 0, O8ppm (Si-CHz) 3.67ppm (-COOCHs) Si-weight ratio: 54% Example 5 Average Molecule II 15100 and active oxygen 10.37%
30 parts of a polydimethylsiloxane compound having a diacyl peroxy group in the molecule represented by the following structural formula (3), 70 parts of styrene, and 200 parts of toluene were introduced into a flask equipped with a reflux condenser and a stirrer, and the mixture was placed in a nitrogen atmosphere. The mixture was reacted at 90° C. for 20 hours.

-.-.-.-(3) The following procedure was carried out in the same manner as in Example 1 to obtain 87 parts of a white polymer.

When the physical properties of the thus obtained white polymer were measured in the same manner as in Example 1, it exhibited the characteristic values shown below, and was confirmed to be a styrene-dimethylsiloxane block copolymer.

πm2.88X10' πM? , 43
) Si-weight ratio: 32% Example 6 Average molecular weight 16500 and active oxygen ff 10.36%
30 parts of a polydimethylsiloxane compound having a diacyl peroxy group in the molecule represented by the following structural formula (4), 70 parts of methyl methacrylate, and 200 parts of toluene.
A portion was introduced into a flask equipped with a reflux condenser and a stirrer, and reacted at 90° C. for 20 hours in a nitrogen atmosphere. The following procedure was carried out in the same manner as described in Example 2 to obtain 75 parts of a white polymer.

... (4) When the physical properties of the thus obtained white polymer were measured in the same manner as in Example 1, it exhibited the characteristic values shown below, and was confirmed to be a methyl methacrylate-dimethylsiloxane block copolymer.

■, 5.81 7 30 parts of the same polydimethylsiloxane compound used in Example 5, 70 parts of vinyl acetate, and 20 parts of toluene
0 part was introduced into a flask equipped with a reflux condenser and a stirrer, and reacted at 90° C. for 20 hours in a nitrogen atmosphere. After the reaction was completed, the contents of the flask were poured into about 15 times the amount of methanol to precipitate the polymer, and the polymer was obtained by filtration. After drying under reduced pressure, 72 parts of a white polymer was obtained.

When the physical properties of the pale yellow polymer thus obtained were measured in the same manner as in Example 1, it showed the following characteristic values,
It was confirmed to be a vinyl acetate-dimethylsiloxane block copolymer.

M,, 7.11X10' M, 2.25X10' M, /π, 3.16 Nuclear magnetic resonance spectrum: 0, O8ppm (Si-Cfl:+)2, llppm
(Methyl group of vinyl acetate) Si-weight ratio: 34% Comparative Example 1 Instead of the polydimethylsiloxane compound with an average molecular weight of 10,000 used in Example 1, only the average molecular weight was 150.
40 parts of a white polymer was obtained in the same manner as in Example 1, except that 46 parts of polydimethylsiloxane different from 0 and 14 parts of lauroyl peroxide (purity 99%) were used.

When the nuclear magnetic resonance absorption spectrum of the thus obtained white polymer was measured, absorption of the methyl group of dimethylsiloxane (0.08 ppm) was confirmed, but absorption of the benzene ring of styrene (6.56 ppm and 7.0 ppm) was confirmed.
03 ppm) was not confirmed, and no styrene-dimethylsiloxane block copolymer was obtained.

Comparative Example 2 The same procedure was carried out except that 46 parts of polydimethylsiloxane having an average molecular weight different from 1500 and 14 parts of lauroyl peroxide (purity 99%) were used in place of the polydimethylsiloxane compound with an average molecular ffi of 10000 used in Example 2. Working in a manner similar to that described in Example 2, 40 parts of a white polymer were obtained.

When the nuclear magnetic resonance absorption spectrum of the thus obtained white polymer was measured, absorption of the methyl group of dimethylsiloxane (0.08 ppm) was observed.
Absorption of methyl ester group of methyl methacrylate (3,
67 ppm) was not confirmed, and no methyl methacrylate-dimethylsiloxane block copolymer was obtained.

Comparative Example 3 Instead of the polydimethylsiloxane compound with an average molecular fi of 15100 used in Example 7, a polydimethylsiloxane compound with an average molecular weight of only 4
22 parts of a white polymer was obtained by operating in the same manner as described in Example 7, except that 27 parts of a polydimethylsiloxane different from 800 and 2 parts of benzoyl peroxide (99% purity) were used.

When the nuclear magnetic resonance absorption spectrum of the thus obtained white polymer was measured, absorption of the methyl group of dimethylsiloxane (0.08 ppm) was confirmed, but absorption of the methyl group of vinyl acetate (2.11 ppm) was not confirmed. However, no vinyl acetate-dimethylsiloxane block copolymer was obtained.

Claims (1)

[Claims] (1) When polymerizing a vinyl monomer, the following structural formula (A): ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
(A) (In the formula, R_1 represents an alkyl group or an aryl group having 1 to 15 carbon atoms. In addition, R represents an alkylene group having 3 to 10 carbon atoms or a ▲ mathematical formula, chemical formula, table, etc. ▼ group,
R_2 represents an alkylene group having 1 to 15 carbon atoms or a phenylene group, and R_3 represents an alkylene group having 3 to 10 carbon atoms or a -(CH_2)_2O(CH_2)_3- group. Further, a dimethylsiloxane block characterized in that a polydimethylsiloxane compound having a diacyl peroxy group in the molecule represented by m is 10 to 200 and x is 2 to 10 is used as a radical polymerization initiator. Method for producing copolymer.