KR0142141B1 - Sylane coupling agent containing sulfur and process for preparing the same - Google Patents

Abstract

The present invention relates to an organosilane binder containing sulfur represented by the following general formula (I) and a method for producing the same.

Wherein R ¹ is (RO) ₃ Si, R ² is H, (RO) ₃ Si or (RO) ₂ MeSi, R is an alkyl group having 1 to 4 carbon atoms, n is 2 or 4;

Description

[Name of invention]

Sulfur-containing silane binders and methods for their preparation.

Brief description of the invention

The present invention relates to an organosilane binder containing sulfur represented by the following general formula (I) and a method for producing the same.

Wherein R ¹ is (RO) ₃ Si, R ² is H, (RO) ₃ Si or (RO) ₂ MeSi, R is an alkyl group having 1 to 4 carbon atoms, n is 2 or 4;

The organosilane binder according to the present invention is useful for chemically bonding two materials in order to enhance affinity and reinforcement of plastic or rubber and fillers in the production of plastic composites or rubber. In particular, the binder of the present invention can further increase the bonding strength because two or three silane groups in the molecule that can be hydrolyzed to bind with the filler.

Silicone binder is an important material widely used in the manufacture of composites and rubbers of plastics, and it promotes bonding strength by blending plastics with inorganic fillers having different physical properties. Therefore, the desired physical properties can be given to the plastic or rubber, so that the economic efficiency of the plastic can be maximized.

The general molecular structure of the silicone binder is represented by Y (R) Si (OR ') ₃ , where the Si (OR') ₃ moiety becomes silanol represented by Si (OR ') ₃ when hydrolyzed. In the above formula, Y represents an organic functional group capable of reacting with a plastic or a resin, and R is an organic gig linking the organic functional group and silicon, and most of them are methylene, ethylene, or propylene groups. The silanol is unstable and condenses with each other or chemically bonds with the metal hydroxyl group of the metal oxide on the surface of the inorganic filler to enhance the reinforcement of the filler. Currently, silane binders containing sulfur are widely used in the preparation of rubber polymers.

G. M. Omitanski and H.E. Petty reported that gammachloropropylmethoxysilane can be synthesized in US Pat. No. 3,849,471. R. P. Louthan reported in US Pat. No. 3,890,213 that the synthesis of gammalmacttoethyl trimethoxysilane can be achieved by adding hydrogen emulsification to the vinyltrimethoxysilane.

JY Mui et al., In US Pat. Nos. 4,044,037 and 4,099,981, reported that silicone binders substituted with phenyl groups having an aromatic group in the aromatic group are better for rubber reinforcement than silicone binders in which the silicon and multo earth groups are aliphatic groups. . In this patent, a process for preparing a silicone binder having such a multotophenyl group has been reported. The process first synthesizes tolylethyltrichlorosilane by adding trichlorosilane to a hydrogensilification reaction to vinyltoluene under a platinum catalyst, This tolylethyl trichlorosilane was reacted with sulfur monochloride to synthesize polysulfide, and then polysulfide was reacted with methanol to change the tricoltosilyl group of polysulfide to trimethoxysilyl group, and the polysulfide was reacted under a cobalt sulfide catalyst. The process is quite complicated and difficult because it consists of reducing to hydrogen at high pressure to obtain mercetotophenylethyltrimethoxysilane. In addition, since the binder prepared by this method contains mullite earthenware, there is a severe odor in the product, which is difficult to handle and use.

MS Eugen et al. In Germany Patent No. 2,141, 159 of rubber and fillers in which bis [ω-trialkoxysilyl) alkylpolysulfides synthesized by refluxing a colloalkyltrialkoxysilane and sodium polysulfide in an alcohol solvent can be bonded with sulfur. It has been reported to exhibit good properties as a binder.

However, as known from Eugen et al., A compound having a trialkoxysilane end is bound to a filler by one silane group per molecule when combined with the filler, and thus, when used with a filler having poor bonding strength with a silane group, the compound has a low binding force. The performance of the binder will be degraded.

In order to make up for the shortcomings in the prior art, the present invention provides a polysulfidesilane-based binder.

Since the polysulfide silane binder of the present invention is thermally unstable, when the plastic or rubber is cured, the bond between sulfur and sulfur in the binder is broken to form a chemical bond with the plastic or rubber.

Polysulfide-based binder according to the present invention has a relatively simple synthesis method compared to the conventional binder production method, there is no odor as in the multo earth compound is easy to handle and use, and less waste during synthesis. In addition, by providing two or three silane groups that can be combined with the filler per molecule of the binder, the crosslinking between the plastic or the rubber and the filler can be more powerful, which not only reduces the wear of the product, but also affects other physical properties. .

The function of the binder is to create a strong chemical bond between the filler and the rubber polymer, so the choice of a suitable binder for each polymer-filler is important. It is recommended to select a binder through experimentation. The binder may be used by reacting with a filler before adding it to the rubber polymer, or may be used by reacting with rubber before adding the filler.

As prepared by the present invention, the silane binder containing sulfur as a functional group has very good stress-strain properties and tear-strengths without seriously affecting the stability of the processiong scorch when used in the manufacture of cured rubbers using inorganic fillers. It is known to reduce heat formed when it is bent. It also shows very high modulus values, indicating that the dynamic physical properties such as wear resistance are improved. The rubber to which the sulfur-containing silane binder can be applied is a non-pourable curable unsaturated rubber polymer, and non-pourabl refers to a curable rubber polymer that does not flow at about 25 ° C. The elastomer Nanuak (1972 edition, Interational Institute of Synthetic) Rubber Producers published) include natural and synthetic rubber polymers such as styrenebutadiene, butadiene, ethylene-propylene, chloroprene, nitrile, bromo or chlorobutyl, polyisoprene.

Inorganic fillers that can be used with the binder of the present invention include hydrated precipitated silica, fumed silica, silica erotic gel, silica zero gel and aluminum silicate, calcium silicate, calcium metasilicate or magnesium silicate such as magnesium silicate, aluminum oxide (including hydrates). ), Metal oxides such as titanium dioxide, zinc oxide, zirconium oxide, inorganic fibers such as glass fibers or metal fibers may be used, and silica based fillers are particularly preferred.

The binder of the present invention is mixed with the filler stock and added to the rubber polymer batch before adding other additives. In some cases, the hydrolyzate and condensate of the binder may be reacted with the filler to be used. The binder of the present invention uses 0.1 to 20% of the weight of the inorganic filler, but preferably 1 to 10%. The polysulfide silane and its hydrolyzate and condensate of the present invention can be applied to adhesives, protective coatings, metal softening agents, antioxidants, surface treatment agents of fillers and the like.

The present invention also provides a method for preparing a compound of formula (I).

The preparation method of the present invention consists of heating and stirring the general formula (II) compound and the general formula (III) compound in an alcohol solvent.

Wherein R ¹ is (RO) ₃ Si, R ² is H, (RO) ₃ Si or (RO) ₂ MeSi, R is an alkyl group having 1 to 4 carbon atoms, Y is an alkali element, preferably Na n is 2 or 4.

A method for preparing sodium sulfide, which is preferable as the compound of general formula (III), is a method of reacting sodium sulfide with sulfur in an aqueous solution state (SR Sandler, W. Karo, Ploymer Syntheses, Vol. III, Organic Chemistry a Series of Monographs, Vol. 29 , Wasserman Ed, Academic Press, 1980, p 71), and a method of melting sodium sulfide and sulfur at 500 ° C. (G. Brauer Ed. Handbook of Preparative Inorganic Chemistry Vol. 1 2nd Ed.), Academic Press, New York, 1963, pp. 357-369) are common, but the method of melt | melting and synthesizing is preferable in order to synthesize | combine in large quantities.

The general formula (II) compounds used as starting materials in the preparation method of the present invention can be prepared by the inventors' patented and patented methods. In other words, the present inventors have reported that a mixture of methylene chloride and hydrogen chloride can be reacted with silicon to synthesize bissilylmethane having Si—H bonds (Jung Il Nam et al., US Pat. No. 5,233,069) and unsaturated bonds to the compounds according to this patent. It has been reported that the addition of an organic substance having a compound of formula (II) wherein R ¹ is (RO) ₃ Si and R ² is H by addition and hydrogenation of the silicon-sintering reaction (Il Nam et al., Korea) Patent application 92-12998, July 21, 1992). In addition, the present inventors have reported that trissilylmethane having Si—H bonds can be synthesized by reacting a mixture of chloroform and hydrogen chloride with silicon in the same manner (Jung Il Nam et al., Korean Patent Application 92-10293). It is reported that the organic compound having an unsaturated bond can be synthesized by adding a hydrogen siliconation reaction and subjecting alcohol to a reaction of alcohol, where R ¹ is (RO) ₃ Si and R ² is (RO) ₃ Si. (Jung Il Nam et al., Korea Patent Application 92-16148). When (trichlorosilyl) methyldichlorosilane is used instead of chloroform in synthesizing trissilylmethane according to the above method, trissilylmethane having a methyldichlorosilyl group and a Si-H bond can be synthesized. When the reaction mixture is added with a hydrogen siliconization reaction and alcoholated, R ¹ is (RO) ₃ Si and R ² is (RO) ₂ MeSi.

The alcohol used in the production method of the present invention preferably uses an alcohol having the same carbon as R in general formula so as not to cause an exchange reaction with the alkoxy group of the silane. The reaction temperature is in the range of 20 ℃ to 150 ℃ but when using a lower alcohol such as methanol or ethanol it is preferable to react while refluxing at the boiling point of the alcohol used.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1

Preparation of Sodium Tetrasulfide

A 1 L three-necked flask was equipped with a mechanical stirrer and a reflux condenser, and 106 g (3.31 mol) of sulfur was added thereto. 263 g (1.10 mol) of sodium sulfide dihydrate were dissolved in 350 ml of distilled water and placed in a flask. At reflux with vigorous stirring, the color of the solution turned dark red. After refluxing for 1 hour, about 400 ml of water was removed by simple distillation. 150 ml of benzene was added and the water was removed while refluxing for 10 hours using a Dean-Stark apparatus. The solid solidified on the flask wall was scraped off and dried in a vacuum oven at 180 ° C. for 8 hours to obtain 169.9 g of sodium tetrasulfide (yellow solid, yield 88%).

Example 2

4.18 g (0.024 mol) of sodium tetrasulfide prepared in Example 1 was added to a 100 mL flask, and 315.15 g of 6-chloro-1,1,1,3,3-pentamethoxy-1,3-disilahexane ( 0.05 mol) and 40 ml of anhydrous methyl alcohol were added thereto. The methanol was stirred at reflux for 18 hours. The resulting sodium chloride was isolated by filtration with filter needles wrapped around the filter paper, and the remaining salts were extracted twice with 10 ml of methanol each, filtered and combined with the first filtrate. Simple distillation removed the methanol. 30 ml of hexane was added to the residue, followed by stirring. The filter paper was again filtered through a needle wrapped around the filter paper to obtain a filtrate, and simple distillation removed hexane from the filtrate. The solvent was removed under reduced pressure in vacuo to give 14.75 g of a yellow solution.

¹ H-NMR (300 MHz, CDCl ₃ ): δ 0.03 (S, 4H, SiCH ₂ Si), 0.75-0.85 (m, 4H, CH ₂ ),

1.80 to 1.90 (m, 4H, CH ₂ ), 2.63 to 3.03 (m, 4H, CH ₂ S), 3.53 (s, 12H, OCH ₃ ),

3.57 (s, 18H, OCH ₂ )

Example 3

4.18 g (0.024 mol) of sodium tetrasulfide prepared in Example 1 was added to a 100 ml flask, and 6-chloro-1,1,1,3,3-pentamethoxy-2-trimethoxysilyl-1,3 21.15 g (0.05 mol) of disilahexane and 40 ml of anhydrous methanol were added thereto. The methanol was stirred at reflux for 18 hours. The resulting sodium chloride was isolated by filtration with filter needles wrapped around the filter paper, and the remaining salts were extracted twice with 10 ml of methanol each, filtered and combined with the first filtrate. Simple distillation removed the methanol. 30 ml of hexane was added to the residue, followed by stirring. The filter paper was again filtered through a needle wrapped around the filter paper to obtain a filtrate, and simple distillation removed hexane from the filtrate. The residue was removed under reduced pressure in vacuo to give 20.78 g of a yellow solution.

¹ H-NMR (300 MHz, CDCl ₃ ): δ 0.07 (S, 2H, SiCH), 0.82-0.91 (m, 4H, CH ₂ ),

1.80 to 1.90 (m, 4H, CH ₂ ), 2.63 to 3.03 (m, 4H, CH ₂ S), 3.53 (s, 12H, OCH ₃ ),

3.58 (s, 36H, OCH ₃ )

Example 4

4.18 g (0.024 mol) of sodium tetrasulfide prepared in Example 1 was placed in a 100 ml flask, and 7-chloro-2,2,4,4-tetramethoxy-3-trimethoxysilyl-2,4-di 20.35 g (0.05 mol) of silahexane and 40 ml of anhydrous methyl alcohol were added thereto. The methanol was stirred at reflux for 18 hours. The resulting sodium chloride was isolated by filtration with filter needles wrapped around the filter paper, and the remaining salts were extracted twice with 10 ml of methanol each, filtered and combined with the first filtrate. Simple distillation removed the methanol. 30 ml of hexane was added to the residue, followed by stirring. The filter paper was again filtered through a needle wrapped around the filter paper to obtain a filtrate, and simple distillation was performed to remove hexane. Removal of the residual solvent under reduced pressure in vacuo afforded 19.05 g of a yellow solution.

¹ H-NMR (300MHz, CDCl ₃ ): δ 0.06 (S, 2H, SiCH), 0.04 (S, 6H, SiCH ₃ ),

0.82 to 0.91 (m, 4H, CH ₂ ), 1.80 to 1.90 (m, 4H, CH ₂ ), 2.63 to 3.03 (m, 4H, CH ₂ S),

3.53 (s, 12H, OCH ₃ ), 3.55 (s, 12H, OCH ₃ ), 3.58 (s, 18H, OCH ₃ )

Claims (4)

Organosilane represented by general formula (I); Wherein R ¹ is (RO) ₃ Si, R ² is H, (RO) ₃ Si or (RO) ₂ MeSi, R is an alkyl group having 1 to 4 carbon atoms, n is 2 or 4; A process for preparing a compound of formula (I) comprising reacting a compound of formula (II) with a compound of formula (III) in an alcohol solution at 20 ° C. to 150 ° C .; Wherein R ¹ is (RO) ₃ Si, R ² is H, (RO) ₃ Si or (RO) ₂ MeSi, R is an alkyl group having 1 to 4 carbon atoms, Y is an alkali element, n is 2 or 4 to be. The process according to claim 2, wherein the alcohol is an alcohol having the same number of carbons as R of the general formula (II) compound. The process according to claim 2, wherein the reaction is carried out at the boiling temperature of the solvent.