JPS59213764A - Instant production of single liquid type rtv composition curable promotor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION The present invention relates to alkoxy-functional-corrugated RTV silicone rubber compositions, and more particularly to alkoxy-functional-corrugated RTV silicone rubber compositions in which cure accelerators are formed in situ in the composition. It relates to RTV silicone rubber compositions.

Single wave RTV silicone rubber compositions have been known for some time. The initial composition is acyloxy functional, ie the crosslinking agent is acyloxy functional. Compositions of this type are packaged in a one-component container in a substantially anhydrous state. When it is desired to harden the composition, the seal of the cyst is broken. The composition cures into a silicone elastomer when exposed to moisture in the air. Recently, alkoxy-functionalized-corrugated RTV silicone rubber compositions have been developed. That is, the crosslinking agent is an alkoxy-functional silane such as methyltrimethoxysilane. Examples of such compositions that are commercially available are B
EER3 is described in US Pat. No. 10-19. Compositions of this type include a silanol-terminated diorganopolysiloxane polymer, a monoalkoxysilane crosslinker,
It consists of a titanium chelate catalyst as a condensation catalyst, a filler and various other additives.

Although the compositions of the above patents are commercially available and have a shelf life of 7 years or more and a practical cure rate, there are still problems with these compositions.

It has been found that these compositions in some batches are so affected that the storage stability/or decreases rapidly after two months of storage. The fact is that in most cases the shelf life of compositions of this type is affected even after Ω weeks of storage. Additionally, some batches of the above compositions have a curing rate that is practically unacceptable. Various improvements have been made to the above compositions which have reduced these obstacles to some extent, but have not completely eliminated them.

Improved commercially available alkoxy-functional-deep RTV silicone rubber compositions are disclosed in U.S. Patent Application No. 27 to WHITE et al.
7J, 2 yen issue. As postulated therein, it is believed that unbound hydroxyl groups in the RTV composition may cause decomposition of the alkoxy groups on the terminal silicon atoms of the diorganopolysiloxane-based polymer. Furthermore, it is speculated that such decomposition of the alkoxy groups results in a gradual decrease in the curing rate and storage stability of the RTV composition during storage.

As mentioned above, improved RTV alkoxy functional-deep RTV silicone rubber compositions, i.e. improved storage stability and Compositions having a fast cure rate are disclosed in WRITE et al., US Patent Application No. 277.32, supra.

This silane scavenger acts to react with unbound hydroxyl groups in the RTV mixture, binding them and preventing them from decomposing the terminal alkoxy groups on the base diorganopolysiloxane polymer. . Therefore, the shelf life and cure rate of the composition are maintained even after long-term storage.

A satisfactory shelf life of a commercially available RTV silicone rubber composition should be such that it has a tack-free time of 20 minutes or more after storage for 7.2 months after manufacture. A more preferred composition is an alkoxy-functional deep RTV silicone rubber composition that has a tack-free time of 40 minutes or less after being stored in an anhydrous state in a container for a period of 7 years or more. . Such a composition is W
It has been developed as shown in U.S. Patent Application No. 277J2'1 to HITE et al. US Patent Application No. 277J2 to WHITE et al. indicates that the functional group of the silane scavenger can be an amino group.
This patent application also indicates that curing accelerators selected from amines and guanidines may optionally be present.

MITCHELL's U.S. Patent Application No. 1. It is also important to look at No. 9, which describes the use of alkoxy-functional deep RTV silicone rubber compositions similar to those described in U.S. Patent Application No. 221, issued by ITE et al. The use of certain alkoxy-functional amine-functional siloxane scavengers or crosslinker-scavengers is disclosed.

US Pat. No. 277J2'1 to WHITE et al. discloses that, per 100 parts of a silanol-terminated diorganopolysiloxane polymer, a curing accelerator is added at θ/~1, preferably 07-7.
It is indicated that it may be included in a concentration of 0.3 to 7 parts, preferably 0.3 to 7 parts. Furthermore, at this concentration of accelerator, after accelerated aging of the uncured composition, the composition
It has also been shown to have a tack free time of less than 0 minutes. This patent application discloses that the crosslinking agent and scavenger or scavenger is used in excess of up to three parts, based on the base polymer, over the amount necessary to end-capped the base silanol-terminated diorganopolysiloxane polymer. It is also stated that it is preferable that the According to the case of WHITE et al., U.S. Patent Application No. 277.3.2, silanol-terminated diorganopolysiloxane polymer base 70
0 parts by weight, for the purpose of end-capping the base polymer.
It is desirable to add up to 1 part of crosslinker and scavenger, and up to an additional 3 parts by weight of crosslinker and scavenger for scavenging purposes, and more generally from 67 to 5 parts, more preferably from 0.3 to 7. It is desirable to add one type of amine curing accelerator.

Surprisingly, instead of adding the crosslinker/scavenger and accelerator separately, if the crosslinker/scavenger is amine-functional, that is all that is needed;
Alternatively, it has been found that sufficient secondary amines are liberated to act as curing accelerators.

One of the objects of the present invention is the alkoxy functional i-wave type R'T
To demonstrate a method for forming an amine cure accelerator in situ in V silicone rubber compositions.

Another object of the present invention is to demonstrate a method for producing an amine-functional accelerator in situ by reacting an amine-functional crosslinker and scavenger with a silanol-terminated diorganopolysiloxane polymer.

Additionally, it is another object of the present invention to utilize primary and secondary amine-functional crosslinkers and scavengers in alkoxy-functional molded RTV silicone rubber compositions by reacting them with silanol-terminated diorganopolysiloxane polymers. The purpose of this invention is to demonstrate a method for producing amine-functional cure accelerators in situ.

By forming in situ an amine-functional cure accelerator that results in a final uncured composition having a tack-free time of 2 minutes or less after a storage period of 7 years or more.
It is another object of the present invention to provide a method for making alkoxy-functional-liquid RTV silicone rubber compositions.

These and other objects of the present invention are achieved by the invention set forth below.

SUMMARY OF THE INVENTION In accordance with the above objects, (A) 700 parts by weight of a silanol-terminated polydicasiloxane consisting essentially of chemically bonded units of formula (B) % of formula (2) for hydroxy functional groups; at least one part of a silane scavenger having the formula % (1), 0 to 10 parts of a crosslinking silane having the formula % (2), (D) an effective amount of a condensation catalyst (wherein R is Cj-13 selected from monovalent substituted or unsubstituted hydrocarbon groups, R1 is a C4-8 aliphatic organic group selected from the group consisting of alkyl, alkyl ether, alkyl ester, alkyl ketone and alkyl cyano group;
7-13 furalkyl group, R2 is a monovalent substituted or unsubstituted hydrocarbon group of Cl-13, X is an amino hydrolyzable leaving group, a is an integer of / to 3, b is an integer of 0 or /, a + b A method for producing a substantially acid-free one-component silicone rubber composition in which a curing accelerator is formed immediately upon mixing the components, the sum of the components is /~3). Empowered by the present invention.

The compounds of formula (1) are crosslinkers and scavengers in which X is a primary or secondary amine, more preferably a secondary amine. When the cross-linking agent and scavenger of formula (1) reacts with the silanol-terminated diorganopolysiloxane polymer and is liberated to cap the ends, the secondary amine acts as an end-tapping catalyst and also acts as a curing accelerator. work. Free primary amines also act in a similar manner. Additionally, extra crosslinking agent of formula (2) may optionally be added to the composition in order to terminate the silanol-terminated diorganopolysiloxane polymer base as much as possible with terminal alkoxy groups.

The crosslinking agent and scavenger can be silane or siloxane.
When reacting with the silanol groups on the diorganopolysiloxane polymer, the primary or secondary amine is released, and the terminals of the silanol-terminated diorganopolysiloxane polymer base are bonded by a crosslinking agent and scavenger. It acts as a catalytic end-chipping catalyst and also acts as a cure accelerator to maintain the tack-free time of the composition preferably below 3-theta minutes after storage for a period of 7 years or more.

A preferred crosslinking agent is methyltrimethoxysilane and a preferred silane scavenger is methyldimethoxy (di-N
-hexylamino)silane.

Additionally, in order for the composition to cure to obtain the properties of RT'V silicone rubber compositions (RTV refers to room temperature vulcanizability in this application), the composition preferably contains a condensation catalyst.
For example, it is necessary to contain a tin condensation catalyst such as dibutyltin dilaurate or dibutyltin diacetate.

DESCRIPTION OF PREFERRED EMBODIMENTS As described above, for the production of commercially available products, i.e., those exhibiting storage stability of approximately 2 to 72 months and having a tack-free time after the storage period of 20 minutes or less. contains silanol-terminated geo/L-cappolysiloxane polymer 70
For every 0 parts, there must be at least about 3 parts of crosslinker and scavenger present. Preferred storage-stable alkoxy-functionalized RTV compositions include storage-stable compositions that can be stored for a period of 7 years or more and have a tack-free time of 0 minutes or less after storage for that period. It is a thing. To obtain such storage stability, it is necessary to have from about j to 7 parts of crosslinker and scavenger per 700 parts of silanol-terminated diorganopolysiloxane polymer. It is also possible to use more than 7 parts of crosslinker and scavenger, but no beneficial results are obtained. It must be noted that the minimum value of the crosslinking part is the lowest limit determined by experiments with the crosslinking agent of Example (2).

This minimum value varies to some extent depending on the type of amine-functional crosslinker and scavenger.

Therefore, in the specification and examples, it is referred to as a crosslinking agent and scavenger at least approximately in the composition. G-N-beefylamine is a secondary amine;
It is one of the more effective and preferred curing accelerators. Also,
It should be noted that in Example I, the di-N-hexylamine liberated as an in situ curing accelerator is a more effective curing accelerator compared to the primary amine. The results of Example 2 therefore indicate that the crosslinking agent forms an accelerator in situ for a composition with suitable storage stability and tack-free time. It reflects the lowest effective range for making alkoxy-functional silicone rubber compositions. Other amines liberated from the crosslinker/scavenger may be slightly more effective and therefore "at least about 100%" should be treated with an accelerator in situ to yield a composition that cures at a suitable rate. It is used as the minimum amount of crosslinking agent and scavenger required in the composition for manufacturing. The minimum amount of about 9 parts of crosslinker and scavenger cannot be predicted from the use of individual additives in the composition, as shown in U.S. Patent Application Ser. .

This effect is not cumulative. That application discloses that the curing accelerator is not formed in situ, but is a separate compound that is subsequently added to the composition during mixing or manufacturing of the composition. On page 70 of that application.

It has been shown that an excess of up to 3 weight q6 of scavenger may be used in the composition.

In the experiments reported in Example I of this application.

To obtain commercially viable compositions, at least 7 parts of crosslinker and scavenger are utilized for every 0 parts of silanol-terminated diorganopolysiloxane polymer/θ. Only 0.33 parts of crosslinker and scavenger are required to completely chain terminate the silanol-terminated diorganopolysiloxane polymer. This is a theoretical value. The above amount of crosslinker/scavenger is used as a curing accelerator and about 672 parts
N-hexylamine is liberated. Therefore, WHI T
According to the disclosure of U.S. Pat. Up to 3j parts of crosslinker and scavenger may be added to the composition. However, as the experimental results of Example I demonstrate, in order to produce a commercially practical R1゛v composition, that is, a composition with commercially practical storage stability and tack-free time, the composition It is necessary to contain a small amount (at least about 9 parts) of a crosslinking agent and scavenger.

Therefore, the above discussion points out that if the accelerator is formed in situ, the effect is cumulative as expected from the disclosure of WHITE et al., US Patent Application No. 277J-J. rather, it should be determined experimentally.

Nowhere in WRITE et al., US Patent Application No. 277.32, or other patents, is the in-situ formation of cure accelerators and the compositions of the present invention.

In this patent application as well as in other patent applications, the curing accelerator is a separate compound, a separate ingredient added to the composition during the mixing operation.

One of the advantages and fundamental advantages of the composition of the invention is:
The fact that the compositions are more easily formed in a continuous process, i.e., one component is added rather than two separate components, and thus the CI (UNG et al. U.S. Patent Application No. '137. The preparation of the composition is facilitated by continuously mixing the components in a devolatilizing extruder such as This is the case even though an agent-scavenger is used in the composition.Thus, the main advantage of the process of the present invention is that the alkoxy-functional a RT
V compositions, and more particularly, the continuous formation or manufacture of such compositions.

Referring to compounds of formula (1), such compounds are well known as shown in US Patent Application Ser. No. 27zz, 2g to WHITE et al. This compound is
Somewhat different from the compounds shown in U.S. Pat. be. Thus, from this crosslinking agent, it is possible to obtain compounds with only one alkoxy group on the terminal silicon atom and/or two alkoxy groups on the terminal silicon atom of the polymer chain.
It is possible to form a diorganopolysiloxane polymer base having 2 amino groups. Such compositions are included within the scope of the present invention and in accordance with the disclosure of the present invention.
harden. The formation of the polymeric base described above is also shown in LUCAS US Patent Application No. 9,10. formula(
The compound of 1) is disclosed in U.S. Patent Application No. 27 z32 of WHITE et al., which discloses that the crosslinker and scavenger must have at least two alkoxy groups.
LUCAS
U.S. Patent Application No. 19,103.
Therefore, WHI T E et al.'s U.S. Patent Application No. ! 77,
! Use a cross-linking agent and scavenger of 2 yen, or use LUCA
US Patent Application No. 'l￥9. Irrespective of whether a /θ type is used, in accordance with the present disclosure, a terminal silicon atom that forms a cure accelerator in situ and provides a composition with desirable storage stability and cure rate. 3
An end-stopped polymer having 5 alkoxy groups is formed.

When the crosslinker and scavenger of formula (1) chains terminates the silanol-terminated diorganopolysiloxane polymer, the amines (which may be primary or secondary) that are liberated are Application No. 277, j2'
It must be mentioned that it also acts as an end-binding catalyst according to the disclosure of No. 1. Other end-linked catalysts may be used as disclosed in US Patent Application No. 27,930 to CHUNG et al.

It is further noted above that the crosslinking silane of formula (2) ensures that maximum chain termination of the silanol-terminated diorganopolysiloxane polymer occurs and that the crosslinking density in the composition is high. It is disclosed that it may be used as an optional crosslinking agent in the composition.

In addition, together with or in place of silane, which is a crosslinking agent and scavenger of formula (1), the formula [wherein 1. R2 is as defined below and A is of formula B
ID -N-11 (wherein R10, R'' are independently selected from hydrogen and a C1-8 monovalent hydrocarbon group), and X is a group consisting of a simple amine of θθo to λJO. varies in range, y is 000
~． A cross-linking agent and scavenger may be used.

The compound of formula (3) differs from the compound of formula (1) in that it is a siloxane, but is also a crosslinking agent and scavenger.
This compound has at least 7 alkoxy groups, with 2 to
It has 20 silicon atoms. The amine functionality in the siloxane of formula (3) is either a simple primary or secondary amine.

A more preferred amine-functional siloxane crosslinker and scavenger compound is a compound of the formula:

[In the formula, R1 and R2 are as defined above, and A is the formula (in the formula, R
10, R'' are independently selected from hydrogen and C1-8-valent hydrocarbon groups), the simple amino group 5m varies in the range of 0/2 to 2JO, and n varies in the range of θ/ to Z9. , 0 is θ
The compound of formula (4) has at least three alkoxy groups in the polymer. Preferred crosslinker and scavenger siloxane compounds within the scope of compounds of formula (3). This compound also has 2 to 20 silicon atoms in the polymer chain. Regarding the amine functionality, the compound of formula (4) must have at least the same amount, i.e. 7 amino groups in the polymer, but the maximum amount is 1 possible with the compound of formula (3). There may be more amino groups in the polymer.
These compounds of formula (4) are therefore more preferred crosslinkers and scavengers. For further information regarding the preparation of compounds of formulas (3) and (4) and their use in preparing alkoxy-functional-corrugated RTV silicone rubber compositions, see MITCHELL U.S. Patent Application No. 93
The description in No. 2272 may be referred to. The same compound disclosed in that patent application is disclosed in the present application for the purpose of adding a cross-linker-cum-scavenger in the composition in order to generate a curing accelerator in situ in the composition. It is being done. For such compounds, especially those with high molecular weight and low amino groups, significantly higher amounts of such compounds may be incorporated into the composition than is the case for the simpler amines of formula (1), which is a minimum of about 9 parts, as discussed above. It is necessary to use it as a crosslinking agent and scavenger in the process.

Compounds of formulas (1), (3) and (4) are VVHIT
E et al. U.S. Patent Application No. 27Z Tag 2, LUCAS
U.S. Patent Application No. 270 and MITCHELL
U.S. Patent Application Ser. In order to generate in situ primary and secondary amine cure accelerators that improve the cure rate of the composition, the aforementioned amounts are added so that these components act not only as crosslinkers and scavengers but also as pure scavenger compounds. It can be mixed into the composition.

The silanol-terminated diorganopolysiloxane polymer preferably has the formula [wherein R is independently a monovalent substituted or unsubstituted hydrocarbon group of Cl-13 (preferably methyl or a large amount of methyl and a small amount of phenyl, cyanoethyl, trifluoropropyl, vinyl and mixtures thereof), where n is about lθ~
approximately 1 is an integer of θ]. Preferably the polymer has a molecular weight of 700 to about tioo,ooo as measured at about 2 J c.
It has a viscosity ranging from about <000 centipoise to about 2so, ooo centipoise.

n in formula (5) is j00~,2. A range of θ0θ is preferable.

Examples of groups included in H in formulas (1), (2), and (5) include aryl groups and halogenated aryl groups such as phenyl, tolyl, chlorophenyl, and naphthyl; aliphatic groups such as cyclohexyl and cyclobutyl; There are cycloaliphatic groups, alkyl and alkenyl groups such as methyl, ethyl, propyl, chloropropyl, vinyl, allyl, trifluoropropyl, and cyanoalkyl groups such as cyanoethyl, cyanopropyl, cyanobutyl. Examples of groups included in R1 preferably include C1-8 alkyl groups such as methyl, ethyl, propyl, butyl, and pentyl;
C7-+5 aralkyl groups such as benzyl and phenethyl, alkyl ether groups such as methoxyethyl,
an alkyl ester group such as 62-ace[·xyethyl, an alkyl ketone group such as /-butan-3-onyl,
There are alkylcyano groups such as cyanoethyl.
The group contained in R2 is the same as the group contained in R.

The groups R, 几1 and R2 are represented by the above-mentioned substitute formulas (1) and (2).
, (3), (4) and (5) and may be any of the groups identified above and may be the same or different in the compound or polymer.

The polyalkoxy-terminated polydiorganopolysiloxane produced by the reaction of the nosilanol-terminated diorganopolysiloxane polymer of formula (5) with the crosslinker/scavenger of formula (1) preferably has the following formula.

(In the formula, R, I(,' and R2 are as defined above, is an integer from about lo to approx.
One can be formed in a composition and mixed with other components of the composition in a variety of ways to form various types of mixtures.

One preferred example of such a mixture is (700 parts of a silanol-terminated polydicasiloxane consisting essentially of chemically bonded units of the formula (a), (b) one formula for the hydroxy functionality ( 2) a mixture consisting of at least two parts of a silane scavenger of formula (C), 0 to 10 parts of a crosslinking silane of formula (C), (d) an effective amount of a condensation catalyst; Polyalkoxy-terminated polydiorganosiloxane 7
00 parts, (b) 0 to 10 parts of a crosslinking silane of the formula (1%2)b ■ (R'0) (4-b) Sj, (C) an effective amount of a condensation catalyst.

A room temperature vulcanizable material selected from

(However, JRl, R2 and X are as defined in the standard definition, and a is /
An integer of ~3, b is an integer of 0 or /, a+b is /~3, e
is an integer of θ~2, b+e is θ~2, n is about 50~2j0
(integer up to 0) such compositions can also be prepared utilizing crosslinkers and scavengers of formula (3) and formula (4) in a mixture of the methods described above. In either case, a cure accelerator is formed which acts to provide the R,TV composition with suitable storage stability and cure rate. A preferred crosslinking agent for composition (2) in the present invention is methyltrimethoxysilane. Preferably R, R' and R2 are methyl.

Additionally, the composition needs to have a condensation catalyst if it is to be crosslinked to a certain density and cured to have the properties that silicone rubber compositions normally have. A preferred condensation catalyst is a tin condensation catalyst.

An effective amount of condensation catalyst that can be used to facilitate curing of RT V compositions in embodiments of the present invention is 1
For example, the amount is 9007 to 7 parts based on the weight of 700 parts of the silanol-terminated polydiorganosiloxane of formula (1). Tin compounds include 5 such as dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dimethoxide, carpomethoxyphenyltin trisuberate, tin octoate, isobutyltin triceroate, dimethyltin dibutyrate, dimethyltin dineodeconate, and triethyltin. These include tin tartrate, dibutyltin dibenzoate, tin oleate, tin naphthenate, butyltin tri-ethylhexoate, and tin butyrate.
Preferred condensation catalysts are tin compounds, with dibutyltin diacetate being particularly preferred.

Titanium compounds that can be used include, for example, /, 3-propanedioxytitanium bis(ethyl acetoacetate), /, 3
-Propanedioxytitanium bis(acetylacetonate)% diisopropoxytitanium bis(acetylacetonate), titanium naphthenate, tetrabutyl titanate, tetra-ditanate - ethylhexyl, tetraphenyl titanate, tetraoctadecyl titanate, ethyltriethanolamine It is titanate. More WEYENB
Beta-dicarbonyl titanium compounds, such as those shown in US Pat. No. 333-07 to ERG, can also be used as condensation catalysts in the present invention.

Zirconium compounds such as zirconium octoate can also be used.

Furthermore, examples of metal condensation catalysts include, for example, lead λ-ethyl octanoate, iron 2-ethylhexanoate, cobalt ethyl hexanoate, manganese 2-ethyl hexanoate, and monoethylhexane. These include zinc acid, antimony octoate, bismuth naphthenate, zinc naphthenate, and zinc stearate.

Examples of non-metallic condensation catalysts are hexylammonium acetate and benzyltrimethylammonium acetate.

Various fillers and pigments can be incorporated into the silanol- or alkoxy-terminated orcappolysiloxanes, such as titanium dioxide, zirconium silicate, silica aerogels, iron oxides, diatomaceous earth, famed silica, carbon black, precipitated silica. , glass fiber, polyvinyl chloride, quartz powder, calcium carbonate, etc. The amount of filler used can vary within a wide range, obviously depending on its intended use. For example, in certain sealant applications, the curable compositions of the present invention can be used without fillers. In other applications, such as those using curable compositions to make binders, 200 parts or more of filler can be used per 00 parts organpolysiloxaref on a weight basis. In such applications, the filler consists of a large amount of filler, such as quartz powder, polyvinyl chloride, or mixtures thereof, and preferably has an average particle size in the range of about 7 to 70 microns.

The compositions of the invention can also be used as architectural sealants and caulking compounds. Therefore,
The exact amount of filler will depend on factors such as the application of the organopolysiloxane composition, the type of filler used (ie, the density of the filler and its particle size). Preferably, 70 to 300 parts of filler, including up to about 35 parts of reinforcing optical filler, such as a reinforced filler, are used per 100 parts of silanol-terminated organopolysiloxane.

As used hereinafter, the word "stable" used for the one-wave type polyalkoxy-terminated organopolysiloxane RT■ of the present invention means that it hardly changes unless exposed to atmospheric moisture and remains stable even after a long storage period. means a moisture-curable mixture that cures to a tack-free elastomer. In addition, stable RTV
means that the tack-free time exhibited by freshly mixed RTV components under atmospheric pressure conditions is temperature resistant for extended storage periods at ambient conditions or equivalent periods based on accelerated aging at elevated temperatures. exposed to atmospheric moisture after being kept in a moisture-free container. As indicated by a mixture of the same components, means almost the same.

In the context of defining an elastomer formed by exposing an RTV composition of the invention to atmospheric moisture, the expression "substantially acid-free" refers to a pka of jJ or greater, preferably B or thicker, particularly preferably 1
Means producing zero or more by-products.

In addition to the above ingredients, the composition may contain other ingredients such as plasticizers, sag control agents, adhesion promoters to provide low modulus. Examples of such additives are shown in BEER8 US Patent Application No. 3G9,537 and LUCAS US Patent Application No. 39,33f. The compositions can be made in a number of ways, but are most preferably made by mixing the crosslinking agent and scavenger with the silanol-terminated diorganopolysiloxane polymer in a substantially anhydrous manner, and then preparing for any terminal attachment. Add more catalyst. However, the reaction mixture is autocatalytic as described above. CHUNG et al. U.S. Patent Application No. 3
Other ingredients, including plasticizers, adhesion promoters, fillers, etc., can be added in subsequent mixing steps or at the point of mixing, as indicated in item m. Also, as long as a minimum amount of crosslinker and scavenger is present in the overall mix, excess crosslinker and scavenger can be removed in additional mixing steps, as shown in CHUNG et al., U.S. Pat. May be added. The minimum amount of each crosslinker and scavenger should be determined by the experiments shown above.

Once formed, the composition is packaged in a moisture-proof package in a substantially water-free manner, stored, and marketed as is. If the composition is desired to be cured, the package seal is broken and the composition is exposed to atmospheric moisture, thereby curing into a silicone elastomer that is completely cured in 2Z to 22 hours. As previously described, the composition may be manufactured continuously or semi-continuously as shown in U.S. Patent Application No. 3, No. 3, to CHUNG et al., or optionally may be manufactured or mixed batchwise. It's okay.

The following examples are presented for the purpose of illustrating the invention.
They are not presented for the purpose of limiting or delimiting the invention. All parts in the examples are by weight.

Preferred crosslinking agents and scavengers within the scope of formula (1) are Methyldimethoxy(di-N-hexylamino)silane.

Methyldimethoxy(di-N-methylamino)silane, Methyldimethoxyisopropylaminosilane, Methyldimethoxy(di-N-butylamino)silane, Methyldimethoxy(di-N-isobutylamino)silane, Methyldimethoxy(di-N-propyl) amine) silane, and methyldimethoxy(di-N-vinylamino)silane.

Preferred tin condensation catalysts for use in the present invention are dibutyltin diacetate and dibutyltin dilaurate.

Example I A stirrer, a pot thermometer, a water reflux condenser with an inlet for N2, and two (0230 ml!) tubes equipped with isobaric addition funnels.
Purge a liter three-hole flask with dry N2 and charge with 2F hexane. After stirring and purging with N2, the addition funnel was charged with CH. , S + (O CH-, ) 2 Cz i
Add 0 mol (/g 0 parts). The second addition funnel contains di-N-hexylamine/. 2J mole (23Z♂
section).

CH5 while stirring under an atmosphere of N2 at room temperature.
Rapidly add 1 c of S 1 (OCHs) 2 C to the hot mixture. Di-N-hexylamine is added dropwise to the rapidly stirred pot mixture over a period of 2 hours. A slight fever was observed, and the temperature of the pot was set to 262C.
Increase to ~33-C. A large amount of solid white triethylamine hydrochloride is produced during the reaction process. After stirring at room temperature/in the evening, solids are removed by vacuum filtration and liquid volatiles are removed by rotary flash evaporation under reduced pressure. Desired product by vacuum filtration, b-p. //3 ~//3 C
/ j + mm H, 9, 9 by chromatographic analysis
Produces methyldimethoxy(di-N-hexylamino)silane with e2% purity.

CHs-8i (OCH5)2-N(hexyl)2 was then mixed with the polymer, filler and Sn using a Semkit (registered trademark) mixer under anhydrous conditions.
Mix with +4 catalyst. Two catalyst addition steps are performed as follows.

At room temperature/! The first step consists of a mixing time of 2 min.
Silanol-terminated dimethylpolysiloxane polymer with a viscosity of d000 centipoise at IC! Parts by weight, parts by weight of octamethylcyclotetrasiloxane-treated fumed silica filler/metal dimethoxysilane, and 2 to 2 parts by weight of methyldimethoxycyhexylaminosilane are mixed as shown in Table 1 below. This mixture was taken and mixed in a second catalyst addition step in a Semkit® mixer at room temperature for an hour/night of mixing to add 623 parts of dibutyltin diacetate and! 00~/j-00 ppm with silanol content in the range of 2jtl? 27 parts by weight of a trimethylsiloxy-terminated dimethylpolysiloxane polymer having a viscosity of 10 θ centipoise are mixed.

After mixing, the RTV composition was packed into aluminum sealed tubes and kept at room temperature at 1.3-0% &H. Store at room temperature for 2 hours, at 10°C for 2 hours, and at 100C for 2 hours before exposure to a curing environment. The rate of cure and degree of cure are determined by tack free time (T, F.T) and 2g time durometer measurements. Acceptable vine cure is defined by TPT = 30 minutes, 62 hours durometer = 2. The results are shown in Table I.

Table 1 CH5S1 (OCH5) 2-N (Hexy Nori 2 results)
(OCH5) 2-N (Hexy Nori 2 Minimum Amount Example ■ 0CH5 CI-(5-8i -N -(n-Butyl)2OCH5 This observation, pot thermometer, water reflux condenser with N2 population, and 2 pieces A 3-day flask equipped with a 230 ml isobaric addition funnel was purged with dry N2, 2 liters of hexane and 2 mol (,X0rd) of :fJt.
Insert sl'J. After stirring and purging with N2, add CH35r(OCH=,)2C1l 70 to the addition funnel.
Add 0 moles (/0 parts). Add di-N-butylamine/phtamol (/Otsu/Otsu part) to a second addition funnel. While stirring at room temperature under N2 atmosphere, CH3S
Rapidly add 1(OCH,)2C4 to the pot mixture.

di-N-butylamine over 2 hours.

Add dropwise to the rapidly stirring pot mixture. A slight fever was observed, and the pot temperature was changed to 22C to 3J.
Increase to C. A large amount of solid white triethylamine hydrochloride is formed during the course of the reaction.

After stirring at room temperature for 71 hours, solids are removed by vacuum filtration and liquid volatiles are removed by rotary flash evaporation under reduced pressure. By vacuum filtration, the desired product, 7 mm
Methyl dimethoxy (di-N-
butylamino)silane is formed.

The aminosilane is then mixed with the polymer, filler, and tin catalyst using a 5 Semkit mixer under anhydrous conditions. The melt layer addition process is as follows. 5 parts of the same silanol-terminated dimethylpolysiloxane polymer as in Example 2, 75 parts of treated fumed silica filler as in Example 2, and 2 to 5 parts of aminosilane to give a concentration of 2 to 1 parts in the mixture. Add. This mixture is mixed at room temperature/overnight in a first mixing step.

Dibutyltin diacetate θ is added to this initial mixture in the catalyst addition after the mixing step at room temperature/ohm in a Semkit® mixer. Part 8 and evening 00~/evening 0
Contains silanols in the range of 0 ppm and 10
A trimethylsiloxy-terminated dimethylpolysiloxane polymer having a viscosity of θ centipoise is added and mixed.

Curing data obtained from the above compositions, including accelerated aging and tack-free time where applicable, are shown in Table 1 below.

Table ■

Claims (1)

[Scope of Claims] / (a) 700 parts by weight of a silanol-terminated polydiorganosiloxane consisting essentially of chemically bonded units of formula (b) % of formula (2) for hydroxy functional groups; (C) 0 to /θ parts of a crosslinking silane having formula (2) (% formula %); (d) an effective amount of a condensation catalyst (wherein R is C4- 43 monovalent substituted or unsubstituted hydrocarbon groups and R+ is selected from the group consisting of alkyl, alkyl ether, alkyl ester, alkyl ketone and alkyl cyano group or C7
-45 alkyl group, R2 is monovalently substituted or unsubstituted C4-
+S hydrocarbon group, X is amino hydrolyzable leaving group, a is /
An integer of ~3, b is an integer of 0 or /, the sum of a+b is /~
3) to produce a substantially acid-free, one-component room temperature vulcanizable silicone rubber composition in which a curing accelerator is formed in situ as soon as the components are mixed. Method. 2. The method according to claim 1, wherein the crosslinking agent is methyltrimethoxysilane. 3. The method according to claim 2, wherein 3R,RmiR2 is methyl. The method according to claim 3, wherein the condensation catalyst is a tin compound. The method of claim 1, wherein the condensation catalyst is selected from the group consisting of dibutyltin dilaurate and dibutyltin diacetate. B Silan scavenger is methyl dimethoxy (G-N-
2. The method of claim 1, wherein the silane is hexylamino)silane. 2. The method of claim 1, wherein the silane scavenger is methylmethoxydi-N-methylaminosilane. and The method of claim 1, wherein the silane scavenger is methyldimethoxyisopropylaminosilane. ? A substantially acid-free, room temperature vulcanizable organopolysiloxane composition that uses an effective amount of condensation catalyst with a silanol-terminated orcappolysiloxane and a polyalkoxysilane crosslinker to generate cure accelerators in situ upon mixing of the ingredients. 700 parts by weight of a silanol-terminated organopolysiloxane are added to 700 parts by weight of a silanol-terminated organopolysiloxane under substantially anhydrous conditions. C1-8 aliphatic organic groups selected from the group consisting of ketones and alkylcyano groups or c, -13
aralkyl group, R2 is a monovalent substituted or unsubstituted hydrocarbon group of Cl-13, X is an amino hydrolyzable leaving group, a is /~
An integer of 3, b is an integer of 0 or /, the sum of a plus is /~3
at least about 9 parts by weight of a polyalkoxysilane which is a scavenger for hydroxy functional groups and a crosslinking agent of
An improved method comprising subsequently adding an effective amount of condensation catalyst. /θ The method according to claim 2, wherein the crosslinking agent is methyltrimethoxysilane. //: The method of claim 70, wherein R, R' and R2 are methyl. /2 Claim 1 in which the condensation catalyst is a tin compound
/The method described in section. /3 Claim 1, wherein the condensation catalyst is selected from the group consisting of dibutyltin dilaurate and dibutyltin diacetate. ．． The method described in Section 2. The silane scavenger is methyl dimethoxy (G-N).
-hexylamino)silane. 2. The method of claim 2, wherein the silane scavenger is methylmethoxydi-N-methylaminosilane. 71. The method of claim 70, wherein the silane scavenger is methyltrimethoxyisopropylaminosilane. /7 Under substantially anhydrous conditions, o0C~/(ll'θ
°C) temperature: (i) 700 parts of a silanol-terminated polydicasiloxane consisting essentially of chemically bonded units of formula (a); (b) % of formula (2) for the hydroxy functional group; A mixture comprising at least a portion of a silane scavenger having the formula %() (), (C) 0 to 10 parts of a crosslinking silane of the formula (2) %(), and (d) an effective amount of a condensation catalyst. and (i+) polyalkoxy-terminated polydiorganosiloxane 7 of formula (a)
00 parts, (゛)5 sob (R"0) -5i (4b) 0 to 10 parts of a crosslinking silane, (C) an effective amount of a condensation catalyst (wherein R is C
113 monovalent substituted or unsubstituted hydrocarbon group, R is C1- selected from the group consisting of alkyl, alkyl ether, alkyl ester, alkyl ketone and alkyl cyano group;
8 aliphatic organic group or C7-15 alkaryl group, R
2 is a C1-13 monovalent substituted or unsubstituted hydrocarbon group, X is a hydrolyzable amine leaving group, a is an integer of / to 3, b is an integer of θ or /, the sum of a + b is / to 3, e is an integer of θ~2, the sum of b10 is θ~, 2, n is about 50 to about, 21θ0
A method comprising stirring a room-temperature vulcanizable material selected from a mixture of vulcanizable materials (an integer having a value up to A method of producing a substantially acid-free single-wave room temperature vulcanizable composition that can be cured to an elastic state. 700 parts of a silanol-terminated polydiorganosiloxane consisting essentially of chemically bonded units of the formula: Generally, A is a group consisting of a simple amino group of the formula R+ O -R1i (wherein R+0 and B11 are each selected from hydrogen and a C1-8 monovalent hydrocarbon group), and x is 00 ~, 2JO range, y is θ00~
2 evening 0 range, W is θoj~/evening range, X+y +w
(c) at least about 7 parts of a siloxane scavenger having a total of 70 to 3θ0; (C) 0 to 10 parts of a crosslinking silane of formula %); Catalyst (wherein R is selected from monovalent substituted or unsubstituted hydrocarbon groups of CI-13, R1 is alkyl, alkyl ether,
cl-8 aliphatic group selected from the group consisting of alkyl esters, alkyl ketones and alkyl cyano groups, or C7-j! 1 aralkyl group, R2 is a C1-43-substituted or unsubstituted hydrocarbon group, b is θ or /), the curing accelerator is generated in situ immediately after mixing the components, substantially A method for producing a one-component room temperature vulcanizable silicone rubber composition that does not generate acid. /9 The method according to claim 1 (f''), in which the crosslinking agent is methyltrimethoxysilane. The method according to claim 72, in which R5R1 and R2 are methyl.2 /Claim 2 in which the condensation catalyst is a tin compound
The method described in section θ. , 22. 28. The method of claim 27, wherein the condensation catalyst is selected from the group consisting of dibutyltin dilaurate and dibutyltin diacetate. 23 The siloxane scavenger has the formula [wherein R1 and R2 are as defined above, A is the formula 10 1 N gi+ where R10 and R+1 are each selected from hydrogen and a C1-8-valent hydrocarbon group]. Simple amino group, m is 0/3-
The range of υ0, n is the range of θ/~/9, 0 is θθta~no,
The range of θ0, the sum of m ten n + o, is 70 to 30
0] The method according to claim 1 and claim 1. A substantially acid-free, room-temperature vulcanizable organosystem that uses an effective amount of a condensation catalyst with a silanol-terminated organopolysiloxane and a polyalkoxysilane crosslinker to form a cure accelerator in situ upon mixing the components. In a method of preparing a polysiloxane composition under substantially anhydrous conditions, 100 parts by weight of a silanol-terminated organopolysiloxane is combined with a hydroxy functional group scavenger and crosslinking agent of the formula: A group consisting of a simple amino group (wherein R10 and R1'l are selected from hydrogen and C1-8 monovalent hydrocarbon groups, respectively), X is in the range of θ0ta to 2ta0, and y is 000. The range of 0, W is the range of θ0j~/evening, the sum of x+y+w is ノ,
/θ ~ 300, R1 is a C1-8 aliphatic organic group selected from alkyl, alkyl ether, alkyl ester, alkyl ketone, and alkyl cyano group, or C7
-13 aralkyl group, R2 is a C4-13 monovalent substituted or unsubstituted hydrocarbon group] and then add an effective amount of a condensation catalyst. , a method for improving the stability of the resulting room temperature vulcanizable organopolysiloxane composition. 2. The method according to claim 2, wherein the crosslinking agent is methyltrimethoxysilane. 23 Claim 2 in which R, R' and R2 are methyl! The method described in section. 2Z Claim 2 in which the condensation catalyst is a tin compound
The method described in paragraph (B). 28. The method of claim 27, wherein the condensation catalyst is selected from the group consisting of dibutyltin diacetate and dibutyltin dilaurate. , 29 The siloxane scavenger is a simple amino group of the formula % (wherein R10 and Rli are each selected from hydrogen and a C1-8 -valent hydrocarbon group), m is θ/
The range of O~2O0, n is the range of θ/~Z9, O is θ0!
~ノ, the range of 0θ, the sum of m + n + o is ko, 10
-300]. 3θ(+) 700 parts of a silanol-terminated polydiorganosiloxane consisting essentially of chemically bonded units of formula (a), (b) [wherein R, R' and R2 are as described below] , A is Equation 1
O n11 (in the formula, R1 (1 and R11 are each selected from hydrogen and a C1-8 monovalent hydrocarbon group) is a group consisting of a simple amino group, x is θθ, , (--, 2JO) Range, y is the range of 00θ~2JO, W is the range of θ03~/evening, X+
The sum of y + w is 2. /θ to 300]; (C) 0 to 10 parts of a crosslinking silane of formula %); (d) an effective amount of a condensation catalyst. and (ii) a polyalkoxy-terminated polydiorganosiloxane of the formula (a) 1
0 θ parts, (b) 0 to θ parts of a crosslinking silane of formula () % formula %, (c) an effective amount of a condensation catalyst (wherein R is selected from -substituted or unsubstituted hydrocarbon groups of C4-15); and R1 is a C1-8 aliphatic organic group or C7 selected from the group consisting of alkyl, alkyl ether, alkyl ester, alkyl ketone, and alkyl cyano group.
-13 alkaryl group, R2 is a C1-15 monovalent substituted or unsubstituted hydrocarbon group, X is a hydrolyzable amino leaving group, b
is an integer of 0 or /, e is an integer of θ~2, the sum of b+e is θ~2, and n is about 30~. ．． 2. A mixture of well-selected room temperature vulcanizable materials under substantially anhydrous conditions with θ
A process consisting of stirring at temperatures between 0 and 0 degrees Celsius, which forms a curing accelerator in situ as soon as the ingredients are mixed, a material that is curable to a solid elastic state, and which produces virtually no acids. A method of producing a corrugated room temperature vulcanizable composition. 3/ The siloxane scavenger compound has the formula [wherein R1,
R2 is as defined above, A is a simple amino group of the formula 10-N-R" (wherein R10 and R11 are each selected from hydrogen and a C1-8 monovalent hydrocarbon group), m is the range of θ/!; -230, n is the range of θ/~/θ, 0 is the range of θ01-2.00, the sum of m + n 10 is 2/
The method according to claim 3, wherein the range is from θ to 300.