JPS5819357A - Molding method - Google Patents

Abstract

PURPOSE:To obtain a silicone rubber molding with good releasability from a die, by heating a compsn. consisting of a vinyl group-contg. polyorganosiloxane, a specified polyorganohydrogensiloxane and Pt in a molding die. CONSTITUTION:A vinyl group-contg. polyorganosiloxane (A) contg. an average of at least two vinyl groups attached to Si atoms per molecule and having an average polymn. degree of 200-3,000, a polyorgano-hydrogen siloxane (B) contg. an average of at least 3 hydrogen atoms attached to Si atoms per molecule and having a viscosity of 20-1,000cP at 25 deg.C under conditions such that vapor pressure at 150 deg.C is controlled to 30Torr or lower, and 0.2-300ppm (in terms of Pt based on the combined amount of components A and B) Pt or Pt compd., are blended together, said component B being used in such a proportion as to give 0.5-10 hydrogen atoms attached to Si atoms per one vinyl group attached to a Si atom in component A. The resulting curable compsn. is charged in a molding die, molded and cured by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION The invention relates to a molding method for obtaining silicone rubber crystals with good releasability from a molding die, and more particularly, the invention relates to a molding method for obtaining silicone rubber crystals with good releasability from a molding die.
I111 This invention relates to a molding method for obtaining molded products with good properties.

Base polyorganic seal kit! - Silicone rubber, a rubber-like elastic material used for heating, is widely used in various fields due to its excellent heat resistance, electrical properties, ring resistance, durability, etc. This silicone rubber is
Broadly speaking, they can be divided into electrifiable rubber, which is a solid composition consisting of a gel-like base polymer with a relatively high degree of polymerization and an inorganic filler, which is crosslinked and cured with an organic peroxide, etc., to obtain a rubber-like elastic body; There is a liquid rubber that uses dammer as a liquid base with a high degree of polymerization, and is cured by the crosslinking mechanism of @h. Due to its excellent mechanical properties, Tupurugo is commonly used as press-molded and extrusion-molded products. However, the molding process requires a factory for bulk kneading and dispensing, and it is desired to simplify such factories. In addition, since curing requires considerable temperature and time, it is not a good idea from the point of view of energy efficiency.On the other hand, among liquid rubbers, the addition reaction between the vinyl group bonded to the silicon atom and the metallurgy is used. The material is fluid before hardening, and it hardens with short heating to give a rubber-like elastic body.No by-products are generated during this process, so it is suitable for continuous production and widely used, mainly in the electrical and electronic industries. However, the mechanical strength of the rubber after curing was inferior to that of hardened rubber, and it was not used for molding purposes. .

In recent years, large quantities of KI have been developed for such additive-type liquid go^.
A filler with a highly KI&m surface has been developed, which is advantageous for increasing mechanical strength because the apparent viscosity of the system does not increase excessively even after KJ. By using a scissor-like powder in combination with dPt, it is possible to impart mechanical strength comparable to that of Tana Rubble Vv'': I-Ngo AK to the desiccated crystals of liquid rubber, and improve the fluidity. It has become possible to easily obtain molded products in a short time by injection molding or the like using a certain mm-sized silicone rubber.

In order to make the molded product as green as clay by injection molding, one of the necessary conditions is that the hardened molded product can be easily removed from the gold layer. However, the above-mentioned attachment J
When EIII liquid rubber is injection molded, it peels off as a gold layer! ! Even when using kK superior or Shimumetsu gokinho, the molded products tend to stick to gold 11iK during heat molding, making it difficult to take out the molded products, which hinders productivity.

The inventors of the present invention conducted extensive research to improve the adhesion of such molded products, and found that polyorganohide was the cause of the adhesion! The present invention has been made based on the discovery that there is a low molecular weight component present in quinane, and that its removal can defeat the purpose.

(4) A vinyl group containing at least four vinyl groups bonded to silicon atoms in one molecule.

俤) One hydrogen atom bonded to a silicon atom is present at f3/ in polyorganic tube 4V-diene V1M, which has an average of at least ihs* in one molecule, and the vapor pressure at 150°C is 1.
0 torr or less, an amount in which the number of hydrogen atoms bonded to silicon atoms per 1 vinyl group bonded to silicon atom of (A) is O, S ~ 10@, and (beak self-extra or A curable composition containing 0.2 to 10 ppm of platinum as an elemental platinum compound is heated to 80°C or higher in a forming gold layer to produce a molded product that is easy to peel off from the mold material. This invention relates to a molding method for obtaining.

The component (A) used in the zero release is a base poly! of addition type silicone rubber. - used as an organic group bonded to a silicon atom, in which at least two vinyl groups bonded to a silicon atom must be present in one molecule in order to form a network structure latently through an addition reaction. is a methyl group, an ethyl group, a pubyl group, a butyl group,
Aryl groups such as tr group, aPV group, otachij&- group, decyl-dodecyl group; aryl group such as phenyl group;
An aralkyl group such as a pyru group; a methyl group, a methyl group, or a pyru group. -cyanoethyl group, ink, s,
Substituted hydrocarbon groups such as s->11fluorocarbon groups are examples, but methyl groups are preferred due to ease of attack and balance of properties such as heat resistance, mechanical strength, and fluidity before curing. is the most preferable, and in particular when heat resistance, cold resistance, or radiation resistance is desired, it is preferable to use a fumeyl group in combination.
The above-mentioned vw unit and v unit which meets the vinyl group may be at the end or middle part of the molecular chain, but in order to increase the mechanical strength of the molded product after curing, the end part is preferable.

Although the degree of polymerization is not very noticeable, in order to form a molded product or a rubber-like elastic body after curing, the degree of polymerization is preferably 1@O or more. In order to maintain a convenient and appropriate fluidity and also obtain the mechanical strength necessary for a weiliao crystal, it is recommended that the degree of polymerization is between !OO and LOoo, especially for the mechanical strength of the coating layer after curing. In order to increase the strength, 2 to 50% by weight of the ((trans)component) is composed of a scissor-shaped polyol β-nosilokinane (T) consisting of 1.reO units and gto, units, or further consisting of KR,reO units. The wing is composed of one predominant hydrogen group, at least two vinyl groups in one molecule, and the remainder is a vinyl group bonded to the silicon atom of the sheexane unit at the end of the molecule. It is preferably a mixture with a linear polydiorganosilnan.

The component used in the present invention acts as a bombardment agent for the component (M), and in order to form a network structure, there must be an average of at least 5 hydrogen atoms bonded to silicon atoms in one molecule. , the organic group bonded to the silicon atom is exemplified by the l [s shown in ~, but for the same reason as mentioned for component (A), a methyl group is preferable. is not specified in 41, but since it is difficult to synthesize those in which two or more hydrogen atoms are bonded to the same silicon atom, it is preferable that the silokinane unit consists of black or larger silokinane units. It can be either circular or branched.

The content of the hydrogen component is (0.5 to 10, preferably 1 to S, hydrogen atoms bonded to the silicon atom of the - component, per one aakj bonded to the silicon atom of the Shu component).
There is a quantity t called iBK.

The component ((j) used in invention 11 is a catalyst for providing a rubber-like elastic body through the addition reaction of the ((conversion)) component and the component (1).The component (C) is platinum black; KII-carrying compounds, platinum tetrachloride, chloride and its alkali metal salts, alfur modified products, platinum-oletuin complex, mukogane-bielsi quinane complex, self-hostuin complex, platinum-kasanu 7 IF anchors are exemplified, but the solubility in the ((trans)component and
From the viewpoint of properties, alcohol-modified chloride-olefin complexes, self-extra-vitamin luci-quina complexes, platinum-umbrella monoliths, platinum-hostuite complexes, etc. are preferable. ,(mu),(The amount of platinum element is 0.2 to 200 pν, preferably 1 to 100 pν, in terms of the amount of platinum element compared to the accounting amount of the hardening components. If it is less than 0.2 ppm, the curing rate will be low. If it exceeds 1oopp■, it will harden too quickly and impair the workability of the ship after being mixed together.
/r.

The characteristic feature of the footwear of the present invention is that (15
The vapor pressure in IO'CK is controlled to be less than 1 Ot@rr, preferably less than 10 torr, and thereby the peelability of the footwear from the base material after curing can be significantly improved.

If a volatile positive organoid dienean is present in the hardening lIl in an amount such that the vapor pressure at l5Otk of the ml component exceeds s g torr, it will affect the delamination property of the molded product. lower.

In addition, in order to obtain a molded article with good delamination properties, which is the object of the present invention, as the component (1), 1t (o town) - 10,7° units and iio units, or these units and (0 rin ,)
, gto unit, OHs 8i0s/z unit, and as mentioned above, K111 pressure is maintained (
Controlled branched polyorganohydrogenization
It is preferable to use a silicon atom having a hydrogen atom clamped to a silicon atom.If an iris (am,) aiO unit exists as a t unit in W, the releasability of the coating layer will be reduced. Calcium-like organoid ■genshi■ medium 3'#) 2g
The viscosity at 'eK is preferably in the range of 20 to 1 #OOOoP.

2 Oor In the unpurified state, the vapor pressure at ISO'CK is s
Anything exceeding o tOrr and exceeding 1,000 or is difficult to threaten.

In order to increase the mechanical strength of the molded product, the composition used in this experiment contains an inorganic filler Jj#l. Examples of the transverse filler include al-predominant silica, precipitated silicon ν★, silica aerogel, porcelain vTI, reinforcing material T14#l such as porcelain titanium oxide, crushed quartz, diatomaceous earth, and albinosilicic acid. , asbestos, mold II! Squid, Akisu, ingredient zinc,
Examples include non-reinforcing fillers such as calcium oxide containing iron oxide; In addition, in order to prolong the curing time of the composition used in the present invention at a moderate temperature, acetylene compounds, diallyl maleate, triallyl isocyanurate), JL) sil compounds, etc. may be used. Additionally, an addition reaction inhibitor may be added. That peak?
Pigments, pigments, etc. may be added depending on the WK.

The composition used for Honjitsu@ usually contains (1) component and (0
) The ingredients should be separated and stored before use immediately before use.
, (1)% (0) of the black ink components are uniformly incubated, but all the components may be stored in the same container in the presence of a reaction inhibitor.

(1) Poda organo with low vapor pressure as a component
It is more preferable to use an hydrogen atom having hydrogen atoms bonded to a silicon atom and having only 1 (oi, ) and 01/ units as y units under these conditions. By using a scissor-shaped borishing agent, it is possible to further transform the layered properties of the hardened crystal from lI#.

In the method of the present invention, the composition obtained by controlling the vapor pressure of the K(1) component at 150°C to 50 tOrr or less is heated to 80°C or higher, preferably 15 tOrr or higher.
A molded article is obtained by molding and curing at 0°C or higher. Injection molding is particularly suitable for increasing the productivity of the molding process, and in this injection molding ratio, unless the composition of the present invention is used, the adhesion to the metal is remarkable, so the method of the present invention is suitable. The effect is the original work.

According to the method of the present invention, a molded article without adhesiveness can be obtained,
Production efficiency increases significantly. Therefore, the method of the present invention can be advantageously used in the preparation of various rubber parts for the electrical/electronic industry, the automobile industry, and the like.

Hereinafter, the present invention will be explained by way of examples. In the reference examples and the discussion, all parts represent parts by weight, and all physical property values such as viscosity are values of 25t.

Reference example 1 Experimental vehicle 100 parts of dimethyl chlorotaf and 218 parts of orthoethyl silicate
100 parts of toluene Kfa was dissolved, and the reaction temperature was 50°C.
400 while adjusting the dropping speed to 11 to avoid exceeding 400.
Hydrolysis and condensation were carried out by adding the solution dropwise to a portion of water and continuing stirring for an additional 10 minutes. After leaving to stand and separating the aqueous layer, the organic layer was washed with water until no hydrochloric acid was detected, then low-boiling components such as toluene were distilled off, and the mixture was further stirred and heated to 150°C for 2 hours. By keeping the remaining silanol groups condensed and the resulting water distilled off, 18
While heating and stirring for 2 hours at 0°C, remove low-boiling components, cool, dehydrate with anhydrous sodium sulfate, and 18
One part of polymethylhydrogen tyI was obtained.

Experiment 1 100 parts of each of the polymethyl hydride a diene salts thus obtained! was heated under reduced pressure under the conditions shown in Table 1 to remove low boiling point components to obtain polymethylhydride diene siloxanes 1 to y. The viscosity and 81-limb association rate of these polymethyl hydrochef VQ xane are shown in Table 1.

Table 1 Reference Example 2 100 parts of dimethylchlorosilane, 7 parts of trimethylchlorosilane, and 21 parts of orthoethyl silicate were mixed with 1 part of toluene.
701111C was dissolved and subjected to hydrolysis, condensation, dehydration and filtration in the same manner as in the experiment of Reference Example 1 to obtain 77145 parts of polymethylhydride. Next, add 100 parts of this polymethyl hydroxide to 10 parts.
After heating under reduced pressure at 160°C for 2 hours to remove low boiling point components, 84 parts of polymethylhydrodiene siloxane l was obtained. Viscosity and Jli-H content of these polymethylhydrodiene siloxane The rate is 1 as shown in Table 2.

Table 2 Reference Examples 7279 parts of black trimethylchloro, 84 parts of dimethyldichloride Vx11, 107 parts of methyldichloride, and 70 parts of toluene were added dropwise to 210g of water while adjusting the dropping rate so that the reaction temperature did not exceed 50°C. Then, in the same manner as in the experiment of Reference Example 1, 102 parts of polymethyl hydride quinane was obtained. Next, 10 ol of this methyl hydrogen hydroxide was heated at 10 torr and 1
The mixture was heated under reduced pressure at 40° C. for 2 hours to remove low-boiling components, and 8 parts of polymethylhydrodiene siloxane were obtained. The viscosity and content of these polymethylhydrogensiloxanes are shown in Table 5.

Black Table Example 1 Polydimethylsiloxane quinane 1 having a viscosity of 12*Oo O@P, with both ends blocked with vinyldimethylsiloxane units
00 parts, polymethylhydrodienesiloxane shown in Table 4, s-i thyl-1-butyne-ink-ol 0.04
part, 1% by weight of isopropanol 9
Samples 11-14 were opened with 0.2% Icfj & gold.

However, Samples 14 to 16 are comparative examples.

Each of these samples was heated to E1m under reduced pressure and forged at 25 cm.
It is placed in a gold plate with a chromium-plated surface, which has a width of 60 mm and a depth of 6 mm, and is heated in a heating furnace at 200°C for 10 minutes to obtain a rubber-like elastic body. When the samples were extracted using , the results shown in Table 4 were obtained.

Table 4 Example 2 Polydimethylsilicone w+ty8 with a viscosity of 120,0000 F, with both ends blocked by Bierdimethylsilicone W1 lifenan units
s part, (ox,), gio,, unit 43%, and 0. Unit 50+y%, (oiilX"t-011)Ii
15 parts of a branched polymethylvinylsiloxane containing 7 parts and % of O units was treated with methylhydride-rich quinane shown in Table 5, and the surface was treated with methyldisilazane with a specific surface area of 200"/I. 16 parts of quality silica, 15 parts of crushed quartz with an average particle size of 5JI, 5-methyl-1-butyne-
Samples 21 to 26 were prepared by uniformly mixing O-ol O, OS part, and 0.05 part of a platinum-Biersilo naan complex containing 1.5% by weight of platinum atoms. Tasoshi, samples 24-24
is comparative example material. After degassing each of these samples under reduced pressure, they were press-molded into a sheet of 100 m x 10 mm and 2 mm thick using a metal plated on one surface, and then removed using a spatula. I left the castle. In addition, the same defoamed sample was injected at a pressure of 1.5 tons into 20 cylindrical specimens with a diameter of 10-1 and a height of 2゜, the surface of which was chromium plated, using an injection molding machine. It was cured by heating at ℃ for 40 seconds, and was forcibly removed using a knock bottle. The release properties of the above press-molded sheets and injection-molded specimens from the gold layer were as shown in Table 5. In addition, the physical properties of the sheet obtained from sample 21, Jxs, are 6
When measured by so1, the hardness was 49 and the tensile strength was 8.
2 humiliation t/cd, growth was 420%.

Table 5: 50 parts of a boridiorganosinoxane having a viscosity of 20eOOOOoP, both ends of which are closed with vinyldimethylsiloxy units, and consisting of 6 mol% diphenylsiloxy units and 94 mol% dimethylsiloxy units. The polyorganohydrogen quinane shown in the table, 10 parts of A1M silica with a specific surface area of 200 m /I surface-treated with polydimethylsiloxane, and 8 parts of crushed quartz with an average particle size of 5 μm were uniformly divided. Each compound was obtained. Separately, part of the above-mentioned polyorganosytetraquinane SO, 610 parts of the above-mentioned amorphous silica, I
11 parts of crushed quartz I, and 0.0 parts of the platinum catalyst used in Example 2.
One part was mixed uniformly to obtain a catalyst-containing compound. The above-mentioned compounds containing different polyorganohydrodiene silokinanes and the catalyst-containing compound were each bubbled under reduced pressure and sent to the state station using a metering pump to mix uniformly, and samples 51 to 54 were prepared. Samples 3s to 34 are comparative example materials. When these samples were investigated for delamination properties in the same manner as the injection molding of Example 2, the results shown in Table 6 were obtained.

Table 6 Selling Agent Furutani

Claims (1)

[Scope of Claims] L(AJ) A vinyl group-containing polyorganosynan in which at least two vinyl groups bonded to a silicon atom exist in one molecule, and (1) a hydrogen atom bonded to a silicon atom exists in one molecule. The vapor pressure at Is@'CK in polyorganohide resin W containing at least three polyorganohide molecules on average is s
The vinyl 1111 bonded to the silicon atom of the polyorgano V was controlled to less than 0 torr.
, the number of hydrogen atoms bonded to silicon atoms is 0.
5 to 1011, and (as platinum element (mu) of 11 self-extension or self-association compound)
, a molding method that involves thermoforming a hardening composition consisting of 0.2 to HOOppm of Atonement Gold in a mold for a temperature of more than Km to obtain a certain Liao crystal. t. The method according to claim 1, wherein the composition further comprises an inorganic filler. 5. The method according to claim 1, wherein the composition further comprises a reaction inhibitor.
111jl I term ff1 le no method. 4 Polyorganohydrodiene siloxane (dark blue is 15
111. The method according to claim 111, wherein the vapor pressure at 0° C. is controlled to 10 torr or less. & Polyorganohydrodiene siloxane (B) is I
(01,), 110,7. Consisting of units and 8tO, units, or those units and (01!,), 81◎
, /- position, (ai,), sio□ unit, CHs 1iO
s/1 unit, or one or more types of unit! 1. The method described in paragraph 1. 4. The method according to claim 1, wherein the molding is injection molding.