Method of preparing liquid state non-solvent silicone resin and resin formed thereby

A liquid state non-solvent silicone resin obtained from a polycondensation reaction of material (A) dimethyl poly siloxane, material (B) vinyl methyl cyclo siloxane and material (C) diphenyl dihydroxy silane, the reaction being performed at a temperature within about 140.about.180.degree. C. under the presence of an anionic polymerization catalyzer.

BACKGROUND OF THE INVENTION
 It is well known that silicone resins can be obtained from organic chloro
 silane or organic alkoxy silane by means of hydrolysis and
 polycondensation. Under the presence of a catalyzer or by means of
 heating, silicone resins can be turned to an insoluble thermosetting
 product of three-dimensional network structure. When hardened, silicone
 resins are maintained stable within a wide range of temperature, humidity
 and frequency. Because silicone resins are oxidation resistant, electric
 arc resistant, radiation resistant, weather proof, water proof, salty fog
 resistant and damp proof, they are suitable for use as a base material for
 making insulative paint, or material for molding or laminating into
 products for industrial use. Most silicone resins are polycondensed into a
 three-dimensional network structure. These resins contain a large amount
 of silanol. When these resins are added with inorganic stuffing such as
 glass fibers, quartz powder, etc., the material thus obtained can be used
 for molding into a variety of products. However, because a low molecular
 compound is released when hubbing, air bubbles exists in the molded
 product. Therefore, these silicone resins are not suitable for molding
 transparent products. Dimethyl dichloro silane, diphenyl dichloro silane,
 phenyl trichloro silane or vinyl methyl dichloro silane can used for
 making a polycondensed silicone resin that contains vinyl with little
 silanol. When the resin is heated or induced by peroxide, the double
 chains of vinyl are opened, therefore the resin is polycondensed into a
 product of three-dimensional network structure. This material does not
 release a low molecular compound when molding. However, when this resin is
 hardened, it tends to break due to the occurrence of a stress resulted
 from high shrinkage.
 SUMMARY OF THE INVENTION
 The present invention has been accomplished to provide a liquid state
 non-solvent silicone resin which eliminates the aforesaid drawbacks. The
 liquid state non-solvent silicone resin can be made into a transparent
 hard resin of high strength and low shrinkage by means of polycondensation
 or molding. The transparent hard resin thus obtained does not break, and
 has high strength and low shrinkage.
 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
 A liquid state non-solvent silicone resin made according to the present
 invention is colorless, transparent, and stable. It is comprised of:
 (A) dimethyl poly silioxane
 ##STR1##
 in which, R': methyl or vinyl; R.sup.2, R.sup.3 N R.sup.4, R.sup.5 :
 methyl, vinyl or phenyl, preferably methyl; "m" and "n": 0.about.1000.
 (B) organic cyclo siloxane
 ##STR2##
 in which, R.sup.6 and R.sup.7 : methyl, vinyl or phenyl, preferably methyl
 for R.sup.6 and phenyl for R.sup.7 ; "p": 3, 4 or 5, preferably 4. (C)
 diphenyl dihydroxy silane
 ##STR3##
 The aforesaid materials (A), (B) and (C) are commonly used materials for
 organic silicone, and can easily be obtained from the market.
 The aforesaid materials (A), (B) and (C) are prepared at
 1.about.5:1:6.about.1 by mole. Under the presence of anionic
 polymerization catalyzer through a polycondensation reaction, the
 molecules of Si-O-Si chain are re-arranged into a balanced status. The
 anionic polymerization catalyzer can be an alkali metal hydroxide such as
 KOH, NaOH, LiOH, and their reacted product with silane, such as potassium
 silane, sodium silane, lithium silane, preferably lithium silane. The
 amount of the anionic polymerization catalyzer is about 0.005.about.0.004%
 by weight of the amount of the silicone resin, preferably about
 0.01.about.0.02%. The polycondensation reaction temperature is within
 about 140.about.180.degree. C., preferably within about
 150.about.160.degree. C. The vacuum state is controlled within about 0.0
 1MPa.about.0.095MPa. The reaction time is within 1.about.3 hours.
 Reinforcing agent may be added. However, the use of reinforcing agent must
 match the liquid state non-solvent silicone resin in refractive index.
 Reinforcing agent can be obtained from white-carbon or MQ resin (silicone
 resin containing vinyl). White-carbon can be obtained by deposition or gas
 phase method. White-carbon from hydrophobic gas phase method is preferably
 accepted. The added amount of reinforcing agent is about 50.about.120% by
 weight of the amount of liquid state non-solvent silicone resin,
 preferably about 80.about.100% by weight.

EXAMPLE 1
 Put 59.2 grams poly dimethyl siloxane of trimethyl silane of viscosity
 500cp, 34.4 grams 1.3.5.7-tetra vinyl-1.3.5.7-tetra methyl-cyclo tetra
 siloxane, 21.6 grams diphenyl dihydroxyl silane and 2.3 grams diphenyl
 dihydroxy silane catalyzer (KOH content 1%) in a 250 ml three-necked flask
 which is equipped with a stirrer, a thermometer, an oil-water separator
 and a condenser, then heat the flask to 150.about.160.degree. C. when
 stirring, then release the pressure, and then remove water from the
 reacted medium. About 1.about.2 hours after reaction, the material in the
 flask becomes transparent. When no water or other low molecular substance
 is released, the reaction is stopped, and a colorless, transparent,
 viscous silicone resin is thus obtained.
 EXAMPLE II
 Add 5 grams phenyl silicone oil, 10 grams hydrophobic gas phase catalyzer
 and a small amount of platinum catalyzer to 10 grams of the aforesaid
 colorless, transparent, viscous silicone resin, then mix the mixture well,
 and then treat the mixture by hubbing at about 130.degree. for about 5
 minutes, and then heat the molded product at about 200.degree. C. for
 about 4 hours, and thus a finished product of high strength, high hardness
 and high transparency is obtained.