JP4109027B2 - Organic-inorganic hybrid low-melting glass and method for producing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel low-melting glass having a low softening point, for example, a low-melting glass useful as an optical functional material such as an optical waveguide, and a method for producing the same.
[0002]
[Prior art]
The low melting point glass is generally a glass having a softening point of 600 ° C. or lower, and is referred to as a low melting point glass because it has a lower softening start temperature, so-called “melting point”, compared to a commercially available plate glass. . This low-melting glass has long been widely used as a sealing / sealing material, passivation glass, glaze and the like. In addition, since it can be baked at a “low temperature” that does not cause thermal decomposition of organic molecules, it can be a basic optical functional material that supports photonics by dispersing functional organic molecules in transparent glass.
[0003]
Various composition systems have been proposed for the low melting glass. For example, Sn-Pb-PFO glass developed by Tick et al. Has a glass transition point in a low temperature range of around 100 ° C. and exhibits excellent water resistance. However, most of the glass called low melting point glass has a problem from the viewpoint of environmental protection because it contains lead as a main component. In recent years, glass systems that do not contain lead have been proposed, but they contain composition factors that have safety problems such as bismuth and cadmium, and low-melting-point glasses that are environmentally friendly have been proposed. It is in a situation that can not be said. Further, in a glass composition system that does not contain lead, a glass having a transition point of around 100 ° C. is not known.
[0004]
As a low-temperature synthesis method of a glassy bulk material, there are a sol-gel method and a liquid phase reaction method. In the sol-gel method, a bulk body can be obtained by hydrolysis-dehydration condensation polymerization of a metal alkoxide, but a completely dense bulk body cannot be obtained by heat treatment at 600 ° C. or lower. On the other hand, the liquid phase reaction method has a fatal problem that the yield is low, and also uses hydrofluoric acid in the reaction system, so it generates HF with extremely high corrosiveness. In reality, it is almost impossible to produce a glassy bulk body.
[0005]
It is also considered to use silicone as an amorphous bulk material like a polymer glass. In the case of silicone, a bulk body can be obtained by entanglement of a polymer having a siloxane skeleton, or by crosslinking between polymers with a certain organic substance. The bulk material made of silicone thus obtained is characterized by being more stable at a higher temperature than plastics, but has a fundamental problem that it is inferior to a low-melting glass such as hermeticity and long-term stability.
[0006]
[Problems to be solved by the invention]
Conventional so-called low-melting glass contains lead and has a problem in terms of environmental protection. The low melting point glass not containing lead contains composition factors having safety problems such as bismuth and cadmium, and a glass having a transition point of around 100 ° C. is not known.
[0007]
For glassy bulk bodies, a complete and dense bulk body cannot be obtained by the sol-gel method. Therefore, when viewed as a practical material, insufficient strength, oxidation of introduced substances, and attack by water are serious problems. However, in the liquid phase reaction method, the yield was low, and HF was generated during the reaction, so that it was almost impossible to synthesize a glassy bulk material realistically.
[0008]
That is, a substance having a transition point near 100 ° C. or lower than 100 ° C. and having no environmental problems such as lead and bismuth is not used as a glass composition factor, hermeticity as a material, long-term stability and strength, and further attack by water There was virtually no material that could be produced.
[0009]
[Means for Solving the Problems]
The present invention does not use low melting point glass having a transition point of less than 100 ° C. as a composition factor for substances such as lead, bismuth, and cadmium that have environmental problems, and is hermetic, long-term stability and strength as a sealing material, The present invention relates to the provision of materials that can be produced without problems such as water attack.
[0010]
The present invention is an organic-inorganic hybrid low-melting glass of R ₃ SiO _0.5 —R ₂ SiO—MO—P ₂ O ₅ system obtained by heating reaction of dialkyldichlorosilane, trialkylchlorosilane, phosphoric acid and metal chloride ( Where R is a methyl group or ethyl group, and M is a divalent metal ( Sn, Zn, or Ge 2 ).
[0014]
In the present invention, the metal chloride used in the reaction is preferably a divalent metal chloride, and specifically, a chloride of Sn, Ge, and Zn is preferably used.
[0015]
A feature of the production method of the present invention is that trialkylchlorosilane R _x SiCl is used as a starting material, and the organic-inorganic hybrid low-melting glass of the present invention is synthesized and manufactured based on a new concept completely different from silicone. The
[0016]
That is, by terminating the siloxane skeleton with an organic functional group to lower the network dimension and lower the melting point of the glass itself, the physical properties are similar to those of a low melting point glass rather than a plastic.
[0017]
The organic-inorganic hybrid low-melting glass of the present invention has good airtightness when used as a sealant. Furthermore, many applications are expected as a host of a functional organic substance having optical functionality and the like.
[0019]
The characteristics of the low melting point glass and the production method obtained by the present invention are listed as follows.
-It is a uniform bulk body.
-Since the reaction system does not contain water, an anhydrous bulk can be easily obtained.
-Since it can be synthesized at low temperatures, it can contain organic dyes without decomposing them, and its solubility is high.
-The obtained amorphous bulk body has the property of glass.
-The obtained bulk body has high moldability, which is a characteristic of glass, and can be easily processed into a fiber or a thin film shape.
-Reaction products other than the target product are vaporized and released out of the system.
-Since it is formed of an oxide skeleton and an organic functional group bonded to the oxide skeleton, the controllability of physical properties by composition is higher than that of a conventional organic-inorganic composite.
-Due to the presence of the organic functional group, a large amount of functional organic substances can be introduced into the glass. Moreover, the kind of organic substance introduced by changing the kind can be selected.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
The present invention uses the following reaction when trialkylchlorosilane (R ₃ SiCl), dimethyldichlorosilane (Me ₂ SiCl ₂ ) and phosphoric acid (for example, H ₃ PO ₄ , H ₃ PO ₃ ) are used as starting materials. Based on this concept, organic-inorganic hybrid low-melting glass is formed.
P-OH + Si-Cl → Si-OP + HCl ↑
In this reaction, HCl as a reaction product is released out of the system as a gas, and thus the reaction proceeds in one direction, so that a dense bulk body is formed. Further, even if a metal chloride such as tin chloride is allowed to coexist in these systems, a dense and low melting point bulk material can be obtained. Even when other metal chlorides are used, the basic reaction mechanism is the same. Ideally, all of HCl is released out of the system as a gas, but in either case, chlorine compounds may remain as glass.
[0021]
The reaction of the organic-inorganic hybrid low-melting glass of the present invention can be synthesized at a low temperature from room temperature to 300 ° C., and the obtained glass has a low softening temperature and a high moldability (can be remelted), and is a fiber or thin film It can be easily processed into a shape, and can be a host material that disperses functional organic molecules at a low temperature that does not cause thermal decomposition of organic molecules.
[0022]
The preferred composition of the organic-inorganic hybrid low-melting glass obtained in the present invention is R ₃ SiO _0.5 —R ₂ SiO—MO—P ₂ O ₅ (where R is a methyl group or ethyl group, and M is a divalent metal). ) System organic-inorganic hybrid low melting point glass (where R is a methyl group or ethyl group, M is a divalent metal), and trialkylchlorosilane and phosphoric acid, or trialkylchlorosilane and phosphoric acid and metal chloride are water. It is manufactured by making it heat-react without using. For example, in the case of Sn-based glass, the glass is mainly composed of R ₃ SiO _0.5 —R ₂ SiO—SnO—P ₂ O ₅ , but there are three Rs (for example, methyl groups) around Si. Therefore, the bonding property as glass is lowered, and as a result, a glass having a low transition point can be obtained.
[0023]
One of the characteristics is that the reaction temperature is from room temperature to about 300 ° C., which is lower than that in the past, and the energy during bulk body synthesis can be suppressed.
[0024]
【Example】
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the following examples.
[0025]
(Example 1)
As starting materials, phosphoric acid (H ₃ PO 4), dimethyldichlorosilane (Me ₂ SiCl ₂ ), and tin chloride (SnCl ₂ ) are used. The composition of the sample was determined by setting the mixing ratio of H ₃ PO ₄ : Me ₃ SiCl: Me ₂ SiCl ₂ : SnCl ₂ to 2: 2x: 2.5x: 0.5, and x under the four conditions of 0, 0.5, 1, and 1.5 did. In a nitrogen atmosphere reactor, orthophosphoric acid was heated to 40 ° C. to make a liquid, then trialkylchlorosilane was added, and the mixture was heated and stirred for 3 hours. During this process, the temperature was gradually raised and heated to 100 ° C. At this stage tin chloride was added. This was further heated at 250 ° C. for 1 hour under a nitrogen atmosphere, and the final product, an organic-inorganic hybrid low-melting glass, was obtained as a total of 6 samples. The reason for the two-step heating reaction is to obtain a denser bulk body, and the combination of the temperature and time of the heating reaction is arbitrary.
[0026]
A production scheme of the organic-inorganic hybrid low-melting glass of the present invention is shown in FIG. FIG. 2 is a graph showing the composition dependence of the glass transition temperature of an organic-inorganic hybrid low-melting glass using tin chloride. x was examined under four conditions of 0, 0.5, 1 and 1.5.
[0027]
As shown in the graph of FIG. 2, the obtained sample exhibits various glass transition points depending on the composition and reaction time. The glass transition temperature varies depending on the composition and time from −47 to 30 ° C., and can freely change the low glass transition temperature, which is a characteristic of low-melting glass, and can also obtain a glass having an extremely low transition point. did it.
[0028]
Unlike polymer glasses, not only the network dimension but also the chemical bonding between the bulk constituent elements affects the glass transition temperature, and by selecting the organic part of the alkylchlorosilane or the metal to be added at the same time, a very wide range can be obtained. Physical property control (glass transition temperature) becomes possible.
[0029]
(Example 2)
In Example 1, the same reaction was carried out except that germanium chloride was used instead of tin chloride. As a result, a light yellow transparent plate-like final product similar to the case of tin chloride was obtained. The composition of the sample was determined by setting the mixing ratio of H ₃ PO ₄ : Me ₃ SiCl: Me ₂ SiCl ₂ : GeCl ₂ to 2: 2x: 2.5x: 0.5, and x under the four conditions of 0, 0.5, 1, and 1.5 did. Moreover, the glass transition point (Tg) of this sample shows various tendencies depending on the composition. A result is shown in FIG. 3 which is a graph which shows the composition dependence of the glass transition temperature of each organic-inorganic hybrid low melting glass which respectively used germanium chloride, aluminum chloride, and zinc chloride.
[0031]
( Example 3 ) In Example 1, the same reaction was carried out except that zinc chloride was used instead of tin chloride. As a result, a light yellow transparent plate-like final product similar to the case of tin chloride was obtained. It was. The composition of the fabricated sample was examined under four conditions where the mixing ratio of H ₃ PO ₄ : Me ₂ SiCl ₂ : ZnCl ₂ was set to 2: x: 2, and x was 0, 0.5, 1, and 1.5. The results are shown in FIG. It can be seen that the glass transition point (Tg) shows various tendencies depending on the composition.
[0032]
【The invention's effect】
The organic-inorganic hybrid low melting point glass of the present invention has characteristics that have not been achieved so far. In other words, it can be synthesized at a low temperature from room temperature to 300 ° C., has a low softening temperature and high moldability (can be remelted), can be easily processed into a fiber or thin film shape, and does not thermally decompose organic molecules. It can be a host material that disperses functional organic molecules.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram of an organic-inorganic hybrid low melting point glass reaction scheme of the present invention.
FIG. 2 is a graph showing the composition dependence of the glass transition temperature of an organic-inorganic hybrid low-melting glass using tin chloride.
FIG. 3 is a graph showing the composition dependence of the glass transition temperature of each organic-inorganic hybrid low melting glass using germanium chloride and zinc chloride , respectively.

Claims (1)

Dialkyl _{dichlorosilane, R 3 SiO 0.5 -R 2 SiO} -MO-P 2 O 5 based organic obtained by thermal reaction of trialkyl chlorosilane and phosphoric acid and metal chlorides - inorganic hybrid low-melting glass (where, R represents Methyl group or ethyl group, M is a divalent metal Sn, Zn or Ge 2 )

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