JP2018053106A - Organosiloxane composition, cured article, flexible low attenuation sheet, vibration power generation module, flexible display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide novel polyorganosiloxane providing a cured article excellent in flexibility, low attenuation property and high restoration property.SOLUTION: There is provided an organosiloxane composition containing (A) organosiloxane represented by an average composition formula (1):RRSiO, where a is 1.8 to 2.1, b is 0.0002 to 0.1, 3 to 45 mol% is a phenyl group, 97 to 55 mol% is one or more kind selected from a methyl group, an ethyl group or a trifluoropropyl group in R, Ris an alkenyl group, and having average polymerization degree of 20 to 400, (B) organohydrogensiloxane having at least 2 hydrogen atoms directly binding a silicon atom in a molecule and average polymerization degree of at least 4 and (C) a catalyst for addition curing.SELECTED DRAWING: None

Description

  The present invention relates to an organosiloxane composition that gives a cured product that is transparent, flexible, and has a low damping property, the cured product, a flexible low-damping sheet made of the cured product, and a vibration power generation module and a flexible that include the cured product as members. Regarding display.

  A vibration generator is a generator with a power generation element that converts the displacement of the vibration surface into electricity. Various methods are known, but the greater the vibration displacement, the greater the amount of power generated. It is necessary to communicate well to the power generation element. However, when the vibration is attenuated by the members around the power generation element, the power generation efficiency is reduced.

  For this reason, members around the power generation element are usually made of a low-damping material, and it is generally assumed that a metal or resin having a high elastic modulus is used. However, in consideration of use in an environment with a large temperature change from low temperature to high temperature or in a high humidity situation, the power generation element should be sealed with some material. In particular, a device that can be sealed without hindering deformation of the power generation element will be required.

  By the way, research and development of vibration power generation using an organic polymer material has been actively conducted. For example, a material molded into a sheet has flexibility and can be used by being wound around a cylindrical article. In addition, it is assumed to be used in applications that are difficult with vibration power generation using non-organic materials such as members that require stretchability.

Patent Document 1 discloses a vibration power generation device using an organic polymer material as a power generation element. Although the principle is unclear, when an elastic body such as an elastomer is stacked on the top and bottom of a sheet-shaped power generation element, It is said that the amount of power generation can be obtained. However, Patent Document 1 does not clearly describe the detailed composition and performance of the elastic body. Therefore, if a displacement-releasing material is used as such an elastic body, the amount of power generation is expected to decrease. Therefore, it is considered that an elastic body combined with the power generation element needs to have a low attenuation.

  Moreover, in a flexible display, a component member is required to be flexible in order to ensure free deformation. In addition, a highly transparent pressure-sensitive adhesive or adhesive is used for adhesion between members in order to improve visibility. These materials are required to have high resilience so that when the stress is removed after deformation, the material returns to its original shape in a short time.

  From the above, in this field, development of a material having both flexibility, low attenuation and high resilience is desired, but there are few examples, and those shown in Patent Documents 2 to 5 within the scope of knowledge of the present applicant. Limited to. These materials are cationic curable resin compositions containing an epoxy compound or an oxetane compound and a cationic polymerization initiator, and the cured product is said to have a low elastic modulus at room temperature and a low damping property. Since the temperature dependency is large, it is hard at −20 ° C., and the damping property is high, the use environment is limited.

  By the way, by controlling the structure of polyorganosiloxane, it is known to have a wide range of shapes from liquids typified by silicone oils to gels, rubbers, and even hard resins used in potting agents. Yes. In addition, due to the high chemical stability derived from the polyorganosiloxane and its structure, the change in characteristics from a low temperature to a high temperature is small, and the heat resistance and weather resistance are also excellent. Therefore, rubber-like polyorganosiloxane can be expected as a material having both flexibility, low attenuation, and high resilience.

  The rubber-like polyorganosiloxane is generally a straight-chain organosiloxane having functional groups at both ends and cured with a crosslinking agent. In addition, as a means of imparting flexibility, non-reactive corn oil can be added, the number of crosslinking points can be reduced, or the amount of crosslinking agent used can be adjusted so that only one end of the linear organosiloxane reacts. The method of doing is mentioned. And any method can introduce the free organosiloxane chain | strand which is restrained only at one terminal end to the hardened | cured material obtained at most, Therefore The hardened | cured material whole becomes soft, but attenuation property also becomes high simultaneously.

JP 2013-099130 A JP 2003-313271 A JP 2005-120192 A International Publication WO2005037876 JP 2010-132918 A

  This invention makes it a subject to provide the novel polyorganosiloxane which gives the hardened | cured material which is excellent in a softness | flexibility, a low damping property, and high restoring property.

  As a result of intensive studies, the inventor includes an organosiloxane containing an alkenyl group and a predetermined amount of phenyl group in one molecule, an organohydrogensiloxane having a predetermined number of hydrosilyl groups (SiH), and an addition curing catalyst. It has been found that the above problems can be solved by the composition. That is, the present invention relates to the following organosiloxane composition, cured product, flexible low-damping sheet, vibration power generation module, and flexible display.

1. (A) Average composition formula (1): R ¹ _a R ² _b SiO _{(4-ab) / 2} (In the formula (1), a is 1.8 or more and 2.1 or less, and b is 0.00. 0002 or more and 0.1 or less, 3 to 45 mol% of R ¹ is a phenyl group, and 97 to 55 mol% is at least one selected from the group consisting of a methyl group, an ethyl group, and a trifluoropropyl group. , R ² is represented by an alkenyl group.), and an average degree of polymerization and organosiloxanes 20 to 400, having at least two hydrogen atoms bonded directly to silicon atoms in one molecule (B), An organosiloxane composition comprising an organohydrogensiloxane having an average degree of polymerization of at least 4 and (C) an addition curing catalyst.

2. The organosiloxane composition according to Item 1, wherein the hydrosilyl group of the component (B) is 0.35 or more and 1.5 or less per alkenyl group of the component (A).

3. A cured product of the organosiloxane composition of any one of Items 1 or 2.

Curing according to Item 3, wherein shear storage modulus G ′ at 4.25 ° C. and 10 Hz is 2 × 10 ⁵ Pa or less, and shear storage modulus G ′ at −40 ° C. and 10 Hz is 4 × 10 ⁵ Pa or less. object.

5. Hardened | cured material of said term 3 or 4 whose loss tangent tan-delta of 25 degreeC and 10 Hz is 0.3 or less.

7). The flexible low attenuation sheet which consists of hardened | cured material in any one of said item 3-5.

8). A vibration power generation module sealed with the cured product according to any one of Items 3 to 5.

9. 8. A vibration power generation module obtained by laminating the flexible low-damping sheet according to item 7 and a piezoelectric polymer sheet.

10. The flexible display containing the adhesive member which consists of hardened | cured material in any one of said 3-5.

  According to the organosiloxane composition of the present invention, a cured product having excellent flexibility, low attenuation, and high restorability can be obtained. Since the cured product is not only soft and easily deformed, but also does not relax the stress after deformation and easily transmits it, it is useful as a vibration power generation member, an adhesive for flexible displays, and the like.

  The organosiloxane composition of the present invention comprises a predetermined (A) organosiloxane (hereinafter referred to as component (A)), a predetermined (B) organohydrogensiloxane (hereinafter referred to as component (B)), and (C) for addition curing. A cured product containing a catalyst (hereinafter referred to as component (C)) is excellent in flexibility, low attenuation and high resilience.

The component (A) is represented by the average composition formula (1): R ¹ _a R ² _b SiO _{(4-ab) / 2} . In the formula, a is 1.8 or more and 2.1 or less, b is 0.0002 or more and 0.1 or less, 3 to 45 mol% of R ¹ is a phenyl group and 97 to 55% is a methyl group, It is at least one selected from the group consisting of an ethyl group and a trifluoropropyl group, and R ² is an alkenyl group. ) And an average degree of polymerization of 20 or more and 400 or less can be used without particular limitation.

  When a is less than 1.8, the branched structure of the component (A) is relatively increased, and the cured product tends to be too hard. When a exceeds 2.1, it becomes difficult to increase the average degree of polymerization of the component (A), and the cured product tends to be hard. From this viewpoint, a is preferably 1.9 or more and 2.0 or less.

  When b is less than 0.0002, the number of alkenyl groups in the component (A) becomes small, and the curing reaction of the composition according to the present invention tends not to proceed. On the other hand, if it exceeds 0.1, the alkenyl group becomes excessive and the flexibility of the cured product tends to be impaired. From this viewpoint, b is preferably 0.001 or more and 0.05 or less.

R ¹ is characterized in that 3 to 45 mol% of all of them are phenyl groups, and if it is less than 3 mol%, the attenuation of the cured product tends to be high. Moreover, when it exceeds 45 mol%, it exists in the tendency for the softness | flexibility of hardened | cured material to be impaired. From this viewpoint, the phenyl group in all R ¹ is preferably about 3 to 45 mol%.

R ¹ is at least one selected from the group consisting of a methyl group, an ethyl group, and a trifluoropropyl group, with the remaining 97-55 mol% being the remainder. If these are over 97 mol%, the attenuation of the cured product tends to be high, and if it is less than 55 mol%, the flexibility of the cured product tends to be impaired. From this viewpoint, the balance is preferably about 55 to 97 mol%.

R ² is an alkenyl group, and specific examples include a vinyl group, a propenyl group, an allyl group, and a butenyl group.

  The average degree of polymerization of the component (A) is 20 or more and 400 or less, and if it is less than 20, the hardness of the cured product tends to be too high. Moreover, when it exceeds 400, it exists in the tendency for the attenuation | damping property of hardened | cured material to become high. From this viewpoint, the average degree of polymerization is preferably 100 or more and 300 or less.

  As the component (B), various known materials are used without particular limitation as long as they are organohydrogensiloxanes having at least two hydrogen atoms directly bonded to silicon atoms in one molecule and an average degree of polymerization of at least 4. it can. By setting the hydrogen atom to 2 or more, the component (B) is efficiently incorporated into the cured product, and the attenuation is reduced. From this viewpoint, the average degree of polymerization is 4 or more and 400 or less, more preferably 10 or more and 100 or less. Examples of other functional groups in the component (B) include a methyl group, an ethyl group, a propyl group, a trifluoropropyl group, a phenyl group, and a tolyl group.

  Although the usage-amount of (A) component and (B) component is not specifically limited, Usually, the molar ratio of the amount of alkenyl groups of (A) component and the amount of silicon atom bond hydrogen groups (SiH) in (B) component [SiH / Alkenyl group] is preferably in the range of about 0.35 to 1.5. By setting it as 0.35 or more, there is a tendency that unreacted alkenyl groups are reduced and the attenuation of the cured product is lowered. Moreover, by setting it as 1.5 or less, it is in the tendency for the unreacted SiH group to decrease and to be compatible with the softness | flexibility and low attenuation | damping property of hardened | cured material.

Component (C) is a catalyst for the addition reaction between the silicon atom-bonded alkenyl group in component (A) and the silicon atom-bonded hydrogen atom in component (B), that is, a hydrosilylation reaction. The catalyst can be used without any particular limitation. Specifically, platinum-based catalysts such as fine platinum powder, platinum black, chloroplatinic acid, platinum tetrachloride, alcohol-modified chloroplatinic acid, platinum olefin complexes, platinum alkenylsiloxane complexes, platinum carbonyl complexes; [Rh ( O ₂ CCH ₃ ) ₂ ] ₂ , Rh (O ₂ CCH ₃ ) ₃ , Rh ₂ (C ₈ H ₁₅ O ₂ ) ₄ , Rh (C ₅ H ₇ O ₂ ) ₃ , Rh (C ₅ H ₇ O ₂ ) _{(CO) 2, Rh (CO} ) [Ph 3 P] (C 5 H 7 O 2), RhX 3 [(R 3) 2 S] 3, (R 4 3 P) 2 Rh (CO) X, (R ⁴ ₃ P) ₂ Rh (CO) H, Rh ₂ X ₂ Y ₄ , Rh [O (CO) R ³ ] _3-c (OH) _c , or H _d Rh _p (En) _q Cl _z Rhodium catalyst (wherein X is a hydrogen atom, a chlorine atom, a bromine atom or an iodine atom) Y is an alkyl group such as a methyl group or an ethyl group, CO, C ₈ H ₁₄ , or 0.5C ₈ H ₁₂ , R ³ is an alkyl group, a cycloalkyl group, or an aryl group, and R ⁴ is An alkyl group, an aryl group, an alkyloxy group, or an aryloxy group, En is an olefin, c is 0 or 1, d is 0 or 1, p is 1 or 2, and q is 1 an to 4 integer, z is 2, 3, or 4); _{wherein:. Ir (OOCCH 3) 3} , Ir (C 5 H 7 O 2) 3, [Ir (Z) (En) 2] ₂ or [Ir (Z) (Dien)] An iridium-based catalyst represented by ₂ (wherein Z is a chlorine atom, bromine atom, iodine atom, or alkoxy group, En is an olefin, and Dien is a cyclohexane) Octadiene)).

  As the component (C), a platinum-based catalyst is particularly preferable, and a platinum-alkenylsiloxane complex is more preferable because it has high curability and exhibits curability even at low temperatures. Examples of the alkenylsiloxane include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, Examples include alkenyl siloxanes in which a part of methyl groups of these alkenyl siloxanes are substituted with groups such as ethyl groups and phenyl groups, and alkenyl siloxanes in which vinyl groups of these alkenyl siloxanes are substituted with groups such as allyl groups and hexenyl groups. 1,3-divinyl-1,1,3,3-tetramethyldisiloxane is preferable in terms of the stability of the platinum-alkenylsiloxane complex. In order to improve the stability of the complex, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3-diallyl-1,1,3,3-tetramethyldisiloxane, , 3-Divinyl-1,3-dimethyl-1,3-diphenyldisiloxane, 1,3-divinyl-1,1,3,3-tetraphenyldisiloxane, 1,3,5,7-tetramethyl-1 , 3,5,7-tetravinylcyclotetrasiloxane and other alkenylsiloxanes and dimethylsiloxane oligomers and other organosiloxane oligomers can be used in combination, and alkenylsiloxanes are particularly preferred.

  The amount of component (C) used is not particularly limited as long as it is a so-called catalyst amount, but is usually about 0.00001 to 0.05 parts by mass in terms of metal atom, preferably 100 parts by mass of component (A), preferably May be about 0.0002 to 0.01 parts by mass.

  The organosiloxane composition of the present invention may contain an organic solvent (hereinafter referred to as component (D)) as necessary. Specific examples include toluene, xylene, benzene, n-hexane, n-heptane, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate and the like, and two or more kinds can be used in combination. Among these, toluene is preferable because it can be removed by heating at about 100 ° C.

  In the organosiloxane composition of the present invention, as additives, for example, curing retarder, inorganic phosphor, anti-aging agent, radical inhibitor, ultraviolet absorber, adhesion improver, flame retardant, surfactant, storage stability Improving agent, antiozonant, light stabilizer, thickener, plasticizer, coupling agent, antioxidant, thermal stabilizer, conductivity imparting agent, antistatic agent, radiation blocking agent, nucleating agent, phosphorus-based excess An oxide decomposing agent, a lubricant, a pigment, a metal deactivator, a physical property modifier, an organic solvent, an inorganic filler, and the like can be blended. For example, when an inorganic filler is blended, the refractive index of the cured product and the fluidity of the composition can be adjusted, and the strength thereof can be improved. The kind of the inorganic filler is not limited, and examples thereof include alumina, aluminum hydroxide, fused silica, crystalline silica, ultrafine amorphous silica, hydrophobic ultrafine silica, calcium carbonate, and barium sulfate.

  The organosiloxane composition of the present invention can be prepared by mixing the component (A), the component (B) and the component (C), and optionally the component (D) and / or the additive in any order. The mixing means is not particularly limited.

  The cured product of the present invention is obtained by curing the organosiloxane composition of the present invention. Curing conditions are not particularly limited, and may usually be about 20 minutes to 12 hours at 20 to 180 ° C.

  The cured product of the present invention can be specified by storage elastic modulus G ′, loss tangent tan, and Young's modulus. Each means hardness, damping, and flexibility.

The shear storage modulus G ′ of the cured product of the present invention is such that the shear storage modulus G ′ at 25 ° C. and 10 Hz is 1 × 10 ³ Pa or more and 2 × 10 ⁵ Pa or less, and shear storage at −40 ° C. and 10 Hz. The elastic modulus G ′ is 1 × 10 ³ Pa or more and 4 × 10 ⁵ Pa or less.

  The loss tangent tan of the cured product of the present invention is the ratio of the shear storage elastic modulus (G ′) to the shear loss elastic modulus (G ′ ″), and is represented by the loss tangent (G ′ / G ′ ′). This value is usually 0.3 or less, preferably 0.2 or less, more preferably 0.15 or less. The lower limit value is essentially 0, but substantially 0.01.

  The flexible low attenuation sheet of the present invention is obtained by molding the cured product of the present invention into a sheet shape. Specifically, the composition according to the present invention is applied on a plastic film such as polyethylene terephthalate (PET), heated and cured, and then peeled to obtain a sheet-like cured product. At that time, if the upper surface of the cured coating film is covered with a plastic film, a sheet with less unevenness on both sides can be obtained.

  The vibration power generation module of the present invention is an article including the cured product of the present invention as a member. Generally, in vibration power generation, electrodes for taking out generated electricity are formed above and below a piezoelectric element. The outside is covered with a flexible piezoelectric polymer sheet from above and below to protect the elements and electrodes. The cured product of the present invention can be used as a sealant for the vibration power generation module or a member for laminating the piezoelectric polymer sheet. Since the cured product of the present invention has good flexibility as described above, piezoelectric elements can be laminated without any gaps. In addition, it is considered that the power generation efficiency is increased because stress due to deformation is transmitted to the piezoelectric element without being absorbed or relaxed by the cured product. The piezoelectric element and the cured product may be laminated using an adhesive, and the organosiloxane composition according to the present invention can be used as the adhesive. Moreover, as a piezoelectric polymer sheet, the sheet | seat etc. which uniaxially stretched polyvinylidene fluoride resin and poly L-lactic acid are mentioned, for example.

  The flexible display of the present invention is an article containing the cured product of the present invention as an adhesive member. The flexible display is obtained by forming an organic EL or TFT on an organic film, and these are protected by a protective layer and a barrier layer, and the cured product according to the present invention can be used as each layer. The flexible display can also be used as a touch panel by providing a touch-sensitive film sensor on the upper surface. A transparent adhesive is used for bonding the flexible display and the film sensor, and the organosiloxane composition according to the present invention can be used as the adhesive.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, the scope of the present invention is not limited by them. In each example, parts and% are based on weight unless otherwise specified.

Example 1
Polydiphenylsiloxane-polydimethylsiloxane having vinyl groups at both ends (average polymerization degree 220, phenyl group 6 mol%, methyl group 94 mol%; product name “PLY2-7560”, manufactured by NuSil Technology) (hereinafter referred to as component (A1)) ) 100 parts, methyl hydrogen polysiloxane having an average of 39 hydrogen atoms bonded directly to silicon atoms (number average molecular weight 6,000, average degree of polymerization 87; product name “XL-112”, manufactured by NuSil Technology) 1 .55 parts, platinum-divinyltetramethyldisiloxane (Pt 2.7%) (hereinafter referred to as (C1) component) 0.037 parts (10 ppm), and ethynylcyclohexanol (ECH) 0.1 part as a reaction control agent The mixture was mixed to prepare an organosiloxane composition. [SiH / alkenyl group] was 0.9.

Examples 2-5, Comparative Examples 1-5
The raw materials shown in Tables 1 and 2 were mixed in respective parts to prepare organosiloxane compositions.

(A2): Polydiphenylsiloxane-polydimethylsiloxane having vinyl groups at both ends (average polymerization degree 170, phenyl group 14 mol%, methyl group 86 mol%; product name “PLY-7666”, manufactured by NuSil Technology)
(A3): Polydiphenylsiloxane-polydimethylsiloxane having vinyl groups at both ends (average polymerization degree 20, phenyl group 36 mol%, methyl group 64 mol%; product name “PLY-7665”, manufactured by NuSil Technology)
(A4): Polydiphenylsiloxane-polydimethylsiloxane having vinyl groups at both ends (average polymerization degree 570, phenyl group 6 mol%, methyl group 94 mol%; product name “PLY3-7560”, manufactured by NuSil Technology)
(A5): Polydimethylsiloxane having vinyl groups at both ends (average polymerization degree 240, phenyl group 0 mol%, methyl group 100 mol%; product name “621V350”, manufactured by Bluestar Silicones)
(B2): Methyl hydrogen polysiloxane having an average of 6 hydrogen atoms directly bonded to silicon atoms (molecular weight 800, average polymerization degree 12; product name “XL-110”, manufactured by NuSil Technology))

  The composition according to Example 1 was poured into a Teflon (registered trademark) cup in an amount such that the thickness after curing was 3 mm, and the cured product was obtained by heating at 105 ° C. for 30 minutes and then at 150 ° C. for 30 minutes. Cured products were obtained in the same manner for the compositions of other examples and comparative examples (excluding comparative example 1). The composition of Comparative Example 1 did not cure.

Comparative Example 6
An addition curing type silicone gel “TSE3070” (manufactured by Momentive) containing no phenyl group in the molecule was cured in the same manner as above to obtain a cured product having a thickness of 3 mm.

<Measurement of shear storage modulus (G ′) and tan δ>
The dynamic viscoelasticity of the cured product according to Example 1 was measured using a rheometer (manufactured by HAAKE, MARS) under the conditions of a degree of 25 ° C., a frequency of 10 Hz, and a displacement γ = 0.01, and a shear storage modulus (G '), Tan δ was determined.

Through Tables 4 to 6, it can be seen that the cured products according to the examples have both low elasticity and low tan δ, so that flexibility and low damping are compatible.

Claims (9)

(A) Average composition formula (1): R ¹ _a R ² _b SiO _{(4-ab) / 2} (In the formula (1), a is 1.8 or more and 2.1 or less, and b is 0.00. 0002 or more and 0.1 or less, 3 to 45 mol% of R ¹ is a phenyl group, and 97 to 55 mol% is at least one selected from the group consisting of a methyl group, an ethyl group and a trifluoropropyl group. R ² is an alkenyl group), and an average degree of polymerization of 20 to 400,
(B) an organohydrogensiloxane having at least two hydrogen atoms bonded directly to a silicon atom in one molecule and having an average degree of polymerization of at least 4;
(C) an addition curing catalyst;
An organosiloxane composition comprising: The organosiloxane composition according to claim 1, wherein the hydrosilyl group of component (B) is 0.35 or more and 1.5 or less per one alkenyl group of component (A). Hardened | cured material of the organosiloxane composition in any one of Claim 1 or 2. The cured product according to claim 3, wherein the shear storage modulus G ′ at 25 ° C. and 10 Hz is 2 × 10 ⁵ Pa or less, and the shear storage modulus G ′ at −40 ° C. and 10 Hz is 4 × 10 ⁵ Pa or less. The hardened | cured material of Claim 3 or 4 whose loss tangent tan-delta of 25 degreeC and 10 Hz is 0.3 or less. A flexible low attenuation sheet made of the cured product according to claim 3. A vibration power generation module sealed with the cured product according to claim 3. A vibration power generation module formed by laminating the flexible low-damping sheet according to claim 6 and a piezoelectric polymer sheet. The flexible display containing the adhesive member which consists of hardened | cured material in any one of Claims 3-5.