JP-7857431-B2 - Use of cyclodextrins as carriers for silicone materials and active substances

Inventors

• アミターバ、ミトラ
• メーガン、グートマン
• クリスチャン、ハートマン
• ベラ、ポポーバ－ゲオルギエバ

Assignees

• ワッカー ケミー アクチエンゲゼルシャフト

Dates

Publication Date

20260512

Application Date

20220425

Claims (10)

1. A curable silicone rubber composition, each comprising -20 to 99.9% by weight of a silicone matrix and -0.1 to 80% by weight of at least one cyclodextrin (CD) modified by a silylation reaction and containing a silyl group of formula (1), based on the total amount of the silicone rubber composition. -(OSi(R 1 ) 3 ) x (1) [In the formula, R1 is independently the same or different from each other, and is an alkyl group , an aryl group or an alkyl-substituted aryl group, or a carbonyl group. x is a number between 1 and 96. - 0 to 50% by weight of at least one active molecule (= guest molecule) Includes, The curable silicone rubber composition wherein the total amount of all components is always 100% by weight.
2. The curable silicone rubber composition according to claim 1, which is an addition-curable silicone composition.
3. The curable silicone rubber composition according to claim 1, wherein R1 is selected from methyl, ethyl, vinyl, and phenyl.
4. The curable silicone rubber composition according to claim 1, wherein x is a value between 1 and 30.
5. The curable silicone rubber composition according to claim 1, wherein the guest molecule is selected from the group consisting of drugs, pharmaceuticals, cosmetics or personal care or health active substances, biocides, insecticides, fungicides, herbicides, pheromones, fragrances, flavorings, pigments, pharmaceutically active compounds, natural oils or other oils, antigens, active compounds for antistatic or flame-retardant finishes, stabilizers (ultraviolet light), dyes, and odor-generating molecules, or a combination of two or more such molecules.
6. A method for producing the curable silicone rubber composition described in claim 1, comprising the step of mixing all the compounds at room temperature or by heating using standard mixing techniques.
7. A silicone product obtained by filling a mold with the curable silicone rubber composition described in claim 1, or by applying it to a surface and then curing it.
8. Use of the silicone product according to claim 7, in which an active substance is included, for controlled release, delayed release, or induced release of the active substance.
9. Use of the silicone product according to claim 8 in any one application selected from the group consisting of pharmaceutical applications, cosmetic applications, personal care applications, wellness applications, room fragrance applications, biocides, insecticides, fungicides, herbicides, and textile applications.
10. Use of the silicone product according to claim 7 for the purpose of capturing unwanted substances, in cases where it does not contain an active substance.

Description

This invention relates to cyclodextrin as part of a silicone composition, and its use for forming articles for the absorption, encapsulation, and delivery of active substances and other compounds. Examples of such articles may include transdermal patches, pressure-sensitive adhesives, medical devices, membranes, gels, clothing, or other wearable materials. Cyclodextrin is compatible with silicone matrices without the use of additional compatibilizers. This invention can be used in a variety of applications, including cosmetics, medical, home care, textiles, industrial, and others. Silicone-compatible cyclodequines can be used in applications such as controlled release, delayed or extended release, on-demand release, and triggered release of active substances. The reaction between reactive rubber or silicone rubber and modified cyclodextrin has already been described in prior art. US Patents 5,391,592 describe a silicone elastomer for contact lens applications, produced by reacting alkenyl-modified cyclodextrin (CD) with SiH-containing silicone via a hydrosilylation reaction to create a lipophilic CD-silicone polymer. This patent does not teach the encapsulation and release of active substances from the elastomer. Furthermore, the lipophilicity of CD does not necessarily mean compatibility with silicone. Therefore, forming an elastomer using only hydrophilic or lipophilic CD requires special conditions, such as the use of additional compatibility elements (e.g., solvent, high temperature). Thus, in the example of 592, toluene is used as a solvent to bring the different components (cyclodextrin and silicone) into the same phase for the hydrosilylation reaction necessary to produce the elastomer material for contact lenses. The use of an additional solvent results in additional manufacturing costs due to the required special handling, as well as environmental and health concerns. US7,235,186B2 describes the bonding of cyclodextrins to silicones by condensation reactions. However, it requires the use of specific types of cyclodextrins, namely CDs functionalized with halotriazine, epoxy, amino, vinylsulfonyl, acryloyl, or methacryloyl groups. Specially functionalized cyclodextrins are expensive. The applicability of products obtained from this process is limited. For example, they are not suitable for RTV-2 type rubbers. The presence of certain functional groups, such as nitrogen-containing amines or triazine residues, may also interfere with certain curing methods, for example, with platinum catalysts used for curing some rubbers. US7,235,186B2 does not mention the compatibility of cyclodextrin-modified silicones with other silicones. The '186 patent also describes crosslinkable silicone compositions based on organosilicon compounds containing cyclodextrin radicals. The silicones described therein and cyclodextrin-modified silicones or silanes are not considered to be compatible and do not react in a homogeneous phase. Therefore, crosslinking is preferably carried out in the form of an emulsion containing additional emulsifiers. The presence of additional emulsifiers, in addition to increasing costs, can negatively affect desirable properties in many applications. Furthermore, various problems arise in many applications due to the leaching of emulsifiers. Crosslinking is based on a condensation reaction and requires temperatures above 100°C. Materials Science and Engineering C 28 (2008) 705-715 describes the synthesis of silicone-containing β-cyclodextrin, but the synthesis involves multiple steps. The β-cyclodextrin is chemically grafted onto a poly(methylhydrosiloxane) polymer or poly(methylhydrosiloxane-co-dimethylsiloxane) copolymer by hydrosilylation. The multi-step synthesis includes regioselectively attaching a tosyl group to one of the primary hydroxyls to convert it to an allyl derivative, followed by acetylation of the remaining hydroxyl group. The final step involves grafting the cyclodextrin derivative onto the silicone polymer by hydrosilylation. This process is too complex and costly, lacking the simplicity required for industrial production. The monoallyl peracetylated β-cyclodextrin derivatives used are incompatible with silicone. To chemically bond this cyclodextrin derivative with the silicone polymer, a large amount of toluene, a flammable and toxic solvent, was required. This product is not cross-linked silicone rubber. DE4324636 describes the modification of alkenyl-functionalized cyclodextrins by hydrosilylation with hydro-functionalized polysiloxanes and their immobilization on support materials for application to chromatographic separation. Here again, since the cyclodextrins used are incompatible with silicone, a large amount of solvent such as toluene is required for the reaction between the CD and the hydro-functionalized silicone. The CD-modified silicones mentioned in this patent are not elastomers. The use of materials for controlled release of active substances is not taught. CN10