A hyaluronic acid modified with silicone, a modified liquid silicone elastomer, and a preparation method and application thereof

Abstract

The present application provides a kind of organic silicon modified hyaluronic acid, modified liquid silicone elastomer and its preparation method and application;The organic silicon modified hyaluronic acid includes the following preparation raw materials: hyaluronic acid and vinyl single seal head;The modified liquid silicone elastomer preparation raw materials include the following components: (A) hyaluronic acid with olefinic unsaturated group;(B) organic polysilane with at least two olefinic unsaturated groups;(C) organic polysiloxane containing at least two SiH groups;(D) carrier fluid;(E) silicon hydrogen addition catalyst;The component (A) is the above-mentioned organic silicon modified hyaluronic acid.The present application introduces the organic silicon modified hyaluronic acid into the organic silicon elastomer segment, and obtains the organic silicon elastomer with excellent spreading, smooth feeling, no sticky wet feeling and transparency.In addition, the present application obtains the modified organic silicon elastomer gel in liquid form, which can be directly applied to various daily chemical products.

Description

Technical Field

[0001] This invention belongs to the field of organosilicon technology, specifically relating to organosilicon-modified hyaluronic acid, modified liquid organosilicon elastomers, their preparation methods and applications. Background Technology

[0002] Hyaluronic acid is an acidic mucopolysaccharide with excellent moisturizing effects, and is known as an ideal natural moisturizing factor. When used in cosmetics, it provides excellent skin protection, keeping skin moisturized and smooth, and has anti-wrinkle, anti-aging, beauty-enhancing, and skin-restoring effects. It is also widely used in personal care products, but it suffers from poor film-forming properties, a sticky feel, and an unpleasant skin texture.

[0003] In addition, using hyaluronic acid in combination with silicone elastomers can improve the moisturizing properties of silicone elastomers. However, currently, hyaluronic acid and silicone elastomers are usually physically blended. Hyaluronic acid has poor film-forming and spreading properties, so it cannot achieve a good moisturizing effect.

[0004] CN115232316A discloses an organosilicon elastomer comprising the polymerization product of polymer a and polymer b; wherein polymer a is a sodium hyaluronate-modified polysiloxane with a degree of polymerization of 100-150; and polymer b is a vinyl polysiloxane with a degree of polymerization of 50-80; the molar ratio of polymer b to polymer a is 1:2-1:0.5. By grafting the moisturizing raw material sodium hyaluronate onto the polysiloxane, the resulting organosilicon elastomer possesses moisturizing and hydrating effects and exhibits good skin compatibility when applied to cosmetic products. However, this organosilicon elastomer is a solid elastomer, requiring pulverization after the reaction before use, and it does not achieve optimal sensory properties.

[0005] Therefore, providing a modified liquid silicone elastomer with good moisturizing effect is a technical problem that needs to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides an organosilicon-modified hyaluronic acid, a modified liquid organosilicon elastomer, and their preparation methods and applications.

[0007] In a first aspect, the present invention provides an organosilicon-modified hyaluronic acid, which comprises the following raw materials: hyaluronic acid and vinyl monocapsule.

[0008] Preferably, the mass ratio between the hyaluronic acid and dimethylvinylethoxysilane is 100:(2~25).

[0009] Preferably, the vinyl end cap is dimethylvinylethoxysilane and / or dimethylvinylmethoxysilane.

[0010] Preferably, the raw materials for preparation also include an organotitanium catalyst.

[0011] In a second aspect, the present invention provides a method for preparing organosilicon-modified hyaluronic acid as described in the first aspect, wherein the method comprises reacting hyaluronic acid and vinyl monocapsule under certain conditions to obtain organosilicon-modified hyaluronic acid.

[0012] Preferably, the reaction conditions are: a reaction temperature of 150~190℃ and a reaction pressure of 0.2~0.3 MPa.

[0013] This invention obtains organosilicon-modified hyaluronic acid with double bonds by reacting the carboxyl group of hyaluronic acid with an alkoxy group of vinyl monocapped head.

[0014] Thirdly, the present invention provides a modified liquid organosilicon elastomer, wherein the raw materials for preparing the liquid organosilicon elastomer include the following components:

[0015] (A) Hyaluronic acid with olefinic unsaturated groups;

[0016] (B) Organopolysilanes having at least two olefinic unsaturated groups;

[0017] (C) Organohydrogen polysiloxanes containing at least two SiH groups;

[0018] (D) Carrier fluid;

[0019] (E) Hydrosilylation catalyst;

[0020] The component (A) is the above-mentioned organosilicon-modified hyaluronic acid or the organosilicon-modified hyaluronic acid obtained according to the above preparation method.

[0021] Preferably, the molar ratio between olefinic unsaturated groups and silane groups in the raw materials is 1:0.01~0.2.

[0022] Preferably, the molar ratio between the olefinic unsaturated groups and the silane groups in the raw materials is 1:0.01~0.1.

[0023] Preferably, the molecular weight of component (A) is ≤5000 Da.

[0024] Preferably, component (A) accounts for 0.1 to 5 wt% of the total weight of the liquid silicone elastomer.

[0025] Preferably, the molecular weight of component (B) is 100,000 to 1,300,000.

[0026] Preferably, the molecular weight of component (B) is 900,000 to 1,300,000.

[0027] Preferably, the content of olefinic unsaturated groups in component (B) is 1-6 wt%.

[0028] Preferably, the hydrogen content of component (C) is 0.01~0.5wt%.

[0029] Preferably, the carrier fluid accounts for 75% to 95% of the total weight of the liquid silicone elastomer.

[0030] Fourthly, the present invention provides a method for preparing the above-mentioned modified liquid organosilicon elastomer, the method comprising the following steps:

[0031] The modified liquid organosilicon elastomer is obtained by mixing (A) hyaluronic acid with olefinic unsaturated groups, (B) organopolysilane with at least two olefinic unsaturated groups, (C) organohydrogen polysiloxane containing at least two SiH groups, and (E) hydrosilylation catalyst in (D) carrier fluid.

[0032] Preferably, the reaction temperature is 70~120℃.

[0033] Preferably, the reaction time is 2 to 10 hours.

[0034] Preferably, the catalyst is one or more of Pt or Pd catalysts or their complexes, Karstedt catalysts or Speier's catalysts.

[0035] Fifthly, the present invention provides the application of the above-described modified liquid silicone elastomer or the modified liquid silicone elastomer gel obtained by the above-described method for preparing the modified liquid silicone elastomer in daily chemical products.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The organosilicon-modified hyaluronic acid provided by the present invention is obtained by modifying hyaluronic acid with organosilicon monomers. The organosilicon-modified hyaluronic acid has a strong moisturizing effect on the skin, and can eliminate the sticky feeling and increase the smoothness on the skin surface. It has strong stability at high temperature and has reactivity.

[0038] 2. This invention introduces silicone-modified hyaluronic acid into the silicone elastomer chain segments, resulting in a silicone elastomer with excellent spreadability, smoothness, non-stickiness, and transparency. Furthermore, the modified silicone elastomer gel obtained by this invention is in liquid form and can be directly applied to various daily chemical products. Detailed Implementation

[0039] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be considered as specific limitations thereof. Unless otherwise specified, parts and percentages in the following embodiments refer to parts by weight and percentage by weight, respectively, and the instruments and methods used are conventional instruments and methods in the art.

[0040] The sodium hyaluronate used in Preparation Examples 1 and 2 of this invention is hydrolyzed sodium hyaluronate (molecular weight ≤5000Da), which can be obtained through public channels, such as Bloomage Biotechnology.

[0041] The sodium hyaluronate used in Preparation Example 3 of this invention is low molecular weight sodium hyaluronate (molecular weight of 10kDa-1MPa), which can be obtained through public channels, such as Bloomage Biotechnology.

[0042] The preparation method of unmodified hyaluronic acid includes the following steps: dissolve the above-mentioned sodium hyaluronate in deionized water, slowly add 1 mol / L hydrochloric acid aqueous solution with stirring until the pH is about 2.0, continue stirring for 2 h, put the solution into a dialysis bag, dialyze in deionized water for 3 days to remove sodium ions and hydrochloric acid, and freeze-dry to obtain unmodified hyaluronic acid.

[0043] Vinyl polysiloxane, double-ended hydrogen-containing silicone oil, and side-ended hydrogen-containing silicone oil are all commonly used basic raw materials in this field and can be obtained through public channels.

[0044] The description of the source or composition of the raw materials in this specification is to meet the requirement of full disclosure and does not imply that the present invention cannot be achieved by using other similar raw materials or raw materials provided by other suppliers.

[0045] Preparation Example 1

[0046] A method for preparing organosilicon-modified hyaluronic acid includes the following steps:

[0047] (1) Dissolve the above sodium hyaluronate in deionized water, slowly add 1 mol / L hydrochloric acid aqueous solution while stirring until the pH is about 2.0, continue stirring for 2 h, then put the solution into a dialysis bag and dialyze in deionized water for 3 days to remove sodium ions and hydrochloric acid. After freeze drying, unmodified hyaluronic acid is obtained.

[0048] (2) 50 parts of the above unmodified hyaluronic acid (molecular weight of 1156 Da) and 8.4 parts of dimethylvinylethoxysilane were added to the reaction vessel, and 0.1 parts of tetrabutyl titanate were added. The pressure was controlled at 0.2 MPa and the temperature was controlled at 180 °C. The reaction was carried out for 5 hours to obtain organosilicon modified hyaluronic acid (A1).

[0049] Preparation Example 2

[0050] A method for preparing organosilicon-modified hyaluronic acid includes the following steps:

[0051] (1) Dissolve the above sodium hyaluronate in deionized water, slowly add 1 mol / L hydrochloric acid aqueous solution while stirring until the pH is about 2.0, continue stirring for 2 h, then put the solution into a dialysis bag and dialyze in deionized water for 3 days to remove sodium ions and hydrochloric acid. After freeze drying, unmodified hyaluronic acid is obtained.

[0052] (2) 50 parts of the above unmodified hyaluronic acid (molecular weight of 3052 Da) and 3.8 parts of dimethyl vinyl methoxysilane were added to the reaction vessel, and 0.1 parts of tetrabutyl titanate were added. The pressure was controlled at 0.4 MPa and the temperature was controlled at 160 °C. The reaction was carried out for 3 h to obtain organosilicon modified hyaluronic acid (A2).

[0053] Preparation Example 3

[0054] The difference between this preparation example and preparation example 1 is that the unmodified sodium hyaluronate used in this preparation example is different. The low molecular weight sodium hyaluronate (molecular weight of 10kDa) is used in this preparation example, and organosilicon-modified hyaluronic acid (A3) is prepared by the same preparation method as preparation example 1.

[0055] Preparation Example 4

[0056] A method for preparing a vinyl polysiloxane is as follows:

[0057] 188g of octamethylcyclotetrasiloxane, 12.28g of tetramethyltetravinylcyclotetrasiloxane, and 0.104g of octamethyltrisiloxane were added to a reaction vessel, heated to 60°C, and dehydrated under reduced pressure for 2 hours. Then, dry nitrogen gas was introduced and the temperature was raised to 150°C. Potassium hydroxide silanolate was added, and the reaction was carried out for 2 hours. After that, the temperature was raised to 200°C, and small molecule low-boiling substances were removed under vacuum for 1 hour. The mixture was then cooled to room temperature to obtain vinyl polysiloxane B1 (number average molecular weight of 920,000 and vinyl content of 1.92 wt%).

[0058] Preparation Example 5

[0059] A method for preparing a vinyl polysiloxane is as follows:

[0060] 197.12 g of octamethylcyclotetrasiloxane, 6.4 g of tetramethyltetravinylcyclotetrasiloxane, and 0.0621 g of octamethyltrisiloxane were added to a reaction vessel, heated to 60 °C, and dehydrated under reduced pressure for 2 h. Then, dry nitrogen gas was introduced and the temperature was raised to 140 °C. Potassium hydroxide silanolate was added, and the reaction was carried out for 2 h. After that, the temperature was raised to 180 °C, and small molecule low-boiling substances were removed under vacuum for 1 h. The mixture was then cooled to room temperature to obtain vinyl polysiloxane B2 (number average molecular weight of 1.31 million and vinyl content of 1 wt%).

[0061] Preparation Example 6

[0062] A method for preparing a vinyl polysiloxane is as follows:

[0063] 188g of octamethylcyclotetrasiloxane, 12.28g of tetramethyltetravinylcyclotetrasiloxane, and 0.96g of octamethyltrisiloxane were added to a reaction vessel, heated to 60°C, and dehydrated under reduced pressure for 2 hours. Then, dry nitrogen gas was introduced and the temperature was raised to 150°C. Potassium hydroxide silanolate was added, and the reaction was carried out for 2 hours. After that, the temperature was raised to 200°C, and small molecule low-boiling substances were removed under vacuum for 1 hour. The mixture was then cooled to room temperature to obtain vinyl polysiloxane B3 (number average molecular weight of 103,000 and vinyl content of 1.94 wt%).

[0064] Preparation Example 7

[0065] A method for preparing a vinyl polysiloxane is as follows:

[0066] 188g of octamethylcyclotetrasiloxane, 12.28g of tetramethyltetravinylcyclotetrasiloxane, and 9.6g of octamethyltrisiloxane were added to a reaction vessel, heated to 60°C, and dehydrated under reduced pressure for 2 hours. Then, dry nitrogen gas was introduced and the temperature was raised to 150°C. Potassium hydroxide silanolate was added, and the reaction was carried out for 2 hours. After that, the temperature was raised to 200°C, and small molecule low-boiling substances were removed under vacuum for 1 hour. The mixture was then cooled to room temperature to obtain vinyl polysiloxane B4 (number average molecular weight of 12,000 and vinyl content of 1.91 wt%).

[0067] Preparation Example 8

[0068] 193.9 g of octamethylcyclotetrasiloxane, 6.4 g of tetramethyltetravinylcyclotetrasiloxane, and 0.0946 g of octamethyltrisiloxane were added to a reaction vessel, heated to 60 °C, and dehydrated under reduced pressure for 2 h. Then, dry nitrogen gas was introduced and the temperature was raised to 150 °C. Potassium hydroxide silanolate was added, and the reaction was carried out for 2 h. After that, the temperature was raised to 200 °C, and small molecule low-boiling substances were removed under vacuum for 1 h. The mixture was then cooled to room temperature to obtain vinyl polysiloxane B5 (number average molecular weight of 1.01 million and vinyl content of 1 wt%). Example 1

[0069] A modified liquid organosilicon elastomer, the raw materials for which are prepared include, by weight:

[0070] 10.74 parts by weight of double-ended hydrogen-containing silicone oil (hydrogen content of 0.01 wt%, viscosity of 400 mPa·s), 130 parts by weight of vinyl polysiloxane (B1, molecular weight of 920,000, vinyl content of 1.92 wt%), 15 parts by weight of organosilicon-modified hyaluronic acid (A1), 20 ppm of caster catalyst and 850 parts by weight of polydimethylsiloxane (5 cst), with a molar ratio of vinyl to silanol groups of 1:0.01.

[0071] The preparation method of the above-mentioned modified liquid organosilicon elastomer is as follows:

[0072] Two-terminal hydrogen-containing silicone oil, vinyl polysiloxane, organosilicon-modified hyaluronic acid (A1), and polydimethylsiloxane (5cst) were added to a reactor, stirred, and after adding the caster catalyst, the temperature was raised to 100°C. After reacting for 5 hours, a sample was taken for infrared detection. After confirming that the characteristic peak of silane-hydrogen disappeared, the temperature was lowered to obtain the modified liquid organosilicon elastomer. Example 2

[0073] A modified liquid organosilicon elastomer, the raw materials for which are prepared include, by weight:

[0074] 15.6 parts by weight of polydimethylsiloxane (0.18% hydrogen content, 80 mPa·s viscosity), 121.5 parts by weight of vinyl polysiloxane (B2, molecular weight 1.3 million, vinyl content 1 wt%), 10 parts by weight of organosilicon-modified hyaluronic acid (A2), 30 ppm of caster catalyst and 2304.5 parts by weight of polydimethylsiloxane (2 cst), with a molar ratio of vinyl to silanol groups of 1:0.1.

[0075] The preparation method of the above-mentioned modified liquid organosilicon elastomer is as follows:

[0076] The above-mentioned organosilicon-modified hyaluronic acid (A2) and polydimethylmethylhydrosiloxane were added to a reaction vessel, nitrogen gas was introduced, stirring was started, and the caster catalyst was added to the reaction vessel. The temperature was raised to 100°C for reaction. After 5 hours of reaction, hyaluronic acid-modified hydrogen-containing silicone oil was obtained.

[0077] The above-mentioned hyaluronic acid modified hydrogen-containing silicone oil, vinyl polysiloxane, and polydimethylsiloxane (5cst) were added to a reactor, stirred, and heated to 110°C. Platinum catalyst was added to the reactor and the temperature was raised to 110°C for reaction. After the reaction was maintained at this temperature for 7 hours, a sample was taken for infrared detection. After confirming that the characteristic peak of silane-hydrogen disappeared, the temperature was lowered and the modified liquid organosilicon elastomer was discharged. Example 3

[0078] A modified liquid organosilicon elastomer, the raw materials for which are prepared include, by weight:

[0079] 13.6 parts by weight of dual-ended hydrogen-containing silicone oil (0.1 wt% hydrogen content, 50 mPa·s viscosity), 130 parts by weight of vinyl polysiloxane (B5, number average molecular weight 1.01 million, vinyl content 1 wt%), 20 parts by weight of organosilicon-modified hyaluronic acid (A1), 20 ppm of caster catalyst and 654.4 parts by weight of polydimethylsiloxane (5 cst), with a molar ratio of vinyl to silanol groups of 1:0.2.

[0080] The preparation method of the above-mentioned modified liquid organosilicon elastomer is as follows:

[0081] Two-terminal hydrogen-containing silicone oil, vinyl polysiloxane, organosilicon-modified hyaluronic acid (A1), and polydimethylsiloxane (5cst) were added to a reactor, stirred, and after adding the caster catalyst, the temperature was raised to 105°C. After reacting for 6 hours, a sample was taken for infrared detection. After confirming that the characteristic peak of silane-hydrogen disappeared, the temperature was lowered to obtain the modified liquid organosilicon elastomer. Example 4

[0082] A modified liquid organosilicon elastomer, the raw materials for which are prepared include, by weight:

[0083] 10 parts by weight of double-ended hydrogen-containing silicone oil (hydrogen content of 0.01%, viscosity of 400 mPa·s), 130 parts by weight of vinyl polysiloxane (B3, molecular weight of 103,000, vinyl content of 1.94 wt%), 15 parts by weight of organosilicon-modified hyaluronic acid (A1), 20 ppm of caster catalyst and 850 parts by weight of polydimethylsiloxane (5 cst), with a molar ratio of vinyl to silanol groups of 1:0.01.

[0084] The preparation method of the above-mentioned modified liquid organosilicon elastomer is as follows:

[0085] Two-terminal hydrogen-containing silicone oil, vinyl polysiloxane, organosilicon-modified hyaluronic acid (A1), and polydimethylsiloxane (5cst) were added to a reactor, stirred, and after adding the caster catalyst, the temperature was raised to 100°C. After reacting for 5 hours, a sample was taken for infrared detection. After confirming that the characteristic peak of silane-hydrogen disappeared, the temperature was lowered to obtain the modified liquid organosilicon elastomer. Example 5

[0086] The only difference between this embodiment and Embodiment 1 is that the vinyl polysiloxane used in this embodiment is vinyl polysiloxane (B4) (number average molecular weight of 12,000 and vinyl content of 1.91 wt%). Example 6

[0087] The difference between this embodiment and Embodiment 1 is that the silicone-modified hyaluronic acid used in this embodiment is silicone-modified hyaluronic acid (A3). Example 7

[0088] A modified liquid organosilicon elastomer, the raw materials for which are prepared include, by weight:

[0089] 112 parts by weight of dual-ended hydrogen-containing silicone oil (hydrogen content of 0.01 wt%, viscosity of 400 mPa·s), 22.7 parts by weight of vinyl polysiloxane (B1, molecular weight of 920,000, vinyl content of 1.92 wt%), 15 parts by weight of organosilicon-modified hyaluronic acid (A1), 20 ppm of caster catalyst and 850 parts by weight of polydimethylsiloxane (5 cst), with a molar ratio of vinyl to silanol groups of 1:0.7.

[0090] The preparation method of the above-mentioned modified liquid organosilicon elastomer is as follows:

[0091] Two-terminal hydrogen-containing silicone oil, vinyl polysiloxane, organosilicon-modified hyaluronic acid (A1), and polydimethylsiloxane (5cst) were added to a reactor, stirred, and after adding the caster catalyst, the temperature was raised to 100°C. After reacting for 5 hours, a sample was taken for infrared detection. After confirming that the characteristic peak of silane-hydrogen disappeared, the temperature was lowered to obtain the modified liquid organosilicon elastomer. Example 8

[0092] A modified liquid organosilicon elastomer, the raw materials for which are prepared include, by weight:

[0093] 168 parts by weight of double-ended hydrogen-containing silicone oil (hydrogen content of 0.01 wt%, viscosity of 400 mPa·s), 22.7 parts by weight of vinyl polysiloxane (B1, molecular weight of 920,000, vinyl content of 1.92 wt%), 15 parts by weight of organosilicon-modified hyaluronic acid (A1), 20 ppm of caster catalyst and 850 parts by weight of polydimethylsiloxane (5 cst), with a molar ratio of vinyl to silanol groups of 1:1.05.

[0094] The preparation method of the above-mentioned modified liquid organosilicon elastomer is as follows:

[0095] Two-terminal hydrogen-containing silicone oil, vinyl polysiloxane, organosilicon-modified hyaluronic acid (A1), and polydimethylsiloxane (5cst) were added to a reactor, stirred, and after adding the caster catalyst, the temperature was raised to 100°C. After reacting for 5 hours, a sample was taken for infrared detection. After confirming that the characteristic peak of silane-hydrogen disappeared, the temperature was lowered to obtain the modified liquid organosilicon elastomer.

[0096] Comparative Example 1

[0097] The only difference between this comparative example and Example 1 is that the double-bond modified hyaluronic acid used in this comparative example is acrylate modified hyaluronic acid with the same molecular weight.

[0098] Comparative Example 2

[0099] The difference between this comparative example and Example 1 is that the silicone-modified hyaluronic acid in this comparative example is replaced with an equal mass of unmodified hyaluronic acid.

[0100] Performance testing:

[0101] The modified liquid organosilicon elastomer gels obtained in Examples 1 to 8, as well as Comparative Examples 1 and 2, were evaluated for the following sensory properties. The evaluation results are shown in Table 1.

[0102] Stringiness: Based on the length of the product that is stretched when stretched, it is divided into 1-9 levels from low to high.

[0103] Appearance: Based on the transparency of the product, it is divided into 1-5 levels from low to high.

[0104] Table 1

[0105]

[0106] As shown in Table 1, the modified liquid silicone elastomer gel obtained in the embodiments of the present invention has better stringing effect and transparent appearance. A comparison of Examples 1 and Examples 4-8 shows that when the molecular weight of the vinyl polysiloxane and the molar ratio between vinyl groups and silane-hydrogen bonds are not within a specific range, the stringing effect and transparency of the obtained modified liquid silicone elastomer gel will decrease to varying degrees.

[0107] Moisturizing creams were prepared by mixing the silicone elastomer gels with stringy effect obtained in Examples 1-8 and Comparative Examples 1-2 with other components in the same proportions.

[0108] The composition and preparation method of the moisturizing cream are shown in Table 2.

[0109] Table 2

[0110]

[0111] The moisturizing cream's stringiness, long-lasting moisturizing effect, silky feel, and spreadability were evaluated. The evaluation results are shown in Table 3. A stringy serum without added silicone elastomer gel (which has a stringy effect) was used as a control. The evaluation method for the stringy effect was the same as above, while the evaluation method for the long-lasting silky feel is as follows:

[0112] Ten professional evaluators were selected to assess the silkiness of the prepared moisturizing cream. The evaluation results were divided into 1-10 points, with higher scores indicating better silkiness and refreshing feel, and lower scores indicating poorer silkiness and stickiness or pilling.

[0113] The evaluation method for moisturizing properties is as follows:

[0114] The measurement area on the flexor side of the forearm of the subject was selected as 2x2 cm. 2 Apply 8 μL of product to the test area and pat it in with a fingertip to absorb. Measure the stratum corneum moisture content using a Corneometer CM825 (CK, Germany) before and 4 hours after application. Measure the same point 5 times, excluding the maximum and minimum values, and record the average of the three measurements. Moisturizing effect is characterized by the moisture growth rate, calculated as: (Value 4 hours after application - Value before application) / Value before application. Evaluation is based on three levels: Level 1: <30%; Level 2: 30-50%; Level 3: >50%.

[0115] The evaluation method for spreadability is as follows:

[0116] Ten professional assessment subjects were selected to evaluate the spreadability and smoothness of the prepared cream. An appropriate amount of moisturizing cream was applied to the skin and gently spread with the fingers. If it spreads easily without any astringency and melts upon application, the spreadability is good. If it is difficult to spread and there is resistance, the spreadability is poor. The evaluation results were scored from 1 to 10, with higher scores indicating better spreadability and lower scores indicating poor spreadability.

[0117] Table 3

[0118]

[0119] As shown in Table 3, the modified liquid silicone elastomer in the embodiments of the present invention gives the moisturizing cream a good stringy effect, as well as an excellent silky feel and long-lasting moisturizing effect.

[0120] As can be seen from the comparison between Example 1 and Comparative Example 1, Comparative Example 1 uses acrylate-modified hyaluronic acid, and the resulting moisturizing cream has reduced spreadability, silkiness, and moisturizing duration.

[0121] As can be seen from the comparison between Example 1 and Comparative Example 2, the hyaluronic acid in Comparative Example 2 was not modified by double bonds and was not grafted onto the silicone elastomer chain segment, resulting in a decrease in the spreadability, silkiness and moisturizing duration of the resulting moisturizing cream.

[0122] The applicant declares that this invention illustrates an organosilicon-modified hyaluronic acid, a modified liquid organosilicon elastomer, and their preparation method and application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the products of this invention, additions of auxiliary components, and selection of specific methods all fall within the protection and disclosure scope of this invention.

Claims

1. An organosilicon-modified hyaluronic acid, characterized in that, The raw materials used in its preparation include: hyaluronic acid, dimethylvinylethoxysilane, and organotitanium catalyst; The preparation method of the organosilicon-modified hyaluronic acid includes the following steps: reacting hyaluronic acid, dimethylvinylethoxysilane and organotitanium catalyst at a temperature of 150~190℃ and a pressure of 0.2~0.4Mpa to prepare organosilicon-modified hyaluronic acid; The mass ratio between the hyaluronic acid and dimethylvinylethoxysilane is 100:(2~25).

2. A modified liquid organosilicon elastomer, characterized in that, The raw materials for preparing the modified liquid organosilicon elastomer include the following components: (A) Hyaluronic acid with olefinic unsaturated groups; (B) Organopolysiloxanes having at least two olefinic unsaturated groups; (C) Organohydrogen polysiloxanes containing at least two SiH groups; (D) Carrier fluid; (E) Hydrosilylation catalyst; The component (A) is the organosilicon-modified hyaluronic acid as described in claim 1; The components (A), (B), and (C) undergo a hydrosilylation reaction in component (D).

3. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The molar ratio between olefinic unsaturated groups and silane groups in the raw materials is 1:0.01~0.

2.

4. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The molecular weight of component (A) is ≤5000 Da.

5. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The component (A) accounts for 0.1 to 5 wt% of the total weight of the modified liquid silicone elastomer.

6. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The molecular weight of component (B) is 100,000 to 1,300,000.

7. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The molecular weight of component (B) is 900,000 to 1,300,000.

8. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The content of olefinic unsaturated groups in component (B) is 1~6 wt%.

9. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The hydrogen content of component (C) is 0.01~0.5wt%.

10. The modified liquid organosilicon elastomer according to claim 2, characterized in that, The carrier fluid accounts for 75% to 95% of the total weight of the liquid silicone elastomer.

11. A method for preparing a modified liquid organosilicon elastomer according to any one of claims 2-10, characterized in that, The preparation method of the modified liquid organosilicon elastomer includes the following steps: The modified liquid organosilicon elastomer is obtained by mixing (A) hyaluronic acid with olefinic unsaturated groups, (B) organopolysilane with at least two olefinic unsaturated groups, (C) organohydrogen polysiloxane containing at least two SiH groups, and (E) hydrosilylation catalyst in (D) carrier fluid.

12. The preparation method according to claim 11, characterized in that, The reaction temperature is 70~120℃, and the reaction time is 2~10h.

13. The preparation method according to claim 11, characterized in that, The hydrosilylation catalyst is one or more of Pt or Pd catalysts or their complexes, Karstedt catalysts or Speier's catalysts.

14. The application of the modified liquid silicone elastomer as described in any one of claims 2-10 or the modified liquid silicone elastomer prepared according to the preparation method described in claims 11-13 in daily chemical products.

Images