Long-acting aromatic micro-capsule with bacteriostasis and emotion healing functions as well as preparation method and application of long-acting aromatic micro-capsule

Abstract

The invention discloses a long-acting aromatic microcapsule with antibacterial and mood healing functions in the field of functional microcapsules, which comprises a core material, a double wall material and an auxiliary agent, and specifically comprises the following components in percentage by weight: 3-30wt% of the core material which is a compound herbal fragrance and comprises 40-50% of cedar wood alcohol, 25-35% of cineole, 15-20% of limonene and less than 10% of trace components, the trace component is at least selected from linalool, caryophyllene and bornyl acetate. Through the innovative design of'double wall materials-composite core materials', the bottleneck that a traditional aromatic microcapsule is poor in high temperature resistance, short in slow release and single in function is broken through, and the three-in-one function of'extreme working condition tolerance, long-acting intelligent aroma release and bacteriostatic mood healing 'is achieved. The data of the embodiment shows that the microcapsule not only can adapt to the high-temperature and high-pressure processing technology of building materials such as artificial boards, but also can release beneficial fragrance for a long time, provides a core functional component for construction of an indoor healthy environment, and has remarkable industrialization value.

Description

Technical Field

[0001] This invention relates to the field of functional microcapsules, specifically to long-lasting aromatic microcapsules with antibacterial and mood-healing properties, their preparation methods, and applications. Background Technology

[0002] With the advancement of the Healthy China strategy, the demand for "functionalization" and "health enhancement" of indoor materials is becoming increasingly urgent. Aromatic microcapsules, due to their ability to impart slow-release fragrance to materials, have become a research hotspot. However, existing aromatic microcapsules suffer from three major drawbacks:

[0003] Poor resistance to high temperature and high pressure: The production of artificial boards requires a hot pressing process of 250-300℃ / 20-30MPa. Under this condition, the integrity rate of traditional microcapsules (such as melamine resin / PVA coating) is <50%, and the fragrance decomposition rate is over 95%.

[0004] Short sustained-release period and poor controlled-release performance: The effective release period of aroma of existing products is generally less than 6 months, and there is a lack of environmental response mechanism, so the release rate cannot be adjusted according to conditions such as temperature.

[0005] Limited functionality: Most microcapsules only have aroma function and lack value-added properties such as antibacterial and mood-healing properties. Moreover, their failure rate is >70% in acidic and alkaline adhesive environments with pH 2-11, making them difficult to adapt to building material processing scenarios.

[0006] Furthermore, existing herbal fragrance blends largely rely on experience and lack integration with traditional Chinese medicine theory and modern pharmacological verification, thus failing to simultaneously achieve the dual effects of "antibacterial and mood regulation." For example, although the long-lasting fragrance microcapsules disclosed in patent CN202411188702.7 employ double-layer encapsulation, the inner wall material is ordinary resin, which can only withstand high temperatures of 200°C and lacks antibacterial and mood-regulating functions. The microcapsule sustained-release period of the literature "Melamine Resin / Polyvinyl Alcohol Double-Encapsulated Microcapsule Fragrance" (Tang Guorui, 2015) is only 12 months, and it does not involve functional expansion.

[0007] Therefore, those skilled in the art have provided long-acting aromatic microcapsules with antibacterial and mood-healing properties to address the problems mentioned in the background art. Summary of the Invention

[0008] The purpose of this invention is to provide long-lasting aromatic microcapsules with antibacterial and mood-healing properties to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] Long-lasting aromatic microcapsules with antibacterial and mood-healing properties are composed of a core material, a double wall material, and excipients, specifically including:

[0011] Core material (3-30wt%): It is a compound herbal fragrance containing, by weight percentage, 40-50% cedrol, 25-35% eucalyptol, 15-20% limonene, and <10% trace components, wherein the trace components are selected from at least linalool, caryophyllene, and bornyl acetate;

[0012] Double-layer wall material (69.5-96.5 wt%): Composed of the following:

[0013] Inner wall material (80-85 wt%, based on the total weight of the two wall materials): a rigid polyurea network formed by compounding amino POSS, HDI trimer, and terminal amino polyether in a mass ratio of 1.2:4.0:2.5;

[0014] Outer wall material (12-18 wt%, based on the total weight of the two wall materials): a temperature-sensitive unit composed of PVCL-b-PEG block copolymer (Mn=15k, PEG content 45%), with a minimum critical melting temperature (LCST) of 50±2℃;

[0015] Additive (0.5wt%): Dibutyltin dilaurate, as a polymerization catalyst.

[0016] As a further aspect of the present invention: the core material is extracted by supercritical CO2 extraction or molecular distillation technology, and the purity of the components is confirmed by GC-MS / O analysis: cypressin > 99%, eucalyptol > 98%, limonene > 97%.

[0017] As a further aspect of the present invention: the inner wall material has an integrity rate of >95% under hot pressing conditions of 250-300℃ / 20-30MPa, and a slow-release rate decay of <8% within the pH range of 2-11.

[0018] As a further aspect of the present invention: when the temperature is >50°C, the PVCL segments hydrophobically shrink to form release channels, increasing the aroma release rate by 3-5 times; when the temperature is <50°C, the PEG segments maintain a hydrophilic microporous structure, and the aroma release rate is <0.5mg / (g·d).

[0019] As a further aspect of the present invention: the microcapsules have an antibacterial rate of >80% against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa (at a concentration of 16 mg / mL), and a protective rate against oxidative damage to PC12 nerve cells of >70% (at a concentration of 0.075 mg / mL).

[0020] A method for preparing long-acting aromatic microcapsules with antibacterial and mood-healing properties includes the following steps:

[0021] S1: Oil phase preparation: Dissolve aminoPOSS, HDI trimer, and PVCL-b-PEG in ethyl acetate to form an oil phase, wherein the mass ratio of aminoPOSS, HDI trimer, and PVCL-b-PEG is 1.2:4.0:0.6;

[0022] S2: Emulsification: Add the core material to the oil phase and homogenize at 12000 rpm for 5 min to form a W / O type emulsion (core material dispersed phase particle size 1-3 μm);

[0023] S3: In-situ polymerization: Add amino-terminated polyether and dibutyltin dilaurate dropwise to the emulsion, stir at 60°C for 2 hours to form a double wall material coating structure;

[0024] S4: Post-processing: Collect microcapsules by centrifugation (5000 rpm, 10 min), wash three times with ethyl acetate, and vacuum dry at 40℃ for 8 h to obtain microcapsules with an average particle size of 7.48±2.1 μm.

[0025] As a further aspect of the present invention: in step S1, the amount of ethyl acetate used is 8-10 times the total mass of the oil phase solid components to ensure complete dissolution of the wall material raw materials; in step S3, the drop acceleration rate of the terminal amino polyether is 0.5 mL / min to avoid local polymerization being too fast and causing defects in the wall material.

[0026] The application of long-lasting aromatic microcapsules with antibacterial and mood-healing properties involves dispersing the microcapsules at an addition rate of 5-10 wt% in an aqueous acrylic resin and coating them onto the surface of melamine-impregnated paper (130 g / m²). 2 After being hot-pressed at 180-220℃ for 3-5 minutes, the microcapsule survival rate is >80%, and the aroma sustained release period reaches 30-36 months (accelerated test equivalent to room temperature).

[0027] As a further aspect of the present invention: when the microcapsules are applied to artificial boards, the boards can have an emotional healing function: when exposed to the aroma released by the boards, mice's weight-bearing swimming time increased by 12.7% and their deep sleep latency was shortened by 25%.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] This invention, through an innovative design of "dual wall material - composite core material," overcomes the limitations of traditional aromatic microcapsules, such as poor resistance to high temperature differences, short-term sustained release, and limited functionality. It achieves a three-in-one function: "extreme working condition tolerance - long-lasting intelligent fragrance release - antibacterial and mood-regulating effects." Data from the embodiments show that this microcapsule is not only compatible with the high-temperature and high-pressure processing of building materials such as engineered wood panels, but also releases beneficial aromas over a long period, providing a core functional component for building a healthy indoor environment and possessing significant industrialization value. Attached Figure Description

[0030] Figure 1 The image shows an SEM image (accelerating voltage 2.0 kV) of the microcapsules in Example 1 of the present invention, which shows that the microcapsules are regular spherical with porous and wrinkled surfaces and an average particle size of 7.48 ± 2.1 μm. Figure 2 The TGA curve of the microcapsules in Example 1 of this invention (N2 atmosphere, heating rate 10℃ / min) shows a weight loss of <5% in the 200-300℃ range, proving its high-temperature resistance. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Example 1: Please refer to Figure 1 Microcapsule preparation and basic performance testing

[0036] Raw material ratio (based on a total mass of 10g)

[0037] Core material: 0.3g (cypressol 0.15g, cineole 0.08g, limonene 0.05g, linalool 0.02g);

[0038] Inner wall material: 7.7g (amino POSS 0.85g, HDI trimer 4.0g, amino-terminated polyether 2.85g);

[0039] Outer wall material: 1.2g (PVCL-b-PEG block copolymer);

[0040] Excipient: 0.05g (dibutyltin dilaurate);

[0041] Solvent: 40 mL of ethyl acetate.

[0042] Preparation steps

[0043] S1: Oil phase preparation: Dissolve aminoPOSS, HDI trimer, and PVCL-b-PEG in 40 mL of ethyl acetate and stir magnetically for 30 min until completely dissolved.

[0044] S2: Emulsification: Add core material and homogenize at 12000 rpm for 5 minutes to form a milky white W / O emulsion;

[0045] S3: In-situ polymerization: Add amino-terminated polyether and dibutyltin dilaurate dropwise, stir at 60°C for 2 hours, and the system gradually becomes viscous.

[0046] S4: Post-treatment: Centrifuge at 5000 rpm for 10 min, collect the precipitate, wash three times with ethyl acetate, and vacuum dry at 40℃ for 8 h to obtain white powdery microcapsules.

[0047] Performance test results

[0048] Particle size distribution: Measured by laser particle size analyzer, D50 = 7.48 μm, Span = 0.32 (uniform distribution);

[0049] Thermal stability (TGA): 4.8% weight loss at 200-300℃, main chain decomposition begins above 300℃, initial decomposition temperature is 283℃;

[0050] Sustained-release performance: Accelerated release test at 50℃ (simulating summer high temperature), aroma residue rate was 62% on day 30, equivalent to 30 months at room temperature;

[0051] Antibacterial properties: Tested using the 96-well plate method, at a concentration of 16 mg / mL, the inhibition rate against Staphylococcus aureus was 87%, against Escherichia coli was 89%, and against Pseudomonas aeruginosa was 81.7%.

[0052] Antioxidant performance: DPPH method (63.7% scavenging rate at 8 mg / mL concentration) and ABTS method (52.8% scavenging rate at 8 mg / mL concentration) demonstrate free radical scavenging ability.

[0053] TGA data fully validates the ability of POSS-modified polyurea-PVCL-PEG hybrid microcapsules to withstand extreme processing conditions. A zero-weight-loss plateau at 200–300°C and a high initial decomposition temperature of 283°C give them a significant advantage in the high-temperature, high-pressure environment of engineered wood products, meeting the stringent requirements for thermal stability of embedded fragrance releasers.

[0054] Example 2: Verification of Emotional Healing Function

[0055] Animal experimental design

[0056] Experimental subjects: Male ICR mice (6 weeks old, 22±2g) were divided into a blank group (ethanol solvent) and a microcapsule group (10mg / mL fragrance solution), with 10 mice in each group;

[0057] Administration method: Nasal instillation, 0.1 mL / animal, once daily for 21 consecutive days;

[0058] Test indicators: weighted swimming test (anti-fatigue), open field test (anti-anxiety), sleep latency measurement (sleep aid).

[0059] Experimental results

[0060] Anti-fatigue: The time to exhaustion during swimming with a load (5% of body weight) in the microcapsule group was 18.5±2.3 min, which was 12.7% higher than that in the blank group (16.4±1.8 min);

[0061] Anti-anxiety effect: In the open field test, the time spent in the central region of mice in the microcapsule group was 45.2±5.1s, which was 40% lower than that in the control group (75.3±6.2s), and the distance traveled was reduced by 38%.

[0062] Sleep aid: In the sodium pentobarbital sleep-inducing experiment, the sleep latency in the microcapsule group was 12.3±1.5 min, which was 25% shorter than that in the control group (16.4±2.1 min), and the total sleep time was extended by 18%.

[0063] Example 3: Neuroprotective Function Test

[0064] Cellular Experiment Design

[0065] Cell line: PC12 neural cells (rat adrenal medullary chromaffin cells);

[0066] Damage model: 400 μM H2O2 induced cellular oxidative damage;

[0067] Groups: Normal group (no damage), damaged group (H2O2 only), and drug-treated group (H2O2 + 0.075 mg / mL microcapsule fragrance).

[0068] Experimental results

[0069] Cell viability was determined by MTT assay: the viability of the drug-treated group was 70.9±3.2%, which was 34.5% higher than that of the damaged group (52.7±2.8%), demonstrating that it has a protective effect against oxidative damage to nerve cells.

[0070] Example 4: Verification of the Application of Wood-based Panels

[0071] Application process

[0072] Substrate: Melamine-impregnated paper (130g / m²) 2 (Moisture content 6.2%)

[0073] Coating: The microcapsules were dispersed in an aqueous acrylic resin (50% solids) at an addition rate of 8 wt%, with a coating amount of 15 g / m³. 2 Pre-dry at 80℃ for 10 minutes;

[0074] Hot pressing: Hot pressing at 220℃ / 25MPa for 4min to prepare fragrance-releasing impregnated paper.

[0075] Fragrance carrier: POSS-polyurea / PVCL-PEG hybrid microcapsules (self-made, oil loading rate 20%, d = 15.3 ± 2.1 μm);

[0076] Immobilizing medium: water-based acrylate resin (Wanhua Chemical, 50% solid content), nanocellulose (Celluforce, d=20nm);

[0077] Detection reagents: acetylacetone chromogenic solution (GB / T 17657), cortisol ELISA kit (Abcam, LOD 0.1n).

[0078] Main experimental instruments and equipment

[0079] Instrument Name model Manufacturer Low-temperature plasma treatment machine Harrick PDC-32G / UV laser drilling machine LPKF BLP-200 Automatic hot press 50T Huzhou Hongqiao Gas Chromatography-Mass Spectrometry Agilent 7890B-5977B Agilent Glass dryer

[0080] Performance testing

[0081] Microcapsule survival rate: Fragrance retention rate was determined by GC-MS after hot pressing, and the survival rate was 82%.

[0082] Sustained-release period: After 36 months of storage at room temperature, the aroma concentration released by the board remains at 0.1-0.3 mg / m³. 3 (Human comfort range);

[0083] Antibacterial properties: The antibacterial test on the surface of the board showed an antibacterial rate of 78% against Staphylococcus aureus, which meets the requirements of GB / T31402-2015 "Test Method for Antibacterial Properties of Plastic Surfaces".

[0084] Analysis of the test data from the embodiments shows that this application has the following advantages:

[0085] 1) Significantly improved tolerance to extreme working conditions: The inner amino POSS-polyurea network enables the microcapsules to achieve an integrity rate of >95% after hot pressing at 250-300℃, which is more than twice that of traditional microcapsules (survival rate of <50% after hot pressing at 180℃).

[0086] 2) Long-lasting intelligent fragrance release: The outer temperature-sensitive wall material regulates the fragrance release, with a release rate of <0.5mg / (g·d) at room temperature. The equivalent room temperature sustained release period in accelerated tests reaches 30-36 months, which is 5-6 times better than traditional technology (<6 months).

[0087] 3) Dual health function integration:

[0088] Antibacterial activity: At a concentration of 16 mg / mL, the antibacterial rates against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were 87%, 89%, and 81.7%, respectively, and the antibacterial activity decreased by <10% in an environment with pH 2-11.

[0089] Emotional healing: After nasal instillation of microcapsule aroma into mice, the swimming time under load increased by 12.7% (anti-fatigue), the distance traveled in the open field decreased by 40% (anti-anxiety), and the deep sleep latency was shortened by 25%; at a concentration of 0.075 mg / mL, the protection rate of PC12 nerve cells damaged by H2O2 reached 70.9%, indicating neuroprotective potential.

[0090] 4) Strong process compatibility: Microcapsules can be directly dispersed in water-based resins and adhesives, and are compatible with existing processes such as hot pressing of artificial boards and coating. The function can be achieved with an addition of 5-10wt%, without the need to modify the production line.

[0091] This application, through an innovative design of "dual wall material - composite core material," overcomes the limitations of traditional aromatic microcapsules, such as poor resistance to high temperature differences, short-term sustained release, and single function. It achieves a three-in-one function: "extreme working condition tolerance - long-lasting intelligent fragrance release - antibacterial and mood-regulating properties." Data from the embodiments show that this microcapsule not only adapts to the high-temperature and high-pressure processing of building materials such as engineered wood panels, but also releases beneficial aromas over a long period, providing a core functional component for building a healthy indoor environment and possessing significant industrialization value.

[0092] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. Long-lasting aromatic microcapsules with antibacterial and mood-healing properties, characterized by: It consists of a core material, a double wall material, and auxiliary agents, specifically including: Core material (3-30wt%): It is a compound herbal fragrance containing, by weight percentage, 40-50% cedrol, 25-35% eucalyptol, 15-20% limonene, and <10% trace components, wherein the trace components are selected from at least linalool, caryophyllene, and bornyl acetate; Double-layer wall material (69.5-96.5 wt%): Composed of the following: Inner wall material (80-85 wt%, based on the total weight of the two wall materials): a rigid polyurea network formed by compounding amino POSS, HDI trimer, and terminal amino polyether in a mass ratio of 1.2:4.0:2.5; Outer wall material (12-18 wt%, based on the total weight of the two wall materials): a temperature-sensitive unit composed of PVCL-b-PEG block copolymer (Mn=15k, PEG content 45%), with a minimum critical melting temperature (LCST) of 50±2℃; Additive (0.5wt%): Dibutyltin dilaurate, as a polymerization catalyst.

2. The long-lasting aromatic microcapsules with antibacterial and mood-healing properties according to claim 1, characterized in that: The core material is extracted using supercritical CO2 extraction or molecular distillation techniques, and the purity of its components is confirmed by GC-MS / O analysis: cypressin > 99%, eucalyptol > 98%, and limonene > 97%.

3. The long-lasting aromatic microcapsules with antibacterial and mood-healing properties according to claim 1, characterized in that: The inner wall material exhibits an integrity rate of >95% under hot-pressing conditions at 250-300℃ / 20-30MPa, and a slow-release rate attenuation of <8% within a pH range of 2-11.

4. The long-lasting aromatic microcapsules with antibacterial and mood-healing properties according to claim 1, characterized in that: When the temperature is >50℃, the outer wall material undergoes hydrophobic shrinkage of PVCL segments to form release channels, increasing the aroma release rate by 3-5 times. At temperatures below 50°C, the PEG segments maintain a hydrophilic microporous structure, and the aroma release rate is <0.5 mg / (g·d).

5. The long-lasting aromatic microcapsules with antibacterial and mood-healing properties according to claim 1, characterized in that: The microcapsules exhibited an inhibition rate of >80% against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa (at a concentration of 16 mg / mL), and a protection rate of >70% against oxidative damage to PC12 neurons (at a concentration of 0.075 mg / mL).

6. A method for preparing long-acting aromatic microcapsules with antibacterial and mood-healing properties, applied in the long-acting aromatic microcapsules with antibacterial and mood-healing properties as described in any one of claims 1-5, characterized in that: Includes the following steps: S1: Oil phase preparation: Dissolve aminoPOSS, HDI trimer, and PVCL-b-PEG in ethyl acetate to form an oil phase, wherein the mass ratio of aminoPOSS, HDI trimer, and PVCL-b-PEG is 1.2:4.0:0.6; S2: Emulsification: Add the core material to the oil phase and homogenize at 12000 rpm for 5 min to form a W / O type emulsion (core material dispersed phase particle size 1-3 μm); S3: In-situ polymerization: Add amino-terminated polyether and dibutyltin dilaurate dropwise to the emulsion, stir at 60°C for 2 hours to form a double wall material coating structure; S4: Post-processing: Collect microcapsules by centrifugation (5000 rpm, 10 min), wash three times with ethyl acetate, and vacuum dry at 40℃ for 8 h to obtain microcapsules with an average particle size of 7.48±2.1 μm.

7. The method for preparing long-acting aromatic microcapsules with antibacterial and mood-healing properties according to claim 6, characterized in that: In step S1, the amount of ethyl acetate used is 8-10 times the total mass of the oil phase solid components to ensure complete dissolution of the wall material raw materials; in step S3, the terminal amino polyether drop rate is 0.5 mL / min to avoid excessively rapid local polymerization leading to wall material defects.

8. The application of the long-acting aromatic microcapsules with antibacterial and mood-healing properties as described in any one of claims 1-5, characterized in that: The microcapsules were dispersed in an aqueous acrylate resin at an addition rate of 5-10 wt%, and then coated onto the surface of melamine-impregnated paper (130 g / m²). 2 After being hot-pressed at 180-220℃ for 3-5 minutes, the microcapsule survival rate is >80%, and the aroma sustained release period reaches 30-36 months (accelerated test equivalent to room temperature).

9. The application of the long-acting aromatic microcapsules with antibacterial and mood-healing properties as described in claim 8, characterized in that: When the microcapsules are applied to engineered wood panels, they can give the panels an emotional healing function: exposure to the aroma released by the panels increases the weight-bearing swimming time of mice by 12.7% and shortens the deep sleep latency by 25%.

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