A method for preparing a seaweed extract composite disinfecting and cleaning detergent composition

Abstract

The present application relates to the technical field of detergent composition, and discloses a preparation method of seaweed extract composite disinfectant and detergent composition, comprising the following steps: under temperature control and stirring, mixing alkyl polyglycoside and quaternary ammonium salt cationic bactericide at a specific molar ratio and a free water content lower than 55%, to build a high-viscosity poor-water lamellar liquid shielding phase; immersing and injecting the shielding phase into a seaweed extract base solution, and obtaining the composition by shearing and dispersing at a specific rate, wherein the present application builds a metastable poor-water lamellar liquid structure, physically isolates the cationic bactericide and anionic seaweed extract by using steric hindrance effect in the mixing moment, effectively blocks flocculation caused by charge pair reaction, realizes thermodynamic stable coexistence and functional compatibility of the two in a single aqueous phase system, and ensures that the bactericidal activity can be released when the composition is used in dilution.

Description

Technical Field

[0001] This invention relates to a method for preparing a composite disinfectant detergent composition based on seaweed extract, belonging to the technical field of detergent compositions. Background Technology

[0002] Currently, in the preparation of detergent compositions, the combination of quaternary ammonium salt cationic bactericides with seaweed extract anionic polymers to obtain products with both high-efficiency disinfection and skin moisturizing effects is a technological pursuit in the daily chemical industry. Quaternary ammonium salts adsorb negatively charged bacterial cell membranes to achieve broad-spectrum bactericidal effects, while seaweed extracts such as sodium alginate utilize polysaccharide skeletons to provide rheological regulation and film-forming skin care properties. The industry usually dissolves functional components in surfactant systems and uses micellar solubilization to maintain the apparent stability of the system. However, the coexistence of strongly positively charged quaternary ammonium salts and high-density negatively charged seaweed polysaccharides in the same aqueous phase system faces the challenge of colloidal chemical charge compatibility. Existing technologies add excessive nonionic surfactants as solubilizers or introduce high concentrations of inorganic salts for charge shielding, which frequently leads to flocculation, stratification, and localized gel phase separation during large-scale production and long-term storage.

[0003] Although existing technologies attempt to balance the compatibility of multiple active ingredients by optimizing the order of feeding or stepwise mixing processes, there are still significant limitations in the microscopic phase regulation of strongly charge-antagonistic components. For example, Chinese invention patent application CN116731795A discloses a disinfectant and antibacterial color bleach and its preparation method. Although it adopts a stepwise mixing strategy, first compounding anionic and nonionic surfactants, and then mixing them with oxidizing agents and anti-dyeing powder, it attempts to improve the stability of the system by utilizing the physical encapsulation and slow-release effect of thickening components. However, this simple mixing or macroscopic encapsulation process based on conventional dilute solutions does not essentially build a microscopic barrier that can effectively block long-range electrostatic attraction at the quantum level. Once such a process is applied to the strong cationic quaternary ammonium salt and high charge density seaweed polysaccharide system involved in this application, the conventional micelle structure cannot effectively suppress double-layer compression and charge neutralization at the interface during mixing. This easily leads to irreversible flocculation of polyelectrolyte complexes, causing the active ingredients to be pinned and locked, thus losing their actual disinfection efficacy.

[0004] Therefore, the technical problem to be solved by the present invention is to block the instantaneous flocculation path between oppositely charged components without relying on excessive exogenous chemical additives by pre-constructing the phase state of the materials in the preparation process and precisely controlling the hybrid dynamics. Summary of the Invention

[0005] To address the problems mentioned in the background art, the technical solution of the present invention is as follows: A method for preparing a seaweed extract composite disinfectant detergent composition, the method comprising the following steps:

[0006] Step 101: Construct a water-deficient layered liquid crystal shielding phase; In a reaction vessel equipped with temperature control and stirring functions, alkyl glycosides and quaternary ammonium cationic bactericides are mixed, and the molar ratio of alkyl glycosides to quaternary ammonium cationic bactericides is controlled to be 5:1 to 9:1. The mass percentage of free water in the mixed system is controlled to be less than 55%, and the free water is the water contained in the raw materials. The mixture is stirred at a rate of 40 to 80 revolutions per minute at 35 to 45 degrees Celsius until the viscosity of the system rises to more than 1000 mPa second, forming a layered liquid crystal structure with anisotropic optical texture, and obtaining an optically transparent water-deficient shielding liquid;

[0007] Step 102: Prepare seaweed polysaccharide hydrated base solution; disperse seaweed extract in deionized water, heat to 50°C to 60°C, and stir until the seaweed extract is completely swollen and dissolved to obtain a clear base solution;

[0008] Step 103, shear-induced immersion dispersion and compounding; turn on the shearing device and set the shear rate to 2500 rpm to 3500 rpm to form a high-shear region in the base liquid. The water-deficient shielding liquid is continuously injected into the high-shear region through a conduit in a manner that is submerged below the liquid surface. The injection rate of the water-deficient shielding liquid is controlled to be 2% to 5% of the total mass per minute. During the injection process in step 103, the water-deficient shielding liquid maintains a layered liquid crystal structure to encapsulate the quaternary ammonium salt cationic bactericide and physically isolates the quaternary ammonium salt cationic bactericide from contact with the seaweed extract before it is dispersed and destroyed.

[0009] Preferably, in step 101, the alkyl glycoside is selected from octyldecyl glucoside or dodecyl glucoside and combinations thereof, with a degree of polymerization of 1.1 to 1.3; stirring is carried out for 30 to 60 minutes, and the transmittance of the mixed system is monitored during stirring. When the transmittance exceeds 98% and the mixed system exhibits shear-thinning fluid characteristics, the construction of the water-deficient layered liquid crystal shielding phase is determined to be complete; no additional process water is added during the entire process of step 101.

[0010] Preferably, in step 101, the quaternary ammonium salt cationic bactericide is selected from dodecyl dimethyl benzyl ammonium chloride, decyl dimethyl ammonium chloride, or hexadecyl trimethyl ammonium chloride and combinations thereof; the hydrophilic head group of the alkyl glycoside in the water-poor shielding solution formed in step 101 forms a hydration layer around the cationic center of the quaternary ammonium salt cationic bactericide, and the hydration layer prevents the anionic chain segments in the seaweed extract from directly contacting the quaternary ammonium salt cationic bactericide during the shear dispersion process in step 103.

[0011] Preferably, in step 102, the seaweed extract is selected from sodium alginate or fucoidan and combinations thereof, and the viscosity of the 1% aqueous solution is 100 mPa·s to 500 mPa·s. Step 102 also includes adjusting the pH value of the base solution to 6.0 to 7.5. The pH adjustment is performed after the seaweed extract has fully swollen and before the compounding operation in step 103, so that the degree of ionization of the base solution during compounding is within a preset range.

[0012] Preferably, in step 103, the injection rate of the water-defense fluid follows the dynamic mass flux control formula: Q in =(M total ×γ) / t mix , where Q in Defined as the instantaneous injection mass flow rate of the water-defense fluid, expressed in grams per minute; M total Defined as the total mass of the water-defense fluid, in grams; t mix Defined as the preset total injection time, in minutes; γ is defined as the dimensionless shear dispersion coefficient, with a value range of 0.8 to 1.2; the injection rate control is used to maintain the local concentration of the water-poor shielding liquid entering the high-shear region above its critical micelle concentration, thus maintaining the integrity of the lamellar liquid crystal structure during the dispersion process.

[0013] Preferably, the preparation method further includes step 104, steady-state locking and post-treatment; step 104 includes: after all the water-defense liquid is injected and evenly dispersed, the system temperature is reduced to below 30 degrees Celsius; chelating agent, fragrance and pH adjuster are added in sequence; bubbles are removed under low-speed frame stirring at 40 to 60 revolutions per minute until a finished detergent composition with uniform appearance and no visible suspended matter is obtained; step 104 is performed after step 103 is completely completed.

[0014] Preferably, in step 103, the high shear region is defined as the gap region between the stator and rotor of the shearing device, and the width of the gap region is 0.2 mm to 0.5 mm; the discharge port of the conduit is fixed at a position 10 mm to 20 mm away from the outer edge of the stator, and the direction of the discharge port is consistent with the tangential direction of the flow field of the base liquid, so as to reduce the physical damage of the layered liquid crystal structure to the turbulent disturbance at the moment of injection.

[0015] Preferably, the preparation method is used to prepare a transparent liquid detergent with a viscosity of 500 mPa·s to 1500 mPa·s; the transparent liquid detergent does not stratify after undergoing an accelerated destructive test of centrifugation at 4000 rpm for 30 minutes, and remains optically transparent after undergoing high and low temperature cycling tests from -5 degrees Celsius to 45 degrees Celsius; the quaternary ammonium salt cationic bactericide in the transparent liquid detergent exists in the form of physical encapsulation by alkyl glycoside micelles and is released into the aqueous phase during the dilution process.

[0016] Preferably, in step 101, the reaction vessel is a stainless steel mixing vessel with a jacketed temperature control device, and the stirring is carried out by an anchor-type stirring paddle; step 101 also includes detecting the change in conductivity of the system in the early stage of mixing, and when the conductivity reading tends to stabilize and no longer fluctuates with the extension of stirring time, it is determined that the alkyl glycoside and the quaternary ammonium salt cationic bactericide have completed thermodynamic equilibrium assembly.

[0017] Preferably, the prepared seaweed extract composite disinfectant detergent composition is a homogeneous transparent fluid; the composition comprises seaweed extract, quaternary ammonium salt cationic bactericide, alkyl glycoside and water; wherein, the quaternary ammonium salt cationic bactericide is encapsulated in a micromicelle core formed by alkyl glycoside, and the seaweed extract is distributed in a continuous aqueous phase outside the micromicelle, and the two are thermodynamically isolated at the microscale by a hydration layer formed by alkyl glycoside.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] 1. In the preparation of a composite disinfectant detergent composition based on seaweed extract, nonionic surfactants and cationic bactericides are pre-assembled under specific molar ratios and low water activity conditions to construct a high-viscosity, high-density layered liquid crystal or micelle shielding phase. The hydrophilic head groups of the nonionic surfactants form a dense hydration steric hindrance layer around the cationic center to resist electrostatic capture by external anionic polymer chains. The shielding phase is dispersed in the seaweed extract solution, so that the cationic core is wrapped by the nonionic surfactant, avoiding direct contact with the anionic skeleton and the precipitation of polyelectrolyte complexes. The irreversible chemical flocculation reaction is transformed into a controllable physical micelle dispersion process. Without introducing exogenous charge shielding agents, the anti-charge components coexist thermodynamically stably in a single aqueous phase system, maintaining the product's uniform and transparent appearance and long-term storage stability.

[0020] 2. Utilizing the preferential solubilization effect of nonionic surfactants on cationic bactericides, a microencapsulated physical encapsulation structure is formed, isolating the cationic bactericide within the micelle core. During storage, it does not chemically bind to the anionic groups of seaweed extract, avoiding double inactivation due to pinning effects. This preserves the thickening and film-forming skin-care properties of seaweed polysaccharides and prevents the active sites of the bactericide from being locked by the polymer network. During washing and use, water dilution disrupts the critical micelle concentration equilibrium of the shielding phase, causing the cationic bactericide to dissociate and release from the micelles into the aqueous phase, restoring its ability to capture the negative charge on bacterial surfaces. Through a dynamic response mechanism of isolation during storage and release during use, the problem of functional mutual exclusion between functional polymers and small molecule bactericides within the same system is solved.

[0021] 3. By immersing the high-viscosity shielding phase into the high-shear region, excessively high local concentrations at the interface during mixing are avoided from a kinetic perspective. The high-viscosity shielding phase cannot diffuse rapidly into the anionic substrate due to rheological limitations. It is torn apart and dispersed into micron-sized independent particles by high shear force, ensuring that the cationic components complete microscale dispersion and interface reconstruction before contacting the anionic environment, thus eliminating primary flocculation nuclei induced by excessively high local charge density. By limiting the feeding sequence and rheological state, a highly stable complex fluid system can be prepared using conventional industrial stirring equipment, reducing dependence on expensive homogenizing equipment. Attached Figure Description

[0022] Figure 1 This is a complete flow diagram of the preparation process of the seaweed extract compound disinfectant detergent composition of the present invention;

[0023] Figure 2 This is a response curve of the particle size of the dispersed phase evolving over time during the shear-induced dispersion process of this invention;

[0024] Figure 3 This is a schematic diagram of the microstructure of the physical isolation mechanism and spatial distribution of micromicelles in the composition of the present invention;

[0025] Figure 4 This is a timing diagram showing the operation flow and monitoring logic of the water-deficient layered liquid crystal shielding phase construction process of the present invention. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0027] This invention provides a method for preparing a composite disinfectant detergent composition based on seaweed extract, which addresses the problems of flocculation, precipitation, and deactivation caused by electrostatic attraction between anionic seaweed polysaccharides and cationic bactericides in the same aqueous system in the detergent field. By constructing a water-poor layered liquid crystal structure as a physical isolation medium, and utilizing the steric hindrance effect of nonionic surfactants, the direct contact between the oppositely charged components is blocked at the moment of mixing, achieving thermodynamically stable coexistence and functional compatibility between the two. The preparation method includes four core process stages: construction of a water-poor layered liquid crystal shielding phase, preparation of seaweed polysaccharide hydration base liquid, shear-induced immersion dispersion and composite, and steady-state locking and post-treatment.

[0028] In constructing a water-deficient layered liquid crystal shielding phase, a limited solvation process is employed to restrict the electrostatic migration of cationic bactericides in a water-rich environment. Alkyl glycosides and quaternary ammonium cationic bactericides are mixed in a reaction vessel equipped with temperature control and anchor stirring. The alkyl glycosides, acting as nonionic surfactants, are used in a molar ratio with the quaternary ammonium cationic bactericides limited to 5:1 to 9:1. The free water percentage in the mixture is controlled to be below 55%, consisting of water inherent to the raw materials without the addition of process water. The system temperature is controlled between 35°C and 45°C, and stirring is performed at a low shear rate of 40 rpm to 80 rpm. Stirring continues until the system viscosity rises above 1000 mPa·s at 25°C, exhibiting an anisotropic optical textured layered liquid crystal structure or a high-concentration micelle phase, resulting in an optically transparent water-deficient shielding liquid. The quantitative calculation of the free water percentage follows industrial raw material standard conversion procedures, using an industrial-grade alkyl glycoside aqueous solution with a solid content of 50% and quaternary ammonium salts with an active ingredient content of 50% to 80%. Based on the raw materials, the total amount of all volatile solvents in each raw material component after removing surfactant actives and solid impurities is defined as the free water mass. The upper limit of 55% free water content is the critical thermodynamic boundary for the system to undergo lyotropic liquid crystal phase transition. The endpoint of the shielded phase construction in the reaction vessel is determined by an online stirring power monitoring procedure. The output torque data of the stirring motor is collected in real time at a constant stirring speed. When the output torque value increases exponentially relative to the initial mixing state and reaches a steady-state plateau value, and the system conductivity reading drops to the lowest stable value, it is determined that the free water in the system is completely bound between the surfactant bilayers, and the lamellar liquid crystal structure is completed. This serves as the objective basis for stopping stirring and proceeding to the next process. In the high-concentration and low-water-activity phase, excess alkyl glycoside molecules form a dense bilayer or columnar micelle structure around the quaternary ammonium salt molecules. The hydrophilic head group of alkyl glycoside glucose is used to construct a hydrated steric hindrance layer that shields electrostatic attraction around the quaternary ammonium salt cation, physically locking the cationic charge in the micelle core.

[0029] In the preparation of the seaweed polysaccharide hydrated base solution, the aim is to construct a uniform and stable continuous phase carrier. The seaweed extract is dispersed in deionized water, using sodium alginate or fucoidan, with a viscosity of 1% aqueous solution of 100 mPa·s to 500 mPa·s. The solution is heated to 50°C to 60°C and stirred until the seaweed extract is completely hydrated and swollen, forming a clear base solution without particles. The pH of the base solution is adjusted to 6.0 to 7.5 to provide a charge environment for the compounding process.

[0030] In the shear-induced submerged dispersion and compounding process, to overcome the initial interfacial flocculation caused by excessively high local concentrations during mixing, a combination of dynamic flow control and high-shear dispersion is employed. The shearing equipment is activated, and the shear rate is set to 2500 rpm to 3500 rpm. The control of shear intensity in this process depends not only on the rotational speed but also on the micro-geometry of the shearing equipment. The high-shear region is specifically the narrow gap of 0.2 mm to 0.5 mm between the stator and rotor. To ensure that the high-viscosity shielding liquid is torn apart the moment it contacts the base liquid, the discharge port of the conduit must be precisely positioned, fixed 10 mm to 20 mm from the outer edge of the stator, and the discharge direction must align with the tangential direction of the base liquid's flow field to minimize turbulence. The disturbance disrupts the layered liquid crystal structure, creating a turbulent shear region in the substrate liquid. A high-viscosity, water-poor shielding liquid is continuously injected into this high-shear region via a conduit, submerged below the liquid surface. The injection rate is controlled at 2% to 5% of the total mass per minute. During the shear-induced immersion dispersion and composite step, the shear rate parameter is calibrated and amplified based on the stator outer edge linear velocity. Different rotor diameters (d) are measured in meters, and the shearing equipment speed (n) is measured in revolutions per minute. Based on the principle of constant linear velocity, the speed is calculated and set using the formula n = 60 × v / (π × d). The linear velocity v is controlled within the range of 18 to 25 meters per second, ensuring that the mechanical shear stress applied to the high-viscosity, water-poor shielding liquid is greater than the yield stress of the layered liquid crystal structure. The dynamic mass flux control formula Q... in =(M total ×γ) / t mix In the middle, Q in Defined as the instantaneous injection mass flow rate of the water-defense fluid, expressed in grams per minute; M total Defined as the total mass of the water-defense fluid, in grams; t mix The preset total injection time is defined in minutes. The dimensionless shear dispersion coefficient γ is determined using an inverse linear mapping procedure based on the initial viscosity of the shielding liquid. The viscosity η of the shielding liquid is measured using a rotational rheometer at 25 degrees Celsius and a reciprocal shear rate of 10 seconds. When η is in the range of 1000 mPa·s to 1200 mPa·s, γ is set to 1.0 to 1.2. When η exceeds 1200 mPa·s, γ is set to 0.8 to 1.0. This ensures that the injection flux and the fluid viscosity generate local flow resistance, maintaining the stability of the turbulent Reynolds number in the dispersion region. The high-viscosity layered liquid crystal structure is torn apart by mechanical force and dispersed into micron-sized particles. Due to the dilution effect brought about by the non-ionic protective layer and immersion injection, the cationic core is in a state of physical encapsulation by alkyl glycoside micelles at the moment of contact with the seaweed polysaccharide.

[0031] In the steady-state locking and post-treatment process, after the lean water shielding solution is evenly dispersed, the system temperature is lowered to below 30℃ to lock the microscopic micelle structure. Chelating agents, fragrances, and pH adjusters are added, and bubbles are removed under low-speed frame stirring at 40 to 60 rpm to obtain a detergent composition with a uniform appearance, transparency, and no visible suspended matter. The alkyl glycoside is preferably octyldecyl glucoside or dodecyl glucoside with a degree of polymerization of 1.1 to 1.3. The quaternary ammonium salt cationic bactericide is preferably dodecyl dimethyl benzyl ammonium chloride, disdecyl dimethyl ammonium chloride, or hexadecyl trimethyl ammonium chloride. Through this process, the quaternary ammonium salt cationic bactericide is encapsulated within the micromicelle core formed by the alkyl glycoside, while the seaweed extract is distributed in the continuous aqueous phase outside the micromicelles, achieving microscopic thermodynamic isolation. During use, it is diluted with water flow. Upon release, the critical micelle concentration equilibrium of the system is broken, and the encapsulated quaternary ammonium salt molecules dissociate and are released into the aqueous phase, restoring the ability to capture the negative charge on the surface of bacteria. The seaweed extract composite disinfectant detergent prepared by the method of this invention is a homogeneous transparent fluid with a viscosity stable between 500 mPa·s and 1500 mPa·s. To verify its thermodynamic stability, the finished product was subjected to a centrifugal accelerated destructive test (4000 rpm, 30 minutes), and the system did not undergo stratification or precipitation. At the same time, it underwent high and low temperature cycling tests from -5℃ to 45℃, and its appearance remained optically transparent. Microscopic characterization showed that the quaternary ammonium salt bactericide was firmly encapsulated in the micromicelle core formed by alkyl glycosides, and the seaweed extract was distributed in the continuous aqueous phase outside the micromicelles. The bactericide was only released when diluted for use, proving the effectiveness of the microscopic isolation mechanism in the preparation process.

[0032] Example 1: This example prepares a detergent that combines 99.9% sterilization rate with hand moisturizing function. Step 101: Construct a water-deficient layered liquid crystal shielding phase. In a 5L anchor-type stirred reactor with jacket and temperature control, add 1100g of octyldecyl glucoside (degree of polymerization 1.2, active ingredient content 50%) and 200g of dodecyl dimethyl benzyl ammonium chloride (active ingredient content 80%). After conversion, the molar ratio of alkyl glycoside to quaternary ammonium salt bactericide is approximately 5.5:1. The mass percentage of free water in the system from the raw materials is controlled at 45% (below the critical value of 55%). The temperature is set at 40℃, stirring is started, and the speed is set at 60 rpm. After stirring continuously for 45 minutes, the conductivity of the system is observed to drop to a stable plateau value, and online torque monitoring shows that the viscosity of the system rises to 1250 mPa·s. At this time, obvious anisotropic layered textures are visible under a polarizing microscope, indicating that the optically transparent water-deficient shielding liquid has been constructed. Step 102: Prepare Prepare a hydrated base solution of seaweed polysaccharides. Disperse 15g of sodium alginate (1% aqueous solution, viscosity 200mPa·s) uniformly in 2685g of deionized water. Turn on the heater and control the temperature at 55℃, continuously stirring until the sodium alginate is completely swollen and a clear, transparent base solution is formed. After cooling to room temperature, adjust the pH of the base solution to 6.8 to provide a preset charge environment for the composite process. Step 103: Shear-induced immersion dispersion composite. Turn on the pipeline high-shear device and set the shear rate to 3000 rpm to form a high-shear region with a linear velocity of approximately 22m / s in the base solution. Administer 1300g of the water-poor shielding liquid obtained in step 101 through a stainless steel conduit. Fix the outlet of the conduit 15mm from the outer edge of the stator of the shearing device, immersing the outlet 150mm below the surface of the base solution. This allows the shielding liquid to enter the high-shear gap tangentially along the flow field. Strictly control the injection rate using a variable frequency feed pump, referring to the specific formula. In this embodiment, the total mass 1300g, preset total injection time The time was 29 minutes and the shear dispersion coefficient was... Under the condition of 1.0, the injection rate was set to 45 g / min (approximately 3.5% / min of the total mass). During this process, the lamellar liquid crystal structure, due to its high viscosity, encapsulates the quaternary ammonium salt core. Upon entering the substrate liquid, it is mechanically torn into micron-sized micelles, isolating the direct contact between the quaternary ammonium salt cation and the sodium alginate anion chain segments. The system remains clear throughout the process, and no visible white flocculants or agglomerates are observed. In step 104, steady-state locking and post-treatment, after all the shielding liquid is injected, high shear is maintained for 5 minutes. Then, the temperature is lowered to below 30°C to lock the micelle structure. An appropriate amount of fragrance and chelating agent is added. Finally, the mixture is degassed by low-speed frame stirring at 50 rpm to obtain a final detergent product with a uniform and transparent appearance.

[0033] Example 2: This example aims to quantitatively verify the structural evolution of the aforementioned water-poor layered liquid crystal shielding phase under different free water contents by constructing a rigorous experimental system that includes gradient variables and environmental disturbances. The experiment was conducted in a 5L standardized pilot-scale reactor platform equipped with online viscosity monitoring (torque sensor accuracy 0.1 N·m) and in-situ particle size analysis probe (measurement range 0.01 μm to 1000 μm). The core logic of the experiment is to examine the regulatory effect of the key thermodynamic parameter of free water content on the microstructure of the shielding phase. The setting of free water content is based on the critical packing parameter theory of anisotropic self-assembly of surfactants: too high free water content will cause the system to tend to form loose spherical micelles, which cannot provide sufficient steric hindrance thickness to block long-range electrostatic attraction; while too low free water content may cause the system viscosity to be too high, exceeding the shear dispersion capability of industrial stirring equipment. Therefore, this experiment designed a set of gradient parameters across the critical phase transition point to determine the engineering boundary for maintaining the stable existence of the layered liquid crystal structure.

[0034] The experiment selected dodecyl dimethyl benzyl ammonium chloride as a cationic bactericide and octyldecyl glucoside (degree of polymerization 1.2) as a shielding agent, with a fixed molar ratio of 1:7. Four sample groups of the present invention were set up (numbered A1 to A4). The only variable was the percentage of free water in the system during the shielding phase construction stage, which were 40%, 50%, 55%, and 60%, respectively. A control sample group (numbered C1) was set up using a conventional dilute solution direct mixing process, in which the bactericide was not pre-constructed with the glycoside to form an aqueous-poor phase, but was directly dissolved in water. All sample groups were injected into the same sodium alginate (viscosity 200 mPas) base solution, and the shear rate during the injection process was kept constant at 3000 rpm. To simulate environmental interference in real application scenarios, standard hard water with a hardness of 300 ppm (calculated as CaCO3) was introduced as a dilution medium in the performance testing of the final product to verify the structural robustness and active release capability of the system under metal ion interference.

[0035] Table 1: Data on the structural characteristics of the shielding phase and the final performance response of the composition

[0036]

[0037] Referring to Table 1, the data shows a clear nonlinear structure-performance correlation. For control group C1, due to the lack of protection from the water-deficient shielding structure, the cationic bactericide undergoes intense electrostatic complexation upon contact with sodium alginate, leading to flocculation of the system. Furthermore, the bactericidal activity drops significantly to 42.5% because the active centers are pinned by the polysaccharide network. In groups A1 and A2, when the free water content is controlled at 50% or below, the shielding phase exhibits a typical anisotropic layered liquid crystal texture with high viscosity (>1400 mPa·s). This highly dense layered structure does not disintegrate during shear dispersion but forms stable microcapsule units, effectively isolating charge contact. This ensures the final product remains optically transparent and does not separate during centrifugation. Simultaneously, the high bactericidal rate under hard water conditions confirms that the liquid crystal structure... The structure can dissociate in response to concentration changes, releasing free bactericides. However, the data shows a clear performance inflection point in samples A3 to A4. When the free water content reaches 55% (A3), the layered texture begins to disintegrate, the system viscosity drops below 1000 mPa·s, and some cations escape, resulting in microemulsification and trace precipitation in the finished product. When the water content further increases to 60% (A4), the shielding phase is completely transformed into loose spherical micelles, losing its physical isolation ability, leading to severe flocculation and stratification and a decrease in bactericidal efficacy. In summary, the experimental results objectively confirm that a free water content below 55% is the critical thermodynamic condition for constructing an effective water-poor layered liquid crystal shielding phase. Within this range, the dense hydration layer formed by alkyl glycosides can resist the electrostatic capture of anionic polymers and the interference of hard water ions.

[0038] Example 3: This example combines Figures 1 to 4 The preparation method of a composite disinfectant detergent composition based on seaweed extract is described, such as... Figure 1As shown in the flowchart, this process flow diagram illustrates the entire preparation logic of the seaweed extract composite disinfectant detergent composition. It begins with two parallel pretreatment paths: on the left, alkyl glycosides are mixed with quaternary ammonium cationic bactericides, and under the conditions of controlling the free water content to be below 55% and the molar ratio to be 5:1 to 9:1, a high-viscosity, water-poor layered liquid crystal shielding phase with a dense hydration steric hindrance layer is constructed; on the right, seaweed extract is mixed with deionized water, stirred at 50°C to 60°C until completely swollen and dissolved, and the pH is adjusted to 6.0 to 7.5 to prepare a seaweed polysaccharide hydrated base solution. Both phases then enter a shear-induced process. The process involves an immersion dispersion compounding step, in which the water-defense liquid is regulated by a dynamic mass flux control module to maintain a local concentration higher than the critical micelle concentration and an injection rate of 2% to 5% per minute. It is then immersed in a high-shear region with a rotation speed of 2500 rpm to 3500 rpm to achieve physical isolation of charges and prevent flocculation. The process finally enters the steady-state locking and post-treatment stage, where the temperature is lowered to below 30°C, chelating agents and fragrances are added, and bubbles are removed by low-speed stirring. The final product is a detergent composition with a uniform and transparent appearance, no visible suspended matter, and thermodynamically stable coexistence of all components.

[0039] like Figure 2 As shown, the horizontal axis represents shearing time, ranging from 0 to 30 minutes, and the vertical axis represents D90 particle size, ranging from 0 to 55 μm. The figure contains three curves with different line shapes, corresponding to shearing conditions of 2500 rpm, 3000 rpm, and 3500 rpm, respectively. It shows that as the shearing time increases, the D90 particle size under all three conditions decreases exponentially from the initial 50 μm. Among them, the high shearing rate of 3500 rpm can reduce the particle size more quickly. Finally, after 20 minutes of shearing, all three curves tend to converge and stabilize in the micron range of 2 μm to 5 μm.

[0040] like Figure 3 As shown, the schematic diagram of the microstructure intuitively presents the thermodynamic state and spatial distribution of each component inside the composition. In the continuous aqueous background composed of dark seaweed polysaccharide segments, multiple micromicelle structures are suspended, with diameters ranging from approximately 50 nm to 65 nm. Each micromicelle consists of a central red sphere, i.e., the quaternary ammonium salt cationic bactericide core, and a blue ring-shaped region surrounding the core, i.e., the alkyl glycoside hydration shielding layer. This clearly shows that the alkyl glycoside achieves microscale spatial isolation between the cationic core and the seaweed polysaccharide anionic segments in the external environment by forming a dense physical barrier.

[0041] like Figure 4As shown, the process begins with the operator adding alkyl glycosides and quaternary ammonium salt bactericides in a molar ratio of 5:1 to 9:1 to the reaction vessel. The temperature is then set to 35°C to 45°C by the temperature control system and heated. The stirring system is then started to perform anchor stirring at 40 to 80 rpm. During the mixing process, the free water content is controlled to be below 55% to induce the formation of a liquid crystal structure. A monitoring cycle is then conducted for 30 to 60 minutes, during which the monitoring system provides real-time feedback on the system's viscosity, transmittance, and conductivity data. The process continues until the viscosity reaches 1000 mPa·s or higher, the transmittance exceeds 98%, and the conductivity tends to stabilize. This indicates the formation of anisotropic optical textured layered liquid crystals. Finally, an optically transparent, water-deficient shielding liquid is output, marking the completion of the shielding phase construction.

[0042] Example 4: In scaling up the preparation process of this invention from a laboratory scale to a ton-scale industrial production line, a standardized operating procedure based on online monitoring of process parameters was established. This procedure was implemented in a 2000L stainless steel reactor system equipped with an anchor-type stirring paddle (blade diameter d=0.8m) and a pipeline-type high-shear disperser (stator-rotor gap 0.5mm). For the construction process of the water-deficient layered liquid crystal shielding phase, the phase endpoint cannot be determined by visual transmittance in the industrial setting. Therefore, the stirring motor load torque and system conductivity were used as dual-coupled monitoring indicators. This was applied when alkyl glycosides and deca-hydroxymethyl ether... Dialkyldimethylbenzylammonium chloride was added to the mixing tank at the set molar ratio and with a free water content of 50%. The constant temperature stirring was then started. As the nonionic surfactant molecules gradually inserted into the gaps between the cationic head groups and formed an ordered layered liquid crystal structure, the migration of free ions in the system was restricted. At the same time, the fluid rheology changed from Newtonian fluid to pseudoplastic non-Newtonian fluid. Monitoring data showed that when the conductivity of the system dropped from the initial mixed state to the stable plateau period, and at the same time the load torque of the stirring motor increased exponentially and reached more than 95% of the steady-state value, it was determined that the dense water-deficient layered liquid crystal shielding structure was completed.

[0043] In the shear-induced dispersion and recombination stage, to avoid the uncertainty of scaling up solely based on rotational speed, the outer edge linear velocity of the stator and rotor is used as the core control parameter. Based on the high viscosity characteristics of the laminar liquid crystal phase (>1000 mPa·s), sufficient mechanical energy must be applied to overcome its yield stress and instantly tear it into micron-sized micelles. Experiments show that maintaining the outer edge linear velocity v of the stator and rotor at no less than 20 m / s is the critical physical condition to ensure that the shielding phase is effectively dispersed the instant it enters the base liquid. At this linear velocity, to prevent the locally high concentration of the shielding phase from contacting and flocculating with the surrounding sodium alginate before it can be dispersed, the mass injection flux Q of the shielding phase is... inThe effective dispersion volume of the shear chamber and the fluid renewal frequency are constraints. To quantify this constraint, a dynamic matching procedure is established: the ratio of instantaneous injection mass flow rate to main circulation flow rate is always kept below the critical threshold of 1:500. In actual operation, the feed rate of the shielding phase is precisely controlled by a variable frequency pump to link it with the working load of the high-shear disperser in real time. When abnormal fluctuations in the shear current or a decrease in the main circulation flow rate are detected, the control system automatically reduces the injection rate to ensure that each liquid crystal microcluster entering the high-shear region can obtain sufficient shearing and breaking energy and solvation dilution space. Through this control strategy of dynamic matching of flux shear capacity based on linear velocity, the laboratory-level micromicelle particle size distribution and macroscopic uniform transparency are successfully reproduced in a 2000L scale production, avoiding the risk of local gelation in large-scale production.

[0044] Example 5: This example establishes a standardized offline phase calibration and structure verification procedure. Before formal production, specific batches of alkyl glycosides and quaternary ammonium salt cationic bactericide raw materials are taken and a series of small samples are prepared according to the molar ratio range (5:1 to 9:1) and free water content gradient (40% to 60%). The microstructure of each sample is observed under constant temperature conditions using a polarizing microscope (POM). A qualified shielding phase must show a continuous mosaic or oily stripe texture under crossed polarized light, and there should be no isotropic dark areas or crystal precipitation. Furthermore, small-angle X-ray scattering (SAXS) analysis is performed on the samples that pass the initial screening. The interlayer spacing and long-range order of the layered structure are confirmed by the ratio of characteristic scattering peaks. Only when the SAXS spectrum shows clear 1:2:3 equidistant diffraction peaks and the interlayer spacing value meets the preset theoretical model range is the formula and process parameters confirmed as structurally compliant and approved for input into the production control system.

[0045] To address the deviation in shear dispersion efficiency caused by equipment geometric differences during industrial scale-up, a set of on-site shear parameter calibration procedures based on real-time particle size feedback was developed. This baseline calibration procedure must be performed every time a new high-shear dispersion device is put into use or the source of raw materials changes. The specific operation involves: during the circulation of the seaweed polysaccharide base solution, increasing the rotational speed of the shearing device in a stepwise manner, while simultaneously using an online laser particle size analyzer to monitor the particle size distribution index (PDI) and characteristic particle size D of the dispersed phase in the system in real time. 90 The evolution trend of the system, the goal of calibration is to find the critical shear power point above which the D of the system is... 90 The value can rapidly converge to below 5 micrometers within a specified cycle time, such as 15 minutes, and the PDI value is below 0.3. Once this critical point is determined, the control system will set the corresponding rotational speed and stator-rotor gap as the standard process parameters for the production line.

[0046] Example 6: This example establishes a standardized procedure for pre-calibration of raw material adaptability and dynamic compensation of process parameters. It requires that the baseline rheological properties be calibrated before each batch of seaweed extract is put into production. Specifically, a standard concentration of seaweed extract aqueous solution is prepared, and its properties are measured using a rotational rheometer at a constant temperature of 25°C within 0.1 s⁻¹. -1 up to 100s -1 Viscosity curves within the shear rate range; based on the calibration results, a dynamic compensation logic is established: if the measured viscosity is more than 10% higher than the reference value, then in the construction stage of the water-deficient layered liquid crystal shielding phase, the premixing temperature of the nonionic surfactant and cationic bactericide needs to be increased to the range of 45℃ to 50℃, and the low-speed stirring time needs to be extended to more than 60 minutes to ensure that the shielding phase can still obtain sufficient molecular arrangement freedom and dispersion uniformity in the higher viscosity substrate; conversely, if the measured viscosity is more than 10% lower than the reference value, then in the shear dispersion and compounding stage, the linear velocity of the stator and rotor outer edges needs to be increased to more than 25m / s, while the injection throughput needs to be reduced to 1.5% to 3% of the total mass per minute, to compensate for the reduced suspension stability due to the decrease in substrate viscosity by strengthening the mechanical shear and dilution effect.

[0047] In addition, to address the risk of phase drift that may be caused by temperature fluctuations in different seasons or production environments, a process window fine-tuning mechanism that adapts to ambient temperature is set up. When the ambient temperature is below 20°C, in order to prevent the water-deficient shielding phase from undergoing premature liquid crystal phase transition or viscosity surge due to cooling in the conveying pipeline, the pipeline heating system needs to be turned on to maintain the feed temperature in a constant temperature range of 35°C to 40°C. When the ambient temperature is above 30°C, in order to avoid the risk of seaweed polysaccharide degradation or microbial growth due to heat accumulation in the base liquid, the cooling circulation of the reactor jacket needs to be started to strictly control the system temperature during the compounding process to not exceed 35°C.

[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a composite disinfectant detergent composition based on seaweed extract, characterized in that, The method includes the following steps: Step 101: Construct a water-deficient layered liquid crystal shielding phase; In a reaction vessel equipped with temperature control and stirring functions, alkyl glycosides and quaternary ammonium cationic bactericides are mixed, and the molar ratio of alkyl glycosides to quaternary ammonium cationic bactericides is controlled to be 5:1 to 9:

1. The mass percentage of free water in the mixed system is controlled to be less than 55%, where free water is the sum of the water contained in the raw materials. The mixture is stirred at a rate of 40 to 80 revolutions per minute at 35 to 45 degrees Celsius until the viscosity of the system rises to more than 1000 mPa second, forming a layered liquid crystal structure with anisotropic optical texture, and obtaining an optically transparent water-deficient shielding liquid; Step 102: Prepare seaweed polysaccharide hydrated base solution; The seaweed extract was dispersed in deionized water, heated to 50 to 60 degrees Celsius, and stirred until the seaweed extract was completely swollen and dissolved to obtain a clear base solution. Step 103, shear-induced immersion dispersion and compounding; turn on the shearing device and set the shear rate to 2500 rpm to 3500 rpm to form a high-shear region in the base liquid. The water-deficient shielding liquid is continuously injected into the high-shear region through a conduit in a manner that is submerged below the liquid surface. The injection rate of the water-deficient shielding liquid is controlled to be 2% to 5% of the total mass per minute. During the injection process in step 103, the water-deficient shielding liquid maintains a layered liquid crystal structure to encapsulate the quaternary ammonium salt cationic bactericide and physically isolates the quaternary ammonium salt cationic bactericide from contact with the seaweed extract before it is dispersed and destroyed. In step 101, the alkyl glycoside is selected from octyldecyl glucoside or dodecyl glucoside and combinations thereof, with a degree of polymerization of 1.1 to 1.3; stirring is carried out for 30 to 60 minutes, and the transmittance of the mixture is monitored during stirring. When the transmittance exceeds 98% and the mixture exhibits shear-thinning fluid characteristics, the construction of the water-deficient layered liquid crystal shielding phase is determined to be complete; no additional process water is added throughout step 101. In step 101, the quaternary ammonium salt cationic bactericide is selected from dodecyl dimethyl benzyl ammonium chloride, decyl dimethyl ammonium chloride, or hexadecyl trimethyl ammonium chloride and combinations thereof; the hydrophilic head group of the alkyl glycoside in the water-poor shielding solution formed in step 101 forms a hydration layer around the cationic center of the quaternary ammonium salt cationic bactericide, and the hydration layer prevents the anionic chain segments in the seaweed extract from directly contacting the quaternary ammonium salt cationic bactericide during the shear dispersion process in step 103; In step 102, the seaweed extract is sodium alginate, and the viscosity of a 1% aqueous solution is 100 mPa second to 500 mPa second. Step 102 also includes adjusting the pH of the base solution to 6.0 to 7.

5. The pH adjustment is performed after the seaweed extract has completely swollen and before the compounding operation in step 103, so that the degree of ionization of the base solution during compounding is within a preset range. The preparation method also includes step 104, steady-state locking and post-treatment; step 104 includes: after all the water-defense liquid is injected and evenly dispersed, the system temperature is reduced to below 30 degrees Celsius; chelating agent, fragrance and pH adjuster are added in sequence; bubbles are removed under low-speed frame stirring conditions of 40 to 60 revolutions per minute until a finished detergent composition with uniform appearance and no visible suspended matter is obtained.

2. The method for preparing a seaweed extract composite disinfectant detergent composition according to claim 1, characterized in that, In step 103, the injection rate of the water-defense fluid follows the dynamic mass flux control formula: Q in =(M total ×γ) / t mix γ is taken as 0.8 to 1.2; the injection rate is controlled to keep the local concentration of the water-poor shielding liquid entering the high shear region higher than its critical micelle concentration, thus maintaining the integrity of the lamellar liquid crystal structure during the dispersion process.

3. The method for preparing a seaweed extract composite disinfectant detergent composition according to claim 2, characterized in that, In step 103, the high shear region is defined as the gap region between the stator and rotor of the shearing device, and the width of the gap region is 0.2 mm to 0.5 mm; the discharge port of the conduit is fixed at a position 10 mm to 20 mm away from the outer edge of the stator, and the direction of the discharge port is consistent with the tangential direction of the flow field of the base liquid.

4. The method for preparing a seaweed extract composite disinfectant detergent composition according to claim 1, characterized in that, The preparation method is used to prepare a transparent liquid detergent with a viscosity of 500 mPa·s to 1500 mPa·s; the transparent liquid detergent does not stratify after undergoing an accelerated destructive test of centrifugation at 4000 rpm for 30 minutes, and remains optically transparent after undergoing high and low temperature cycling tests from -5 degrees Celsius to 45 degrees Celsius; the quaternary ammonium salt cationic bactericide in the transparent liquid detergent exists in the form of physical encapsulation by alkyl glycoside micelles and is released into the aqueous phase during the dilution process.

5. The method for preparing a seaweed extract composite disinfectant detergent composition according to claim 1, characterized in that, In step 101, the reaction vessel is a stainless steel batching vessel with a jacketed temperature control device, and the stirring is carried out by an anchor-type stirring paddle; step 101 also includes detecting the change in conductivity of the system in the early stage of mixing. When the conductivity reading tends to stabilize and no longer fluctuates with the extension of stirring time, it is determined that the alkyl glycoside and the quaternary ammonium salt cationic bactericide have completed thermodynamic equilibrium assembly.

6. The seaweed extract compound disinfectant detergent composition prepared according to the method of claim 1, characterized in that, The composition is a homogeneous transparent fluid; the composition contains seaweed extract, quaternary ammonium salt cationic bactericide, alkyl glycoside and water; wherein the quaternary ammonium salt cationic bactericide is encapsulated in a micromicelle core formed by alkyl glycoside, and the seaweed extract is distributed in a continuous aqueous phase outside the micromicelle.

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