Robot simulation skin and preparation method thereof

Abstract

The invention discloses a robot simulation skin and a preparation method of the robot simulation skin. The formula of the robot simulation skin is composed of 100 parts of an organosilicon polymer with a main chain containing double bonds, 30-45 parts of a hyperbranched phenyl silicone oil plasticizer, 5-18 parts of a nanoscale texture conditioning agent, 7-22 parts of a dynamic crosslinking system and 1.5-9 parts of a function response additive. Through cross-scale cooperation of an organosilicon polymer matrix and functional components, a conformational entropy buffer network of a hyperbranched plasticizer is constructed on a molecular level, a light-force energy flow channel decoupling mechanism of a core-shell regulator is formed on a mesoscopic level, space-time regulation and control of gradient crosslinking and photo-thermal response are realized on a macroscopic level, and meanwhile, the cross-scale cross-linked hyperbranched polymer has good application prospects. The physical essence of inherent contradictions of'high-temperature softening-low-temperature embrittlement 'and'light transmittance-elasticity mutual exclusion' of existing silica gel skin is broken through, and the sensitivity of conformation entropy change to temperature is reduced through the molecular topology confinement effect.

Description

Technical Field

[0001] This invention belongs to the field of simulated skin technology, specifically relating to a robotic simulated skin; and more particularly to a method for preparing robotic simulated skin. Background Technology

[0002] With the increasing demands for interaction between artificial intelligence and the environment, robotic simulated skin, as a sensory interface, needs to possess human-like tactile sensitivity, environmental responsiveness, and mechanical durability. Currently, mainstream technologies use silicone-based materials to simulate the characteristics of biological skin, but systemic defects still exist.

[0003] Existing mechanisms of skin treatment often involve adding inorganic fillers to adjust firmness, but this leads to three major problems:

[0004] Low-temperature embrittlement / high-temperature creep: Conventional silicone oil plasticizers experience molecular chain freezing below -10℃ and irreversible plastic flow above 45℃;

[0005] Mechanical and optical properties are mutually exclusive: the plasticizing ratio that improves elasticity is negatively correlated with the optical requirement to reduce haze, making it impossible to achieve an ultra-soft touch with high light transmittance;

[0006] Lack of modulus gradient: Homogeneous materials are difficult to construct multi-layer modulus distributions for biological skin, leading to stress concentration under pressures above 300 kPa;

[0007] Therefore, we propose a robotic simulated skin and its preparation method, which effectively solves the problems raised in the existing technology. Summary of the Invention

[0008] The purpose of this invention is to provide a robotic simulated skin and its preparation method. Through cross-scale synergy between organosilicon polymer matrix and functional components, a conformational entropy buffer network of hyperbranched plasticizer is constructed at the molecular level, a light-mechanical energy flow channel decoupling mechanism of core-shell regulator is formed at the mesoscopic level, and temporal and terrestrial control of gradient crosslinking and photothermal response is achieved at the macroscopic level.

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

[0010] A robotic simulated skin, by weight, is composed of 100 parts of an organosilicon polymer with double bonds in the main chain, 30-45 parts of hyperbranched phenyl silicone oil plasticizer, 5-18 parts of nanoscale texture modifier, 7-22 parts of dynamic crosslinking system, and 1.5-9 parts of functional response additive.

[0011] The regulator consists of surface-modified titanium dioxide-coated mica sheets and thermoplastic polyurethane elastomer microspheres;

[0012] The dynamic crosslinking system consists of a platinum catalyst, a dicumyl peroxide complex, and vinyl-containing MQ silicone resin;

[0013] The functional responsive additive consists of a light stabilizer and a thermochromic microcapsule complex.

[0014] Preferably, the hyperbranched phenyl silicone oil plasticizer has a three-dimensional star topology, and its molecular skeleton is composed of a central phenylsiloxane core and a peripheral polydimethylsiloxane arm. The phenylsiloxane core contains 12-18 phenyl substituents and each phenyl ring has 2-3 methyl graft groups. The polydimethylsiloxane arm has a degree of polymerization of 25-40 and is terminally functionalized into a vinyl group.

[0015] The preparation of this plasticizer requires a two-step condensation reaction under argon protection: first, phenyltrichlorosilane and dimethyldichlorosilane are co-hydrolyzed in an ice bath at a molar ratio of 1:0.6-0.8 to generate a silanol-containing prepolymer; then, under platinum catalysis, hydrosilylation is carried out with terminal hydrogen-based polydimethylsiloxane, controlling the addition temperature at 75-85℃ and maintaining the viscosity of the reaction system in the range of 3000-5000 cP, finally yielding a hyperbranched product with a dynamic viscoelastic index of 0.35-0.55; this specific molecular configuration enables the plasticizer to maintain linear rheological properties in the temperature range of -20℃ to 60℃, effectively inhibiting the low-temperature embrittlement and high-temperature creep of the silicone matrix.

[0016] Preferably, the surface-modified titanium dioxide-coated mica sheets in the nanoscale texture modifier are prepared by atomic layer deposition process, wherein a 5-8 nm dense titanium dioxide layer and a 2-3 nm hydrophobic silane coupling agent layer are sequentially deposited on the surface of the mica substrate, wherein the titanium dioxide layer has an anatase phase with a crystal form of ≥85%, and the aspect ratio of the mica sheets is controlled in the range of 50:1 to 80:1 and the maximum lateral dimension is ≤500 nm;

[0017] Thermoplastic polyurethane elastomer microspheres are prepared by microfluidic emulsion polymerization of polycaprolactone diol and isophorone diisocyanate. The microsphere diameter exhibits a bimodal distribution: the main peak has a particle size of 15±3μm, accounting for 65-75%, and the secondary peak has a particle size of 45±8μm, accounting for 25-35%. The core of the microsphere is encapsulated with 0.5-1.2% by mass of phase change paraffin as a thermal expansion compensation medium. When the two are compounded, they need to undergo surface plasma treatment to achieve carboxyl-amino bonding, forming core-shell composite particles to synergistically regulate the tactile hardness and optical refractive index of silicone surface.

[0018] Preferably, the platinum catalyst and dicumyl peroxide complex in the dynamic cross-linking system are encapsulated using nanocapsule technology. The platinum catalyst is loaded onto a porous silica support and then encapsulated in a polymethyl methacrylate shell. The capsule particle size is 10-15 μm and the wall thickness is 1.5-2 μm.

[0019] Preferably, the light stabilizer in the functional response additive is a compound of a hindered amine compound and a benzotriazole ultraviolet absorber in a mass ratio of 2:1, wherein the hindered amine compound is poly(tetramethylpiperidine) succinate with an intrinsic viscosity ≥0.85 dL / g, and the benzotriazole compound is 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole with a melting point range of 101-105℃.

[0020] A method for preparing robotic simulated skin, the method comprising the following steps:

[0021] S1. Pre-dispersion treatment: Add 100 parts by weight of organosilicon polymer with double bonds in the main chain and 30-45 parts by weight of hyperbranched phenyl silicone oil plasticizer to a planetary mixer and mix for 10-15 minutes at 800-1200 rpm in an inert gas atmosphere, controlling the material temperature to ≤30℃.

[0022] S2, Gradient Addition: 5-18 parts by weight of nanoscale texture modifier are added to the pre-dispersed mixture in three stages, wherein:

[0023] In the first stage, surface-modified titanium dioxide coated mica sheets are added at a low speed of 200±50 rpm for 5 minutes.

[0024] The second stage switches to high-speed shear dispersion of thermoplastic polyurethane elastomer microspheres at 3000±200rpm for 8 minutes;

[0025] In the third stage, the mixture is remixed at 400±50 rpm for 10-15 minutes until the system transmittance is ≥85%.

[0026] S3, Dynamic Crosslinking: Inject 7-22 parts by weight of the dynamic crosslinking system via a peristaltic pump, transfer it to a twin-screw extruder, and run it under a barrel temperature gradient of 45℃→60℃→75℃ and a shear rate of 150-180s. -1 Reaction extrusion under certain conditions;

[0027] S4. Functional loading: Inject 1.5-9 parts by weight of functional response additive into the extruded material stream under a vacuum of -0.095MPa, and degas for 30 minutes;

[0028] S5, Gradient Dynamic Curing: Inject the mixture into the biomimetic mold and execute:

[0029] First stage: Maintain a constant temperature of 40-50℃ for 20-30 minutes, and apply ultrasonic vibration with an amplitude of 5-10kHz.

[0030] Second stage: Increase the temperature to 85℃ at a rate of 0.5℃ / min, and pressurize to 0.5-2MPa and maintain for 45 minutes;

[0031] Third stage: After being rapidly cooled to -20℃ with liquid nitrogen, the temperature is allowed to rise naturally to 25℃ before demolding.

[0032] Preferably, the twin-screw extruder is equipped with a molecular orientation device, comprising:

[0033] Conical flow channel module: inlet diameter 25mm tapers to outlet diameter 8mm, length-to-diameter ratio 18:1;

[0034] Rotating magnetic field generator: Apply an axial magnetic field of 0.5-1.2T to the extrusion section, with the magnetic field lines forming a 15° angle with the extrusion direction;

[0035] Electrostatic sorting screen: a nickel-titanium alloy screen with a mesh diameter of 50μm superimposed with an electric field of 500V / cm;

[0036] Among them, the surface-modified titanium dioxide-coated mica sheets are oriented along the extrusion direction under the action of a magnetic field, and the thermoplastic polyurethane elastomer microspheres are radially distributed due to the difference in surface charge when passing through the electrostatic net: the positively charged phase change microspheres migrate to the near-wall region to form an elastic buffer layer, and the negatively charged microspheres accumulate in the central region to construct an isotropic matrix, thereby realizing the in-situ self-assembly of nanoparticles.

[0037] Preferably, the incorporation of the nanoscale texture modifier includes an in-situ modification step:

[0038] First, the thermoplastic polyurethane elastomer microspheres were plasma activated: treated for 10 minutes in an argon / oxygen mixed atmosphere at a volume ratio of 4:1 and a power of 100W, to increase the surface carboxyl group density to 35-40 groups / μm. 2 ;

[0039] Surface-modified titanium dioxide-coated mica sheets were dispersed in an ethanol solution containing 0.3 wt% silane coupling agent and ultrasonically treated to form a modified layer.

[0040] During the third stage of compounding, 0.5-2 parts by weight of a double-terminated amino polysiloxane bridging agent are added to form a core-shell structure through amide bonding. The bonding reaction temperature is controlled at 60±2℃.

[0041] Preferably, it also includes post-curing photoresponse conditioning, whereby the simulated skin undergoes UV-Vis synergistic treatment after demolding:

[0042] First, at a wavelength of 365nm and an irradiance of 12mW / cm²... 2 Exposure to ultraviolet light for 5 minutes triggers a crystal transformation in the thermochromic microcapsules;

[0043] Subsequently, the irradiance was treated with gradient illumination in the visible spectrum range of 400-700 nm, starting from 0.1 W / cm². 2 Increased to 1.5W / cm 2Simultaneous infrared thermal imaging monitors surface temperature changes, and airflow cooling is activated when the temperature reaches 32±0.5℃;

[0044] The illumination mode uses fiber optic matrix scanning and positioning, with a spot diameter of 50μm and a spacing of 200μm, forming a micro-region phase transition lattice with a coverage of 75%.

[0045] The technical effects and advantages of this invention are as follows:

[0046] The three-dimensional star structure of hyperbranched phenyl silicone oil plasticizer forms a molecular chain conformation entropy compensation network through the rigid support of phenyl groups and the dynamic entanglement of siloxane arms. This network simultaneously suppresses the brittle transition energy caused by low-temperature molecular chain freezing and the viscous dissipation energy caused by high-temperature molecular slippage, thus achieving wide-temperature-range elastic stability from the perspective of molecular kinematics.

[0047] The core-shell interface of the nanoscale texture modifier constructs an "optical-mechanical converter". The hard core reduces the entropy increase of incident light scattering through the optical waveguide effect of anatase phase titanium dioxide, while the soft shell phase change paraffin thermal energy storage absorbs elastic deformation energy, realizing the physical channel separation of visible light transmittance and compressive deformation energy. Detailed Implementation

[0048] 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. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. 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.

[0049] This invention proposes a robotic simulated skin and its preparation method. Through cross-scale synergy between organosilicon polymer matrix and functional components, a conformational entropy buffer network of hyperbranched plasticizer is constructed at the molecular level, a light-mechanical energy flow channel decoupling mechanism of core-shell regulator is formed at the mesoscopic level, and temporal and genomic control of gradient crosslinking and photothermal response is achieved at the macroscopic level.

[0050] This technology breaks through the inherent physical contradictions of existing silicone skin, namely "high-temperature softening-low-temperature embrittlement" and "transmittance-elasticity mutual repulsion." It utilizes the molecular topological confinement effect to reduce the sensitivity of conformational entropy change to temperature, overcomes photoelastic energy coupling based on the core-shell interface refractive index-modulus dual-channel regulation theory, achieves spatial homogenization of crosslinking density through staged crosslinking reaction kinetics, and achieves millisecond-level environmental response through the micro-region photon-lattice vibration coupling mechanism. Ultimately, without the intervention of external control devices, the bionic skin possesses environmental self-adaptation capabilities, establishing a life-like system building block for robotic tactile perception with autonomous energy circulation.

[0051] Specifically, by weight, the formulation of the robot's simulated skin consists of 100 parts of a main chain organosilicon polymer containing double bonds, 30-45 parts of hyperbranched phenyl silicone oil plasticizer, 5-18 parts of nanoscale texture modifier, 7-22 parts of dynamic crosslinking system, and 1.5-9 parts of functional response additive.

[0052] The regulator consists of surface-modified titanium dioxide-coated mica sheets and thermoplastic polyurethane elastomer microspheres;

[0053] The dynamic crosslinking system consists of a platinum catalyst, a dicumyl peroxide complex, and vinyl-containing MQ silicone resin;

[0054] The functional responsive additive consists of a light stabilizer and a thermochromic microcapsule complex.

[0055] It should be noted that the hyperbranched phenyl silicone oil plasticizer has a three-dimensional star topology. Its molecular skeleton consists of a central phenylsiloxane core and an outer polydimethylsiloxane arm. The phenylsiloxane core contains 12-18 phenyl substituents and each phenyl ring has 2-3 methyl graft groups. The polydimethylsiloxane arm has a degree of polymerization of 25-40 and is terminally functionalized into a vinyl group.

[0056] The preparation of this plasticizer requires a two-step condensation reaction under argon protection: first, phenyltrichlorosilane and dimethyldichlorosilane are co-hydrolyzed in an ice bath at a molar ratio of 1:0.6-0.8 to generate a silanol-containing prepolymer; then, under platinum catalysis, hydrosilylation is carried out with terminal hydrogen-based polydimethylsiloxane, controlling the addition temperature at 75-85℃ and maintaining the viscosity of the reaction system in the range of 3000-5000 cP, finally yielding a hyperbranched product with a dynamic viscoelastic index of 0.35-0.55; this specific molecular configuration enables the plasticizer to maintain linear rheological properties in the temperature range of -20℃ to 60℃, effectively inhibiting the low-temperature embrittlement and high-temperature creep of the silicone matrix.

[0057] The surface-modified titanium dioxide-coated mica sheets in the nanoscale texture modifier are prepared using atomic layer deposition (ALD). A 5-8 nm dense titanium dioxide layer and a 2-3 nm hydrophobic silane coupling agent layer are sequentially deposited on the mica substrate surface. The titanium dioxide layer has an anatase phase content of ≥85%, and the mica sheet diameter-to-thickness ratio is controlled within the range of 50:1 to 80:1 with a maximum lateral dimension ≤500 nm. The thermoplastic polyurethane elastomer microspheres are prepared by microfluidic emulsion polymerization of polycaprolactone diol and isophorone diisocyanate. The microsphere diameter exhibits a bimodal distribution: the main peak has a particle size of 15±3 μm, accounting for 65-75%, and the secondary peak has a particle size of 45±8 μm, accounting for 25-35%. The microsphere core is encapsulated with 0.5-1.2% by mass of phase change paraffin as a thermal expansion compensation medium. When the two are compounded, surface plasma treatment is required to achieve carboxyl-amino bonding, forming core-shell composite particles to synergistically regulate the tactile hardness and optical refractive index of silicone surface.

[0058] In the dynamic crosslinking system, the platinum catalyst and dicumyl peroxide complex are encapsulated using nanocapsule technology. The platinum catalyst is supported on a porous silica carrier and then encapsulated in a polymethyl methacrylate shell, with a capsule particle size of 10-15 μm and a wall thickness of 1.5-2 μm. The dicumyl peroxide is dispersed in a silicone oil medium to form microemulsion droplets with a particle size of 0.5-2 μm. The mass ratio of the two is in the range of 3:7 to 4:6, and they are activated in stages through controlled-release membranes: at 40-60℃, the microcapsules rupture to release the peroxide and initiate primary crosslinking; at 80-100℃, the polymethyl methacrylate shell melts and releases the platinum catalyst to trigger secondary crosslinking. The vinyl-containing MQ silicone resin has a vinyl functionality of 1.8-2.2 mmol / g and a molecular weight distribution index ≤1.3. In the crosslinking network formed by the resin and the organosilicon polymer, each 100 silicon atoms contain 8-12 ladder-shaped structural nodes.

[0059] The light stabilizer in the functional response additive is a compound of hindered amine and benzotriazole UV absorbers in a mass ratio of 2:1. The hindered amine is poly(tetramethylpiperidine) succinate with an intrinsic viscosity ≥0.85 dL / g, and the benzotriazole is 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole with a melting point range of 101-105℃. The thermochromic microcapsules are prepared by interfacial polymerization. The core contains crystal violet lactone as an electron donor, bisphenol A as a proton donor, and tetradecyl alcohol as a solvent. The capsule wall is a melamine-formaldehyde copolymer with a thickness of 300-500 nm, and the phase transition temperature is precisely controlled at 32±0.5℃. When the two are combined, a 20-30 nm thick light stabilizer coating is formed on the surface of the thermochromic microcapsules through electrostatic self-assembly, achieving a synergistic effect of photothermal dual response.

[0060] Furthermore, the preparation method of the above composition is as follows:

[0061] S1. Pre-dispersion treatment: Add 100 parts by weight of organosilicon polymer with double bonds in the main chain and 30-45 parts by weight of hyperbranched phenyl silicone oil plasticizer to a planetary mixer and mix for 10-15 minutes at 800-1200 rpm in an inert gas atmosphere, controlling the material temperature to ≤30℃.

[0062] S2, Gradient Addition: 5-18 parts by weight of nanoscale texture modifier are added to the pre-dispersed mixture in three stages, wherein:

[0063] In the first stage, surface-modified titanium dioxide coated mica sheets are added at a low speed of 200±50 rpm for 5 minutes.

[0064] The second stage switches to high-speed shear dispersion of thermoplastic polyurethane elastomer microspheres at 3000±200rpm for 8 minutes;

[0065] In the third stage, the mixture is remixed at 400±50 rpm for 10-15 minutes until the system transmittance is ≥85%.

[0066] The incorporation of nanoscale texture modifiers includes an in-situ modification step:

[0067] First, the thermoplastic polyurethane elastomer microspheres were plasma activated: treated for 10 minutes in an argon / oxygen mixed atmosphere at a volume ratio of 4:1 and a power of 100W, to increase the surface carboxyl group density to 35-40 groups / μm. 2 ;

[0068] Surface-modified titanium dioxide-coated mica sheets were dispersed in an ethanol solution containing 0.3 wt% silane coupling agent and ultrasonically treated to form a modified layer.

[0069] During the third stage of compounding, 0.5-2 parts by weight of a double-terminated amino polysiloxane bridging agent are added to form a core-shell structure through amide bonding. The bonding reaction temperature is controlled at 60±2℃.

[0070] S3, Dynamic Crosslinking: Inject 7-22 parts by weight of the dynamic crosslinking system via a peristaltic pump, transfer it to a twin-screw extruder, and run it under a barrel temperature gradient of 45℃→60℃→75℃ and a shear rate of 150-180s. -1 Reaction extrusion under certain conditions;

[0071] S4. Functional Loading: Inject 1.5-9 parts by weight of the functional response additive into the extruded material stream under a vacuum of -0.095 MPa, followed by degassing for 30 minutes; the degassing process includes low-frequency mechanical oscillation coupled with a vacuum gradient.

[0072] For the first 15 minutes: a 10Hz sinusoidal wave vibration was applied under a vacuum of -0.095MPa with an acceleration amplitude of 0.5g;

[0073] The following 15 minutes: The voltage drops in three segments (-0.095→-0.08→-0.05MPa) and is superimposed with triangular wave oscillations with increasing frequency (10→20→30Hz);

[0074] The bubble precipitation rate satisfies:

[0075] Where ΔP is the vacuum pressure difference, μ is the system viscosity, and T is the absolute temperature.

[0076] S5, Gradient Dynamic Curing: Inject the mixture into the biomimetic mold and execute:

[0077] First stage: Maintain a constant temperature of 40-50℃ for 20-30 minutes, and apply ultrasonic vibration with an amplitude of 5-10kHz; the ultrasonic vibration in the first stage satisfies the following control law:

[0078] The amplitude A0 = 20 ± 5 μm, and the frequency f changes continuously in a sweeping mode between 5 and 10 kHz.

[0079] Second stage: Increase the temperature to 85℃ at a rate of 0.5℃ / min, and pressurize to 0.5-2MPa and maintain for 45 minutes;

[0080] Third stage: After being rapidly cooled to -20℃ with liquid nitrogen, the temperature is allowed to rise naturally to 25℃ before demolding.

[0081] This also includes post-curing photoresponse conditioning, which involves UV-Vis synergistic treatment of the simulated skin after demolding.

[0082] First, at a wavelength of 365nm and an irradiance of 12mW / cm²... 2 Exposure to ultraviolet light for 5 minutes triggers a crystal transformation in the thermochromic microcapsules;

[0083] Subsequently, the irradiance was treated with gradient illumination in the visible spectrum range of 400-700 nm, starting from 0.1 W / cm². 2 Increased to 1.5W / cm 2 Simultaneous infrared thermal imaging monitors surface temperature changes, and airflow cooling is activated when the temperature reaches 32±0.5℃;

[0084] The illumination mode uses fiber optic matrix scanning and positioning, with a spot diameter of 50μm and a spacing of 200μm, forming a micro-region phase transition lattice with a coverage of 75%.

[0085] Example 1

[0086] Component characteristics: Hyperbranched phenyl silicone oil plasticizer: m = 1.2 (high phenyl content), n = 35 (long chain arms); Nanoscale texture modifier: Rt = 1.25 (mica flakes: microspheres = 5:4); Dynamic crosslinking system: peroxide / platinum catalyst mass ratio 3.5:6.5;

[0087] Preparation process parameters: Gradient curing first stage: 45℃ + 8kHz ultrasound (amplitude 25μm); Molecular orientation device: axial magnetic field strength 0.8T;

[0088] The effect is to achieve a linear elastic response within a temperature range of -25℃ to 65℃:

[0089] The impact resistance in the low-temperature range (-25℃) is increased to 3.2 times that of conventional silicone, with no cracks generated;

[0090] The compression set in the high-temperature zone (65℃) is reduced to below 5%;

[0091] Transmittance fluctuation range ≤ ±3% (baseline value 82%).

[0092] Example 2

[0093] Component characteristics: Nanoscale texture modifier: Rt=1.5 (mica sheet accounts for 60%), titanium dioxide coating thickness 6nm (anatase phase 92%), microsphere bimodal distribution: main peak 12μm (70%), secondary peak 40μm (30%), functional response additive: light stabilizer / thermochromic capsule mass ratio 3:1;

[0094] Preparation process parameters: Gradient dispersion stage 3: Add 1.5 parts of double-terminated amino polysiloxane (bonding at 60℃); Post-curing treatment: UV exposure + gradient visible light irradiation (0.1→1.0W / cm²). 2 );

[0095] Effectiveness, overcoming the bottleneck of mutually exclusive optical and mechanical properties:

[0096] With a visible light transmittance of 85%, it achieves a Shore hardness of 00 to 45 (regular products ≤60%).

[0097] Surface haze was reduced to 8% (better than the average 12% of biological skin);

[0098] Fingerprint-level texture resolution: capable of reproducing groove structures 50μm wide × 10μm deep.

[0099] Example 3

[0100] Component characteristics: Functional response additive: contains a light response adjustment coefficient of σ = 0.25; Dynamic cross-linking system: platinum catalyst microcapsule wall thickness 1.8 μm;

[0101] Preparation process: Curing pressure curve: piecewise function was used; microfluidic mold cooling: S = 250 cm⁻¹ 2 The hot oil flow rate Q = 1.8 L / min, and the optical response conditioning is: 80% fiber optic array coverage.

[0102] Results, millisecond-level dynamic environment adaptability:

[0103] Temperature change response (25℃→40℃): tactile hardness adjustment time ≤0.8s;

[0104] Light intensity threshold triggering (>10klux): thermochromic response time <50ms;

[0105] Pressure-tactile signal conversion: Sensing delay ≤25ms under 10N load;

[0106] The specific embodiments described above are shown in the table below:

[0107]

[0108] Based on the above, Example 1: Adaptability to Extreme Environments

[0109] A rigid-flexible biphase network was constructed at the molecular level using a plasticizer with a high phenyl content (m = 1.2) and a precise Rt ratio (1.25).

[0110] Low-temperature toughness: The phenyl group inhibits molecular chain freezing, and the impact strength at -25℃ is 3.2 times that of the conventional type.

[0111] High-temperature stability: The long siloxane arms (n=35) absorb creep energy, and the permanent deformation rate at 65℃ is <5%.

[0112] Optical uniformity: The mica sheets are oriented and aligned by an axial magnetic field (0.8T), with transmittance fluctuation ≤3%.

[0113] Example 2: Super-resolution biomimetic structure

[0114] Optical manipulation based on anatase TiO2 (92%) and bimodal microsphere size matching (12μm / 40μm):

[0115] Photoelastic decoupling: A 6nm TiO2 coating layer achieves total internal reflection loss reduction, reducing hardness to 45 (level 00) at 85% transmittance.

[0116] Texture replication: Main peak microspheres fill the macroscopic contour, and secondary peak microspheres reconstruct micron-level grooves (50×10μm).

[0117] Photothermal Synergy: UV-Visible Light Gradient Irradiation Triggers Microcapsule Lattice Reorganization, Achieving Haze as Low as 8%

[0118] Example 3: Intelligent Dynamic Response

[0119] Employing a quantum-based adjustment system with σ = 0.25 and millisecond-level fixed control:

[0120] Temperature-adaptive design: Piecewise pressure curve matched to phase transition energy barrier, response <0.8s from 25℃ to 40℃.

[0121] Optomechanical linkage: Localized excitation of electron transitions in a fiber optic array (80% coverage), with a photoresponse of <50ms.

[0122] Neuromorphic conduction: Thin-walled catalyst capsules (1.8 μm) accelerate cross-linked mesh reconstruction with sensing delay ≤25 ms.

[0123] In summary, the present invention has the following effects:

[0124] Molecular topological entropy buffering effect

[0125] The three-dimensional star structure of hyperbranched phenyl silicone oil plasticizer forms a molecular chain conformation entropy compensation network through the rigid support of phenyl groups and the dynamic entanglement of siloxane arms. This network simultaneously suppresses the brittle transition energy caused by low-temperature molecular chain freezing and the viscous dissipation energy caused by high-temperature molecular slippage, thus achieving wide-temperature-range elastic stability from the perspective of molecular kinematics.

[0126] Core-shell structure photoelastic decoupling mechanism

[0127] The core-shell interface of the nanoscale texture modifier (mica sheet hard core / elastic microsphere soft shell) constructs an "optical-mechanical converter". The hard core reduces the entropy increase of incident light scattering through the optical waveguide effect of anatase phase titanium dioxide, while the phase change paraffin thermal energy storage of the soft shell absorbs elastic deformation energy, realizing the physical channel separation of visible light transmittance and compressive deformation energy.

[0128] Spatiotemporal gradient crosslinking dynamics

[0129] The phased controlled release of the dynamic crosslinking system (peroxide primary crosslinking → platinum-catalyzed secondary crosslinking) establishes a dynamic balance between the free radical reaction rate and the diffusion rate, enabling the crosslinking network to form a density gradient distribution of trapezoidal structural nodes and linear segments in the spatial dimension, and to complete the energy dissipation of stress relaxation and crosslinking curing in the temporal dimension.

[0130] Micro-region phase transition energy field coupling mechanism

[0131] Functional responsive additives convert photonic quantum energy into the driving force to overcome the phase transition interface energy barrier by inducing thermochromic crystal transformation under ultraviolet light and reconstructing the micro-region temperature field driven by visible light. This enables phonon-exciton coupling oscillation at megahertz frequency in the fiber positioning array, breaking through the molecular diffusion rate limitation of traditional photothermal response.

[0132] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A robotic simulated skin, characterized in that, By weight, the formulation of the robot's simulated skin consists of 100 parts of a main chain organosilicon polymer containing double bonds, 30-45 parts of hyperbranched phenyl silicone oil plasticizer, 5-18 parts of nanoscale texture modifier, 7-22 parts of dynamic crosslinking system, and 1.5-9 parts of functional response additive. The regulator consists of surface-modified titanium dioxide-coated mica sheets and thermoplastic polyurethane elastomer microspheres; The dynamic crosslinking system consists of a platinum catalyst, a dicumyl peroxide complex, and vinyl-containing MQ silicone resin; The functional responsive additive consists of a light stabilizer and a thermochromic microcapsule complex.

2. The robotic simulated skin according to claim 1, characterized in that, Hyperbranched phenyl silicone oil plasticizer has a three-dimensional star topology. Its molecular skeleton consists of a central phenylsiloxane core and an outer polydimethylsiloxane arm. The phenylsiloxane core contains 12-18 phenyl substituents and each phenyl ring has 2-3 methyl graft groups. The polydimethylsiloxane arm has a degree of polymerization of 25-40 and is terminally functionalized into vinyl groups. The preparation of this plasticizer requires a two-step condensation reaction under argon protection: first, phenyltrichlorosilane and dimethyldichlorosilane are co-hydrolyzed in an ice bath at a molar ratio of 1:0.6-0.8 to generate a silanol-containing prepolymer; then, under platinum catalysis, hydrosilylation is carried out with terminal hydrogen-based polydimethylsiloxane, controlling the addition temperature at 75-85℃ and maintaining the viscosity of the reaction system in the range of 3000-5000 cP, finally yielding a hyperbranched product with a dynamic viscoelastic index of 0.35-0.55; this specific molecular configuration enables the plasticizer to maintain linear rheological properties in the temperature range of -20℃ to 60℃, effectively inhibiting the low-temperature embrittlement and high-temperature creep of the silicone matrix.

3. The robotic simulated skin according to claim 1, characterized in that, The surface-modified titanium dioxide-coated mica sheets in the nanoscale texture modifier are prepared by atomic layer deposition. A 5-8 nm dense titanium dioxide layer and a 2-3 nm hydrophobic silane coupling agent layer are sequentially deposited on the surface of the mica substrate. The titanium dioxide layer has an anatase phase with a crystal structure of ≥85%. The aspect ratio of the mica sheets is controlled in the range of 50:1 to 80:1 and the maximum lateral dimension is ≤500 nm. Thermoplastic polyurethane elastomer microspheres are prepared by microfluidic emulsion polymerization of polycaprolactone diol and isophorone diisocyanate. The microsphere diameter exhibits a bimodal distribution: the main peak has a particle size of 15±3μm, accounting for 65-75%, and the secondary peak has a particle size of 45±8μm, accounting for 25-35%. The core of the microsphere is encapsulated with 0.5-1.2% by mass of phase change paraffin as a thermal expansion compensation medium. When the two are compounded, they need to undergo surface plasma treatment to achieve carboxyl-amino bonding, forming core-shell composite particles to synergistically regulate the tactile hardness and optical refractive index of silicone surface.

4. The robotic simulated skin according to claim 1, characterized in that, The platinum catalyst and dicumyl peroxide complex in the dynamic cross-linking system are encapsulated using nanocapsule technology. The platinum catalyst is loaded onto a porous silica support and then encapsulated in a polymethyl methacrylate shell. The capsules have a particle size of 10-15 μm and a wall thickness of 1.5-2 μm.

5. The robotic simulated skin according to claim 1, characterized in that, The light stabilizer in the functional response additive is a compound of hindered amine compound and benzotriazole UV absorber in a mass ratio of 2:

1. The hindered amine compound is poly(tetramethylpiperidine) succinate with an intrinsic viscosity ≥0.85dL / g, and the benzotriazole compound is 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole with a melting point range of 101-105℃.

6. A method for preparing robotic simulated skin, characterized in that, The method is used to prepare the robotic simulated skin according to any one of claims 1-5, and includes the following steps: S1. Pre-dispersion treatment: Add 100 parts by weight of organosilicon polymer with double bonds in the main chain and 30-45 parts by weight of hyperbranched phenyl silicone oil plasticizer to a planetary mixer and mix for 10-15 minutes at 800-1200 rpm in an inert gas atmosphere, controlling the material temperature to ≤30℃. S2, Gradient Addition: 5-18 parts by weight of nanoscale texture modifier are added to the pre-dispersed mixture in three stages, wherein: In the first stage, surface-modified titanium dioxide coated mica sheets are added at a low speed of 200±50 rpm for 5 minutes. The second stage switches to high-speed shear dispersion of thermoplastic polyurethane elastomer microspheres at 3000±200rpm for 8 minutes; In the third stage, the mixture is remixed at 400±50 rpm for 10-15 minutes until the system transmittance is ≥85%. S3, Dynamic Crosslinking: Inject 7-22 parts by weight of the dynamic crosslinking system via a peristaltic pump, transfer it to a twin-screw extruder, and run it under a barrel temperature gradient of 45℃→60℃→75℃ and a shear rate of 150-180s. -1 Reaction extrusion under certain conditions; S4. Functional loading: Inject 1.5-9 parts by weight of functional response additive into the extruded material stream under a vacuum of -0.095MPa, and degas for 30 minutes; S5, Gradient Dynamic Curing: Inject the mixture into the biomimetic mold and execute: First stage: Maintain a constant temperature of 40-50℃ for 20-30 minutes, and apply ultrasonic vibration with an amplitude of 5-10kHz. Second stage: Increase the temperature to 85℃ at a rate of 0.5℃ / min, and pressurize to 0.5-2MPa and maintain for 45 minutes; Third stage: After being rapidly cooled to -20℃ with liquid nitrogen, the temperature is allowed to rise naturally to 25℃ before demolding.

7. The method for preparing robotic simulated skin according to claim 6, characterized in that, The twin-screw extruder is equipped with a molecular orientation device, comprising: Conical flow channel module: inlet diameter 25mm tapers to outlet diameter 8mm, length-to-diameter ratio 18:1; Rotating magnetic field generator: Apply an axial magnetic field of 0.5-1.2T to the extrusion section, with the magnetic field lines forming a 15° angle with the extrusion direction; Electrostatic sorting screen: a nickel-titanium alloy screen with a mesh diameter of 50μm superimposed with an electric field of 500V / cm; Among them, the surface-modified titanium dioxide-coated mica sheets are oriented along the extrusion direction under the action of a magnetic field, and the thermoplastic polyurethane elastomer microspheres are radially distributed due to the difference in surface charge when passing through the electrostatic net: the positively charged phase change microspheres migrate to the near-wall region to form an elastic buffer layer, and the negatively charged microspheres accumulate in the central region to construct an isotropic matrix, thereby realizing the in-situ self-assembly of nanoparticles.

8. The method for preparing robotic simulated skin according to claim 6, characterized in that, The incorporation of nanoscale texture modifiers includes an in-situ modification step: First, the thermoplastic polyurethane elastomer microspheres were plasma activated: treated for 10 minutes in an argon / oxygen mixed atmosphere at a volume ratio of 4:1 and a power of 100W, to increase the surface carboxyl group density to 35-40 groups / μm. 2 ; Surface-modified titanium dioxide-coated mica sheets were dispersed in an ethanol solution containing 0.3 wt% silane coupling agent and ultrasonically treated to form a modified layer. During the third stage of compounding, 0.5-2 parts by weight of a double-terminated amino polysiloxane bridging agent are added to form a core-shell structure through amide bonding. The bonding reaction temperature is controlled at 60±2℃.

9. The method for preparing robotic simulated skin according to claim 6, characterized in that, This also includes post-curing photoresponse conditioning, which involves UV-Vis synergistic treatment of the simulated skin after demolding. First, at a wavelength of 365nm and an irradiance of 12mW / cm²... 2 Exposure to ultraviolet light for 5 minutes triggers a crystal transformation in the thermochromic microcapsules; Subsequently, the irradiance was treated with gradient illumination in the visible spectrum range of 400-700 nm, starting from 0.1 W / cm². 2 Increased to 1.5W / cm 2 Simultaneous infrared thermal imaging monitors surface temperature changes, and airflow cooling is activated when the temperature reaches 32±0.5℃; The illumination mode uses fiber optic matrix scanning and positioning, with a spot diameter of 50μm and a spacing of 200μm, forming a micro-region phase transition lattice with a coverage of 75%.

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