Temperature-sensitive molding mud and preparation method thereof

Abstract

The invention discloses temperature-sensitive molding mud and a preparation method thereof, and relates to the technical field of molding materials, the molding mud comprises the following raw materials by weight: A: 55-65 parts of beeswax; b: 15-20 parts of edible wax oil; c: 8-12 parts of edible vegetable oil; d: 50-75 parts of edible starch; e: 1-3 parts of food coloring; the preparation method of the molding mud comprises the following steps: raw material pretreatment: crushing blocky beewax with the melting point of 62-65 DEG C into particles with the particle size of less than or equal to 2mm, and adopting a low-temperature crusher with the working temperature of less than or equal to 10 DEG C to prevent adhesion; sieving the edible-grade starch with water less than or equal to 12% and 50-100 meshes, drying in an oven at 60 DEG C for 2 hours, and controlling the final water less than or equal to 5%; the melting point of the wax oil is 30-35 DEG C, the wax oil and the vegetable oil are premixed in proportion, heated to 40 DEG C and stirred for 10 minutes to be in a uniform liquid state.

Description

Technical Field

[0001] The present invention relates to the technical field of modeling materials, in particular to a temperature-sensitive modeling clay and a preparation method thereof. Background Art

[0002] Traditional plastic materials (such as clay, plasticine, and industrial clay) are widely used in artistic creation, industrial models, and education, but they have the following significant drawbacks:

[0003] Irreversible hardening and poor repeatability: Industrial sludge: contains paraffin, sulfur and petroleum resin, needs to be heated to 50-60℃ to soften, and can be reused after cooling, but repeated heating can easily lead to component decomposition (releasing VOCs), and mechanical cutting and correction are required after hardening, which is cumbersome to operate.

[0004] Environmental pollution: Synthetic resins (such as epoxy resins) and plasticizers (phthalates) in traditional sludge are difficult to biodegrade and remain in the environment for a long time after being discarded. Studies have shown that the degradation rate of industrial sludge in the natural environment is less than 20% within 180 days;

[0005] Safety and application limitations: Industrial sludge often contains heavy metal stabilizers such as lead and cadmium, which does not comply with GB 6675-2014 "Toy Safety Standard" and EU EN71-3 requirements, limiting its use in children's education.

[0006] Performance defects: The difference between the softening temperature and the hardening temperature of traditional temperature-sensitive sludge is large (for example, softening requires 40°C and hardening requires below 25°C), resulting in a narrow shaping window and poor environmental adaptability.

[0007] The present invention innovatively designs a temperature-sensitive modeling clay with precise and controllable temperature sensing performance, unlimited recycling and environmental protection, safety and applicability in multiple scenarios, and a balance between process cost and performance, so as to solve the above-mentioned technical problems, thereby necessitating the use of this temperature-sensitive modeling clay and its preparation method. Summary of the Invention

[0008] In view of the deficiencies in the prior art, the present invention provides a temperature-sensitive modeling clay and a preparation method thereof, which solves the technical problems raised in the above-mentioned background technology.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions: a temperature-sensitive modeling clay and a preparation method thereof, wherein the modeling clay is composed of the following raw materials in parts by weight:

[0010] A: 55-65 parts of beeswax; B: 15-20 parts of edible-grade wax oil; C: 8-12 parts of edible-grade vegetable oil; D: 50-75 parts of edible-grade starch; E: 1-3 parts of food coloring.

[0011] The molding clay preparation method is as follows:

[0012] S1. Raw material pretreatment: crush the block beeswax (melting point 62-65℃) into particles with a particle size of ≤2mm using a low-temperature crusher (working temperature ≤10℃) to prevent adhesion;

[0013] Food-grade starch (moisture ≤ 12%) was sieved through 50-100 mesh and dried in an oven at 60°C for 2 hours to control the final moisture content to ≤ 5%;

[0014] Wax oil (melting point 30-35°C) and vegetable oil (such as coconut oil, soybean oil) are pre-mixed in proportion, heated to 40°C and stirred for 10 minutes until a uniform liquid state is obtained;

[0015] S2. Calendering process: prepare a double-roll calender (roller temperature is set to 25-30°C, and the roller spacing is adjustable from 1 to 3 mm);

[0016] Put the crushed beeswax particles, dry starch and food coloring into the calender feed port in proportion;

[0017] The calender rolls 3-5 times to form a sheet substrate with a thickness of 1-3 mm;

[0018] The liquid mixed oil is evenly sprayed on the sheet surface through a high-pressure spray device (atomization pressure 0.3-0.5MPa) to form "oil-solid composite floccules";

[0019] After discharging, the material was allowed to stand for 30 minutes to allow the liquid component to penetrate into the solid.

[0020] S3, hot melt stirring process: prepare a sandwich stirring tank (with an anchor stirring paddle, a rotation speed of 30-50 rpm, and a heating medium of thermal oil);

[0021] Temperature: 80℃±2℃ (below the melting temperature of beeswax to avoid starch gelatinization);

[0022] Time: 1.5 hours ± 10 minutes, until the material becomes a homogeneous paste;

[0023] Vacuum degree: -0.05MPa (vacuum to remove bubbles);

[0024] S4, cooling and parking:

[0025] The first stage (initial cooling and setting):

[0026] Transfer the hot melt material to a stainless steel tray (thickness ≤ 5 cm) and place it in a constant temperature chamber at 25°C;

[0027] Let it stand for 12 hours to allow the material to cool naturally to room temperature (25-30°C) and the beeswax to initially crystallize and form a network skeleton;

[0028] Second stage (low temperature stabilization):

[0029] Transfer the material to a 5°C cold storage room and keep it for another 6 hours;

[0030] S5, screw mixing process:

[0031] Prepare a co-rotating twin-screw extruder (length-to-diameter ratio 40:1, 6 temperature control zones);

[0032] The 6 temperature control zones are 50℃, 55℃, 60℃, 60℃, 55℃ and 50℃ respectively;

[0033] Screw speed: 20-30rpm;

[0034] Feeding rate: 10kg / h (matched with the rotation speed to prevent blockage);

[0035] Mixing mechanism:

[0036] Through screw shear (shear rate 200-300s -1 ) Breaking up large beeswax crystals to evenly disperse the starch in the wax base;

[0037] The die hole diameter is 5mm, the strip material is extruded and cut into 10cm pieces 3 Block;

[0038] S6, extrusion molding and packaging:

[0039] Extrusion shaping: The mixed material is formed into strips with a diameter of 3-5mm or customized shapes through a plunger extruder (temperature 40℃);

[0040] Cutting accuracy: ±1mm (laser cutting machine);

[0041] Packaging: Foil bag filled with nitrogen and sealed (residual oxygen ≤ 1%), 100g ± 2g per bag;

[0042] The outer packaging is marked with the instructions for use: "Shape at hand temperature, restore at room temperature."

[0043] Preferably, the weight ratio of the beeswax to the wax oil is 3:1 to 4:1.

[0044] Preferably, in the calendering process, the solid raw material is crushed to a particle size of ≤2 mm, and calendered into sheets or flocs with a thickness of 1-3 mm, and the liquid raw material is evenly attached to the solid surface by spraying.

[0045] Preferably, the modeling clay has a hardness of Shore A 50-60 at room temperature, a softening temperature of 30-40° C., and recovers more than 95% of its initial hardness within 2 hours at room temperature.

[0046] Beneficial effects

[0047] The present invention provides a temperature-sensitive modeling clay and a preparation method thereof. The temperature-sensitive performance of the present invention can accurately control the hand temperature response: after the beeswax-wax oil system is modified, the softening temperature of the material is reduced to 30-40°C, which perfectly matches the human hand temperature (33-37°C), and no external heating tools are required for shaping.

[0048] Data support: DSC test shows that the melting peak is 35.2℃ and the crystallization peak is 28.5℃, indicating that the material can undergo reversible transformation in the range of 33-40℃.

[0049] Rapid recovery: After being placed at room temperature (25°C) for 2 hours, the hardness recovers to more than 98% of the initial value (Shore A50→49), which is much better than the 24-hour recovery period of traditional sludge.

[0050] Unlimited recycling and environmental protection Cycle life: After 100 kneading-setting tests (ASTM D412), the material tensile strength retention rate is greater than 95%, and there is no visible crack.

[0051] All ingredients are biodegradable: beeswax, vegetable oil and starch are all natural ingredients. The weight loss rate in the 180-day composting experiment is 82% (GB / T 19277.1 test), which is much higher than the 18% of industrial sludge.

[0052] Zero waste process: production waste and usage residues can be 100% recycled, and there is no performance degradation after screw mixing.

[0053] Safety and multi-scenario compatibility: Made from food-grade materials, it complies with GB 4806.1-2016 food contact material standards, with heavy metal migration levels (lead <0.01 mg / kg, cadmium undetectable) 50 times lower than the national standard limit. Child-friendly design: Hand-heated shaping reduces burn risks, and the material is non-toxic, odorless, and EN71-3:2019 certified.

[0054] Industrial-grade precision: The screw mixing process makes the material color difference ΔE≤1.5, which can meet the surface finish requirements of automotive clay models (Ra≤1.6μm).

[0055] Process cost and performance balance

[0056] Low-cost starch alternative: starch accounts for 50-75%, which is 60% lower than the cost of pure wax-based materials.

[0057] Energy consumption optimization: The whole processing temperature is ≤85℃, which saves 40% energy compared with traditional sludge (mixing temperature 120-150℃).

[0058] Improved uprightness: The starch-beeswax network structure improves the material's ability to resist collapse, and the upright height can reach 30cm (traditional oil clay ≤10cm). DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0060] The present invention provides a technical solution: a temperature-sensitive modeling clay and a preparation method thereof, wherein the modeling clay is composed of the following raw materials in parts by weight:

[0061] A: 55-65 parts of beeswax; B: 15-20 parts of edible-grade wax oil; C: 8-12 parts of edible-grade vegetable oil; D: 50-75 parts of edible-grade starch; E: 1-3 parts of food coloring.

[0062] The molding clay preparation method is as follows:

[0063] S1. Raw material pretreatment: crush the block beeswax (melting point 62-65℃) into particles with a particle size of ≤2mm using a low-temperature crusher (working temperature ≤10℃) to prevent adhesion;

[0064] Food-grade starch (moisture ≤ 12%) was sieved through 50-100 mesh and dried in an oven at 60°C for 2 hours to control the final moisture content to ≤ 5%;

[0065] Wax oil (melting point 30-35°C) and vegetable oil (such as coconut oil, soybean oil) are pre-mixed in proportion, heated to 40°C and stirred for 10 minutes until a uniform liquid state is obtained;

[0066] S2. Calendering process: prepare a double-roll calender (roller temperature is set to 25-30°C, and the roller spacing is adjustable from 1 to 3 mm);

[0067] Put the crushed beeswax particles, dry starch and food coloring into the calender feed port in proportion;

[0068] The calender rolls 3-5 times to form a sheet substrate with a thickness of 1-3 mm;

[0069] The liquid mixed oil is evenly sprayed on the sheet surface through a high-pressure spray device (atomization pressure 0.3-0.5MPa) to form "oil-solid composite floccules";

[0070] After discharging, the material was allowed to stand for 30 minutes to allow the liquid component to penetrate into the solid.

[0071] S3, hot melt stirring process: prepare a sandwich stirring tank (with an anchor stirring paddle, a rotation speed of 30-50 rpm, and a heating medium of thermal oil);

[0072] Temperature: 80℃±2℃ (below the melting temperature of beeswax to avoid starch gelatinization);

[0073] Time: 1.5 hours ± 10 minutes, until the material becomes a homogeneous paste;

[0074] Vacuum degree: -0.05MPa (vacuum to remove bubbles);

[0075] S4, cooling and parking:

[0076] The first stage (initial cooling and setting):

[0077] Transfer the hot melt material to a stainless steel tray (thickness ≤ 5 cm) and place it in a constant temperature chamber at 25°C;

[0078] Let it stand for 12 hours to allow the material to cool naturally to room temperature (25-30°C) and the beeswax to initially crystallize and form a network skeleton;

[0079] Second stage (low temperature stabilization):

[0080] Transfer the material to a 5°C cold storage room and keep it for another 6 hours;

[0081] S5, screw mixing process:

[0082] Prepare a co-rotating twin-screw extruder (length-to-diameter ratio 40:1, 6 temperature control zones);

[0083] The 6 temperature control zones are 50℃, 55℃, 60℃, 60℃, 55℃ and 50℃ respectively;

[0084] Screw speed: 20-30rpm;

[0085] Feeding rate: 10kg / h (matched with the rotation speed to prevent blockage);

[0086] Mixing mechanism:

[0087] Through screw shear (shear rate 200-300s -1 ) Breaking up large beeswax crystals to evenly disperse the starch in the wax base;

[0088] The die hole diameter is 5mm, the strip material is extruded and cut into 10cm pieces 3 Block;

[0089] S6, extrusion molding and packaging:

[0090] Extrusion shaping: The mixed material is formed into strips with a diameter of 3-5mm or customized shapes through a plunger extruder (temperature 40℃);

[0091] Cutting accuracy: ±1mm (laser cutting machine);

[0092] Packaging: Foil bag filled with nitrogen and sealed (residual oxygen ≤ 1%), 100g ± 2g per bag;

[0093] The outer packaging is marked with the instructions for use: "Shape at hand temperature, restore at room temperature."

[0094] This embodiment is further configured such that the weight ratio of the beeswax to the wax oil is 3:1 to 4:1.

[0095] This embodiment is further configured such that, in the calendering process, the solid raw material is crushed to a particle size of ≤2 mm, and calendered into sheets or flocs with a thickness of 1-3 mm, and the liquid raw material is evenly attached to the solid surface by spraying.

[0096] This embodiment is further configured such that the modeling clay has a room temperature hardness of Shore A 50-60, a softening temperature of 30-40° C., and recovers more than 95% of its initial hardness within 2 hours at room temperature.

[0097] The detailed connection means are well-known technologies in this field. The following mainly introduces the working principle and process. The specific operations are as follows.

[0098] Example: S1, raw material pretreatment: crush block beeswax (melting point 62-65°C) into particles with a particle size of ≤2mm, using a low-temperature crusher (working temperature ≤10°C) to prevent adhesion;

[0099] Food-grade starch (moisture ≤ 12%) was sieved through 50-100 mesh and dried in an oven at 60°C for 2 hours to control the final moisture content to ≤ 5%;

[0100] Wax oil (melting point 30-35°C) and vegetable oil (such as coconut oil, soybean oil) are pre-mixed in proportion, heated to 40°C and stirred for 10 minutes until a uniform liquid state is obtained;

[0101] S2. Calendering process: prepare a double-roll calender (roller temperature is set to 25-30°C, and the roller spacing is adjustable from 1 to 3 mm);

[0102] Put the crushed beeswax particles, dry starch and food coloring into the calender feed port in proportion;

[0103] The calender rolls 3-5 times to form a sheet substrate with a thickness of 1-3 mm;

[0104] The liquid mixed oil is evenly sprayed on the sheet surface through a high-pressure spray device (atomization pressure 0.3-0.5MPa) to form "oil-solid composite floccules";

[0105] After discharging, the material was allowed to stand for 30 minutes to allow the liquid component to penetrate into the solid.

[0106] S3, hot melt stirring process: prepare a sandwich stirring tank (with an anchor stirring paddle, a rotation speed of 30-50 rpm, and a heating medium of thermal oil);

[0107] Temperature: 80℃±2℃ (below the melting temperature of beeswax to avoid starch gelatinization);

[0108] Time: 1.5 hours ± 10 minutes, until the material becomes a homogeneous paste;

[0109] Vacuum degree: -0.05MPa (vacuum to remove bubbles);

[0110] S4, cooling and parking:

[0111] The first stage (initial cooling and setting):

[0112] Transfer the hot melt material to a stainless steel tray (thickness ≤ 5 cm) and place it in a constant temperature chamber at 25°C;

[0113] Let it stand for 12 hours to allow the material to cool naturally to room temperature (25-30°C) and the beeswax to initially crystallize and form a network skeleton;

[0114] Second stage (low temperature stabilization):

[0115] Transfer the material to a 5°C cold storage room and keep it for another 6 hours;

[0116] S5, screw mixing process:

[0117] Prepare a co-rotating twin-screw extruder (length-to-diameter ratio 40:1, 6 temperature control zones);

[0118] The 6 temperature control zones are 50℃, 55℃, 60℃, 60℃, 55℃ and 50℃ respectively;

[0119] Screw speed: 20-30rpm;

[0120] Feeding rate: 10kg / h (matched with the rotation speed to prevent blockage);

[0121] Mixing mechanism:

[0122] Through screw shear (shear rate 200-300s -1 ) Breaking up large beeswax crystals to evenly disperse the starch in the wax base;

[0123] The die hole diameter is 5mm, the strip material is extruded and cut into 10cm pieces 3 Block;

[0124] S6, extrusion molding and packaging:

[0125] Extrusion shaping: The mixed material is formed into strips with a diameter of 3-5mm or customized shapes through a plunger extruder (temperature 40℃);

[0126] Cutting accuracy: ±1mm (laser cutting machine);

[0127] Packaging: Foil bag filled with nitrogen and sealed (residual oxygen ≤ 1%), 100g ± 2g per bag;

[0128] The outer packaging is marked with the instructions for use: "Shape at hand temperature, restore at room temperature."

[0129] Example 1: 60 parts of beeswax, 18 parts of cosmetic grade wax oil, 10 parts of coconut oil, 65 parts of potato starch, and 2 parts of food coloring;

[0130] The mixture was rolled into 2 mm sheets, melt-stirred at 85 °C for 1.5 h, twin-screw compounded (25 rpm, 60 °C), and cooled in stages.

[0131] The hardness of the finished product is Shore A 55, the softening time at 35℃ is 2.5 minutes, and the hardness recovers to 98% at room temperature in 2 hours.

[0132] Example 2: 58 parts of beeswax, 16 parts of edible wax oil, 9 parts of soybean oil, 70 parts of corn starch, and 1.5 parts of pigment;

[0133] The process is the same as that of Example 1. The hardness of the finished product is Shore A 58, which is suitable for industrial mold reproduction.

[0134] Experimental data:

[0135] Temperature response test (DSC analysis): melting peak temperature 35.2℃, crystallization peak temperature 28.5℃;

[0136] Mechanical properties (ASTM D638): tensile strength 0.8 MPa, elongation at break 220%;

[0137] Environmental protection: The weight loss rate in soil burial test was 15% after 28 days and 82% after 180 days.

[0138] It should be noted that, in this document, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

Claims

1. A temperature-sensitive modeling clay and a preparation method thereof, characterized in that: The modeling clay is composed of the following raw materials in parts by weight: A: 55-65 parts of beeswax; B: 15-20 parts of edible-grade wax oil; C: 8-12 parts of edible-grade vegetable oil; D: 50-75 parts of edible-grade starch; E: 1-3 parts of food coloring. The molding clay preparation method is as follows: S1. Raw material pretreatment: crush the block beeswax into particles with a particle size of ≤2mm. The melting point of the beeswax is 62-65°C. Use a low-temperature crusher to prevent adhesion. Food-grade starch was sieved through 50-100 mesh and dried in an oven at 60°C for 2 hours to control the final moisture content to ≤5%; Wax oil and vegetable oil are pre-mixed in proportion, wherein the wax oil has a melting point of 30-35°C, and heated to 40°C and stirred for 10 minutes until it becomes a uniform liquid; S2, calendering process: prepare a double-roll calender, set the roller temperature of the double-roll calender to 25-30°C, and the roller spacing is adjustable from 1 to 3 mm; Put the crushed beeswax particles, dry starch and food coloring into the calender feed port in proportion; The calender rolls 3-5 times to form a sheet substrate with a thickness of 1-3 mm; The liquid mixed oil is evenly sprayed on the sheet surface through a high-pressure spray device with an atomization pressure of 0.3-0.5 MPa to form "oil-solid composite floccules"; After discharging, the material was allowed to stand for 30 minutes to allow the liquid component to penetrate into the solid. S3, hot melt stirring process: prepare a sandwich stirring tank with an anchor-type stirring paddle, a rotation speed of 30-50 rpm, and the heating medium is thermal oil; Temperature: 80℃±2℃; Time: 1.5 hours ± 10 minutes, until the material becomes a homogeneous paste; Vacuum degree: -0.05MPa; S4, cooling and parking: The first stage of initial cooling and setting: Transfer the hot melt material to a stainless steel tray with a thickness of ≤5 cm and place it in a constant temperature room at 25°C; Let it stand for 12 hours to allow the material to cool naturally to room temperature (25-30°C) and the beeswax to initially crystallize and form a network skeleton; Second stage low temperature stabilization: Transfer the material to a 5°C cold storage room and keep it for another 6 hours; S5, screw mixing process: Prepare a co-rotating twin-screw extruder with a length-to-diameter ratio of 40:1 and 6 temperature-controlled zones); The 6 temperature control zones are 50℃, 55℃, 60℃, 60℃, 55℃ and 50℃ respectively; Screw speed: 20-30rpm; Feeding rate: 10kg / h; Mixing mechanism: The large crystals of beeswax are broken by screw shearing at a shear rate of 200-300s-1, so that the starch is evenly dispersed in the wax base; The die hole diameter is 5mm, the strip material is extruded and cut into 10cm pieces 3 Block; S6, extrusion molding and packaging: Extrusion shaping: The mixed material is formed into strips with a diameter of 3-5mm or customized shapes through a plunger extruder; Cutting accuracy: ±1mm; Packaging: Foil bag filled with nitrogen and sealed, 100g±2g per bag; The outer packaging is marked with the instructions for use: "Shape at hand temperature, restore at room temperature." 2. The temperature-sensitive modeling clay and preparation method thereof according to claim 1, characterized in that: The weight ratio of the beeswax to the wax oil is 3:1 to 4:

1.

3. The temperature-sensitive modeling clay and preparation method thereof according to claim 1, characterized in that: In the calendering process, the solid raw material is crushed to a particle size of ≤2 mm, and calendered into a sheet or flocculent material with a thickness of 1-3 mm, and the liquid raw material is evenly attached to the solid surface by spraying.

4. The temperature-sensitive modeling clay and the preparation method thereof according to claim 1, characterized in that: The modeling clay has a hardness of Shore A 50-60 at room temperature and a softening temperature of 30-40° C., and recovers more than 95% of its initial hardness within 2 hours when placed at room temperature.