Phase change energy storage decorative plate material and preparation process thereof

Abstract

The invention provides a phase-change energy-storage decorative plate material and a preparation method thereof, and belongs to the technical field of phase-change composites.The phase-change energy-storage decorative plate material is prepared from, by weight, 90 parts of gypsum powder, 5-6 parts of acid-treated vermiculite, 4-5 parts of modified glass fibers, 30 parts of a phase-change material, 56-60 parts of deionized water, 1-1.3 parts of a water reducing agent and 0.3-0.5 part of a retarder; the phase change material is prepared from capric acid, palmitic acid and diatomite according to the mass ratio of (85-87): (14-16): (67-69). The high doping amount of the phase-change material is ensured, so that the service life of the phase-change energy-storage decorative plate material is prolonged while the prepared phase-change energy-storage decorative plate material has a high latent heat value.

Description

Technical Field

[0001] The present invention belongs to the technical field of phase change composite materials, and in particular relates to a phase change energy storage decorative plate material and a preparation process thereof. Background Art

[0002] Phase change materials maintain a constant temperature during their solidification (liquid to solid) and melting (solid to liquid) processes, while simultaneously absorbing or releasing large amounts of latent heat, thereby achieving efficient energy storage and release. Existing phase change materials are made from capric acid, palmitic acid, and diatomaceous earth, with a capric-palmitic acid mass fraction of approximately 60%. This phase change material is applied to a building gypsum matrix to prepare a phase change energy storage gypsum composite material, namely a phase change energy storage decorative panel material. The amorphous phase change material is used as a fixing material in the decorative panel material, enhancing the panel material's temperature regulation performance.

[0003] Research has shown that when the mass (dosage) of this phase-change material is 25% of the mass of gypsum, the latent heat is 8.5 J / g, the 7-day absolute dry compressive strength is 6.5 MPa, the 7-day saturated compressive strength is 5.5 MPa, and the water absorption rate is 15%. To increase the latent heat of phase change in decorative board materials, the dosage of the phase-change material can be increased. For example, when the dosage of the phase-change material is increased to 30% of the mass of gypsum, the latent heat value can be increased to over 10 J / g.

[0004] However, at the same time, the compressive strength of the decoration board material will decrease, and the water absorption rate will increase, resulting in a decrease in the service life of the decoration board. Summary of the Invention

[0005] In order to solve the problems existing in the background technology, the present invention provides a phase change energy storage decorative panel material and its preparation process, ensuring a high dosage of phase change material to ensure that the phase change energy storage decorative panel material has a high latent heat value while improving the service life of the phase change energy storage decorative panel material (increased compressive strength and reduced water absorption rate).

[0006] In order to achieve the above-mentioned objectives, in a first aspect, the present invention provides a phase change energy storage decorative board material, which comprises the following components, in parts by weight: 90 parts of gypsum powder, 5-6 parts of acid-treated vermiculite, 4-5 parts of modified glass fiber, 30 parts of phase change material, 56-60 parts of deionized water, 1-1.3 parts of water reducer and 0.3-0.5 parts of retarder; the phase change material is prepared from capric acid, palmitic acid and diatomaceous earth in a mass ratio of (85-87): (14-16): (67-69).

[0007] Furthermore, the preparation method of the acid-treated vermiculite is as follows:

[0008] A1. Grind 5-6 g of vermiculite to obtain vermiculite powder;

[0009] A2. Add 180-200 mL of 1.5 mol / L hydrochloric acid solution to the vermiculite powder obtained in A1, stir, heat to 80-85° C., and keep warm for 2-3 hours to obtain a mixed solution;

[0010] A3. Filter the mixed solution obtained in A2 to obtain a solid, rinse it, and dry it to obtain acid-treated vermiculite.

[0011] Furthermore, the particle size of the vermiculite powder is less than 150 μm.

[0012] Further, in A3, the filtrate is rinsed until the pH value is 6-7.

[0013] Furthermore, in A3, the drying temperature is 60-70° C., and the drying time is 80-90 min.

[0014] Furthermore, the preparation method of the modified fiber is as follows:

[0015] B1. Gelatinize 10 g of cationic starch at 85-90° C., then add 170-180 g of deionized water, stir, and cool to room temperature to obtain a first treated liquid;

[0016] B2, dissolving 0.7 g of sodium carboxymethyl cellulose in 130-135 g of deionized water to obtain a second treatment solution;

[0017] B3. Take 10g of glass fiber and soak it in the first treatment solution obtained in B1 for 11-13 minutes, filter it out, then transfer it to the second treatment solution obtained in B2 and soak it for 5-6 minutes, filter it out, and air-dry to obtain modified glass fiber.

[0018] Furthermore, in B1, the gelatinization time is 30-35 min.

[0019] In a second aspect, the present invention provides a method for preparing the above-mentioned phase change energy storage decorative plate material, comprising the following steps:

[0020] S1, stirring and mixing gypsum powder, phase change material, acid-treated vermiculite and modified glass fiber to obtain a first mixture;

[0021] S2, stirring and mixing deionized water, a water reducer and a retarder to obtain a second mixture;

[0022] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in batches, stir and mix, inject into the mold, vibrate to expel bubbles, scrape the surface flat, let it stand for 47-50 hours in an environment with a temperature of 20±2°C and a humidity of 60-70%, demold, and dry at 40±2°C to constant weight to obtain the phase change energy storage decorative board material.

[0023] This application has the following beneficial effects:

[0024] 1. In the preparation of the phase-change energy storage decorative board material of the present invention, acid-treated vermiculite and modified glass fiber are added to the basic raw materials gypsum powder and phase-change material. The modified glass fiber can be embedded in the porous layered structure of the acid-treated vermiculite to form a three-dimensional network support skeleton, blocking the crack propagation path, thereby synergistically improving the compressive strength; the modified glass fiber and the acid-treated vermiculite form a composite interlaced structure, converting open pores into isolated closed pores, reducing the pore connectivity, weakening the capillary water absorption effect, and thereby synergistically reducing the water absorption rate.

[0025] 2. In the preparation of modified glass fiber, the glass fiber is treated with cationic starch and sodium carboxymethyl cellulose. Cationic starch contains quaternary ammonium groups, which are grafted onto the surface of the glass fiber to make it positively charged (-N + (CH3)3), enhance the negatively charged gypsum particles (gypsum particles in neutral / alkaline environment due to SO4 2- Dissociation and Ca 2+ Loss and stable negative charge) electrostatic attraction; at the same time, the carboxyl group (-COO - ) is adsorbed on the surface of glass fiber through hydrogen bonding, and its free carboxyl groups react with Ca in gypsum hydration products. 2+ Formation of "Ca 2+ -COO - Ionic bond” to achieve fiber-matrix chemical bonding, thereby improving compressive strength.

[0026] 3. In the preparation of modified glass fiber, the carboxyl group (-COO - ) can react with the residual H in acid-treated vermiculite + reaction, reducing the acidity of the system and reducing / offsetting the inhibition of gypsum hydration reaction; sodium carboxymethyl cellulose forms a hydrophobic layer on the surface of the glass fiber, and its hydrophobic groups (such as -CH3) are directionally arranged on the surface of the glass fiber to form a dense molecular layer, which reduces the surface energy, increases the contact angle, and blocks the penetration of liquid water; at the same time, the hydrophobic layer of the modified glass fiber can also cover the surface of vermiculite / diatomaceous earth, reducing the capillary effect of the pores, and cationic starch and sodium carboxymethyl cellulose form an interpenetrating network, filling the microscopic pores of vermiculite / diatomaceous earth, blocking the penetration path of water molecules, thereby reducing the water absorption rate. DETAILED DESCRIPTION

[0027] The present application is further described in detail below with reference to the embodiments.

[0028] Unless otherwise specified, the raw materials used in the examples and comparative examples of the present application are all commercially available.

[0029] Example 1: (1) Preparation of acid-treated vermiculite, the preparation method thereof is as follows:

[0030] A1. Grind 55 g of vermiculite to a particle size of less than 150 μm to obtain vermiculite powder.

[0031] A2. Add 1900 mL of 1.5 mol / L hydrochloric acid solution to the vermiculite powder obtained in A1, stir, heat to 82° C., and keep warm for 2.5 h to obtain a mixed solution.

[0032] A3. Filter the mixed solution obtained in A2 to obtain a solid, rinse with water until the filtrate has a pH of about 6.5, and dry at 65° C. for 85 minutes to obtain acid-treated vermiculite.

[0033] (2) Prepare modified fiber, the preparation method is as follows:

[0034] B1. Gelatinize 100 g of cationic starch at 87° C. for 32 min, then add 1750 g of deionized water, stir, and cool to room temperature to obtain a first treated liquid.

[0035] B2. Dissolve 7 g of sodium carboxymethyl cellulose in 1320 g of deionized water to obtain a second treatment solution.

[0036] B3. Take 100g of glass fiber and soak it in the first treatment solution obtained in B1 for 12 minutes, filter it out, transfer it to the second treatment solution obtained in B2 and soak it for 6 minutes, filter it out, and air-dry to obtain modified glass fiber.

[0037] (3) Prepare phase change material, the preparation method is as follows:

[0038] Capric acid, palmitic acid, and diatomaceous earth were weighed in a mass ratio of 86:15:68. The capric acid and palmitic acid were first melt-mixed in an 80°C water bath for 4 hours to form a eutectic, which was then cooled to room temperature for later use. The diatomaceous earth was then dried at 105°C for 24 hours. The eutectic and diatomaceous earth were then ultrasonically mixed at 80°C for 15 minutes and then melt-mixed at 80°C for 4 hours to obtain a phase change material.

[0039] (4) Prepare phase change energy storage decorative board material, the preparation method is as follows:

[0040] S1. By weight, 90 parts of gypsum powder, 5.5 parts of acid-treated vermiculite, 4.5 parts of modified glass fiber and 30 parts of phase change material were stirred and mixed to obtain a first mixture.

[0041] S2. 58 parts of deionized water, 1.2 parts of water reducer, and 0.4 parts of retarder were stirred and mixed by equal weight to obtain a second mixture. The water reducer was a naphthalene-based water reducer purchased from Shandong Hongquan Chemical Technology Co., Ltd. The gypsum retarder was a polyphosphate-based gypsum retarder purchased from Jingzhou Yinjie Chemical Co., Ltd.

[0042] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in three times, stir and mix, inject into the mold, vibrate for 30 seconds to expel bubbles, scrape the surface flat, let it stand for 48 hours in an environment with a temperature of 20°C and a humidity of about 65%, demould, and dry at 40°C to constant weight to obtain the phase change energy storage decorative board material.

[0043] Example 2: The difference between this example and Example 1 is that a phase change energy storage decorative plate material is prepared, and the preparation method is as follows:

[0044] S1. By weight, 90 parts of gypsum powder, 5 parts of acid-treated vermiculite, 5 parts of modified glass fiber and 30 parts of phase change material are stirred and mixed to obtain a first mixture.

[0045] S2. Calculated by the same weight parts, 56 parts of deionized water, 1 part of water reducer and 0.3 part of retarder were stirred and mixed to obtain a second mixture.

[0046] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in three times, stir and mix, inject into the mold, vibrate for 30 seconds to expel bubbles, scrape the surface flat, let it stand for 48 hours in an environment with a temperature of 20°C and a humidity of about 65%, demould, and dry at 40°C to constant weight to obtain the phase change energy storage decorative board material.

[0047] Example 3: The difference between this example and Example 1 is that a phase change energy storage decorative plate material is prepared, and the preparation method is as follows:

[0048] S1. By weight, 90 parts of gypsum powder, 6 parts of acid-treated vermiculite, 4 parts of modified glass fiber and 30 parts of phase change material are stirred and mixed to obtain a first mixture.

[0049] S2. Calculated by the same weight parts, 60 parts of deionized water, 1.3 parts of water reducer and 0.5 parts of retarder were stirred and mixed to obtain a second mixture.

[0050] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in three times, stir and mix, inject into the mold, vibrate for 30 seconds to expel bubbles, scrape the surface flat, let it stand for 48 hours in an environment with a temperature of 20°C and a humidity of about 65%, demould, and dry at 40°C to constant weight to obtain the phase change energy storage decorative board material.

[0051] Comparative Example 1: The difference between this comparative example and Example 1 is that in the preparation of the phase change energy storage decorative board material, the acid-treated vermiculite and modified glass fiber are replaced by gypsum powder.

[0052] The details are as follows: a phase change energy storage decorative board material is prepared, and the preparation method is as follows:

[0053] S1. By weight, 100 parts of gypsum powder and 30 parts of phase change material are stirred and mixed to obtain a first mixture.

[0054] S2. 58 parts of deionized water, 1.2 parts of water reducer, and 0.4 parts of retarder were stirred and mixed by equal weight to obtain a second mixture. The water reducer was a naphthalene-based water reducer purchased from Shandong Hongquan Chemical Technology Co., Ltd. The gypsum retarder was a polyphosphate-based gypsum retarder purchased from Jingzhou Yinjie Chemical Co., Ltd.

[0055] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in three times, stir and mix, inject into the mold, vibrate for 30 seconds to expel bubbles, scrape the surface flat, let it stand for 48 hours in an environment with a temperature of 20°C and a humidity of about 65%, demould, and dry at 40°C to constant weight to obtain the phase change energy storage decorative board material.

[0056] Comparative Example 2: The difference between this comparative example and Example 1 is that in the preparation of the phase change energy storage decorative board material, the modified glass fiber is replaced by gypsum powder.

[0057] The details are as follows: a phase change energy storage decorative board material is prepared, and the preparation method is as follows:

[0058] S1. By weight, 94.5 parts of gypsum powder, 5.5 parts of acid-treated vermiculite and 30 parts of phase change material were stirred and mixed to obtain a first mixture.

[0059] S2. 58 parts of deionized water, 1.2 parts of water reducer, and 0.4 parts of retarder were stirred and mixed by equal weight to obtain a second mixture. The water reducer was a naphthalene-based water reducer purchased from Shandong Hongquan Chemical Technology Co., Ltd. The gypsum retarder was a polyphosphate-based gypsum retarder purchased from Jingzhou Yinjie Chemical Co., Ltd.

[0060] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in three times, stir and mix, inject into the mold, vibrate for 30 seconds to expel bubbles, scrape the surface flat, let it stand for 48 hours in an environment with a temperature of 20°C and a humidity of about 65%, demould, and dry at 40°C to constant weight to obtain the phase change energy storage decorative board material.

[0061] Comparative Example 3: The difference between this comparative example and Example 1 is that in the preparation of the phase change energy storage decorative board material, the acid-treated vermiculite is replaced by gypsum powder.

[0062] The details are as follows: a phase change energy storage decorative board material is prepared, and the preparation method is as follows:

[0063] S1. By weight, 95.5 parts of gypsum powder, 4.5 parts of modified glass fiber and 30 parts of phase change material were stirred and mixed to obtain a first mixture.

[0064] S2. 58 parts of deionized water, 1.2 parts of water reducer, and 0.4 parts of retarder were stirred and mixed by equal weight to obtain a second mixture. The water reducer was a naphthalene-based water reducer purchased from Shandong Hongquan Chemical Technology Co., Ltd. The gypsum retarder was a polyphosphate-based gypsum retarder purchased from Jingzhou Yinjie Chemical Co., Ltd.

[0065] S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in three times, stir and mix, inject into the mold, vibrate for 30 seconds to expel bubbles, scrape the surface flat, let it stand for 48 hours in an environment with a temperature of 20°C and a humidity of about 65%, demould, and dry at 40°C to constant weight to obtain the phase change energy storage decorative board material.

[0066] Test example: Test object: Phase change energy storage decorative board materials were prepared according to Example 1-Example 3 and Comparative Example 1-Comparative Example 3.

[0067] Test Items and Methods: ① Phase Change Enthalpy: Latent Heat (J / g). ② Compressive Strength (MPa): 7-day absolute dry compressive strength was measured in accordance with GBT 17669.3-1999, "Standard for Determination of Mechanical Properties of Building Gypsum." ③ Water Absorption (%): After 7 days of natural curing, each test object was oven-dried to a constant mass (m1). The gypsum block was then placed in a clean container filled with distilled water, completely submerged. After 24 hours, the surface moisture of the test block was wiped off with a saturated wet towel. The mass of the test block (m2) was immediately weighed and the water absorption calculated. Calculation formula: Water Absorption = (m2 - m1) / m1 × 100%.

[0068] Test results: See Table 1.

[0069] Table 1. Test results statistics

[0070] Latent heat value (J / g) Compressive strength (MPa) Water absorption (%) Example 1 10.6 7.7 15.0 Example 2 10.4 7.5 14.8 Example 3 10.4 7.8 15.0 Comparative Example 1 10.3 5.7 16.1 Comparative Example 2 10.2 5.2 16.9 Comparative Example 3 10.5 7.3 15.5

[0071] Result analysis: By analyzing Examples 1 to 3 and combining them with the data in Table 1, it can be seen that the latent heat value of the phase change energy storage decorative panel material prepared by the present invention (Examples 1 to 3) reaches more than 10.4 J / g, the compressive strength reaches more than 7.5 MPa, and the water absorption rate is as low as less than 15.0%.

[0072] By analyzing Example 1 and Comparative Examples 1 to 3 and combining them with the data in Table 1, and specifically comparing Comparative Example 1 with Comparative Example 2, it can be seen that compared with Comparative Example 1, the compressive strength of the phase change energy storage decorative board material obtained by introducing acid-treated vermiculite alone in Comparative Example 2 is reduced, and the water absorption rate is increased.

[0073] This is because, when acid-treated vermiculite is introduced alone, its porous layered structure will, on the one hand, destroy the continuity of the gypsum matrix, forming stress concentration points and making cracks more likely to expand. Furthermore, acidic residues (such as H+) react with Ca2+ in the gypsum to form a passivation layer that covers the surface of unhydrated gypsum particles and inhibits their further hydration. Insufficient hydration of the gypsum will lead to a reduction in hydration products (such as calcium aluminate), weakening the matrix skeleton strength, which in turn leads to a decrease in compressive strength. On the other hand, the interlayer pores of the vermiculite will interact with diatomaceous earth to form a connected capillary network, accelerating water penetration. The unreacted hydroxyl groups (-OH) on the vermiculite surface adsorb water molecules through hydrogen bonds. The H+ residues will also promote the dissolution of calcium ions in the gypsum, increasing the porosity, which in turn leads to an increase in water absorption.

[0074] Specifically, by comparing Comparative Example 1 and Comparative Example 3, it can be seen that compared with Comparative Example 1, the modified glass fiber is introduced alone in Comparative Example 3, and the compressive strength of the phase change energy storage decorative board material is significantly improved, and the water absorption rate is reduced.

[0075] By comparison with Example 1, it can be seen that on the basis of introducing modified glass fiber, acid-treated vermiculite is also introduced. The two can produce a synergistic effect, synergistically improve the compressive strength of the phase change energy storage decorative board material, and synergistically reduce its water absorption rate.

[0076] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0077] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A phase change energy storage decorative board material, characterized in that: The invention comprises the following components in parts by weight: 90 parts of gypsum powder, 5-6 parts of acid-treated vermiculite, 4-5 parts of modified glass fiber, 30 parts of phase change material, 56-60 parts of deionized water, 1-1.3 parts of water reducer and 0.3-0.5 parts of retarder; the phase change material is prepared from capric acid, palmitic acid and diatomaceous earth in a mass ratio of (85-87): (14-16): (67-69).

2. The phase change energy storage decorative plate material according to claim 1, characterized in that: The preparation method of the acid-treated vermiculite is as follows: A1. Grind 5-6 g of vermiculite to obtain vermiculite powder; A2. Add 180-200 mL of 1.5 mol / L hydrochloric acid solution to the vermiculite powder obtained in A1, stir, heat to 80-85° C., and keep warm for 2-3 hours to obtain a mixed solution; A3. Filter the mixed solution obtained in A2 to obtain a solid, rinse it, and dry it to obtain acid-treated vermiculite.

3. The phase change energy storage decorative plate material according to claim 2, characterized in that: The particle size of the vermiculite powder is less than 150 μm.

4. The phase change energy storage decorative plate material according to claim 2, characterized in that: A3, rinse until the filtrate pH = 6-7.

5. The phase change energy storage decorative plate material according to claim 2, characterized in that: In A3, the drying temperature is 60-70°C and the drying time is 80-90 minutes.

6. The phase change energy storage decorative plate material according to claim 1, characterized in that: The preparation method of the modified fiber is as follows: B1. Gelatinize 10 g of cationic starch at 85-90° C., then add 170-180 g of deionized water, stir, and cool to room temperature to obtain a first treated liquid; B2, dissolving 0.7 g of sodium carboxymethyl cellulose in 130-135 g of deionized water to obtain a second treatment solution; B3. Take 10g of glass fiber and soak it in the first treatment solution obtained in B1 for 11-13 minutes, filter it out, then transfer it to the second treatment solution obtained in B2 and soak it for 5-6 minutes, filter it out, and air-dry to obtain modified glass fiber.

7. The phase change energy storage decorative plate material according to claim 6, characterized in that: In B1, the gelatinization time was 30-35 min.

8. A method for preparing the phase change energy storage decorative plate material according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, stirring and mixing gypsum powder, phase change material, acid-treated vermiculite and modified glass fiber to obtain a first mixture; S2, stirring and mixing deionized water, a water reducer and a retarder to obtain a second mixture; S3. Add the second mixture obtained by S2 to the first mixture obtained by S1 in batches, stir and mix, inject into the mold, vibrate to expel bubbles, scrape the surface flat, let it stand for 47-50 hours in an environment with a temperature of 20±2°C and a humidity of 60-70%, demold, and dry at 40±2°C to constant weight to obtain the phase change energy storage decorative board material.