Preparation method and application of unsaturated resin for artificial stone

Abstract

A preparation method and application of an unsaturated resin for artificial stone, belonging to the technical field of unsaturated resins for construction. The method comprises the following steps: 1) Saturated polyester is synthesized by reacting saturated dibasic acid, diol, antioxidant and inhibitor under nitrogen protection with temperature rising; 2) Unsaturated polyester is synthesized by reacting the saturated polyester obtained in step 1), saturated dibasic acid, unsaturated dibasic acid, diol, antioxidant, inhibitor and paraffin under nitrogen protection; 3) Diluent, inhibitor and saturated polyester are added to the unsaturated polyester obtained in step 2), and the temperature is lowered and stirred to obtain the unsaturated resin for artificial stone; in step 1), the saturated dibasic acid is a 4, 5, 6-carbon dicarboxylic acid, which is composed of 12-23% by mass of adipic acid, 53-63% of glutaric acid and 17-25% of succinic acid. The unsaturated resin prepared by the preparation method of the present invention has the characteristics of high toughness, small shrinkage and excellent curing effect, and can be used as a binder for artificial stone for construction.

Description

Technical Field

[0001] A preparation method and application of unsaturated resin for artificial stone, belonging to the technical field of unsaturated resin for construction. Background Art

[0002] Artificial stone is formed and cured by using unsaturated polyester resin as a binder, powder filler, and appropriate coupling agent, flame retardant, and color through the methods of batching and mixing, vibration compression, and high-temperature curing. According to different use scenarios and processes, the resin content in general artificial marble is 22%-27% by mass percentage, and the resin content in artificial quartz stone is 7%-13% by mass percentage. The resin has a great influence on the performance and quality of artificial stone. During the process of resin curing transformation, due to the increase in density and volume shrinkage, huge internal stress is generated in the resin, resulting in problems such as cracking, warping deformation, and uneven surface of the plate always existing. And in order to pursue production speed, manufacturers hope that the resin cures quickly. However, the faster the resin cures, the greater the rigidity of the product. The greater the rigidity, the greater the brittleness, and the worse the toughness, seriously affecting the product quality and use effect of the product.

[0003] Patent CN202211402468.4, an unsaturated polyester resin for artificial quartz stone and its preparation method, improves the heat resistance, water resistance, and stain resistance of the resin, but does not meet the performance requirements of resin toughness and shrinkage rate; Patent CN202310107565.9, a granite-type unsaturated polyester resin and its preparation method, improves the fluidity of the resin, and also does not meet the performance requirements of resin toughness and shrinkage rate. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art and provide a preparation method and application of unsaturated resin for artificial stone, which has high toughness, small shrinkage, and excellent curing effect, and is suitable for use as a binder for artificial stone in construction.

[0005] The technical solution adopted by the present invention to solve its technical problems is: the preparation method of the unsaturated resin for artificial stone includes the following steps:

[0006] 1) Saturated polyester synthesis stage: Saturated dibasic acid, diol, antioxidant, and inhibitor are used to react and synthesize saturated polyester under nitrogen protection by heating.

[0007] 2) Unsaturated polyester synthesis stage: The saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol, antioxidant, inhibitor, and paraffin in step 1) are used to react and synthesize unsaturated polyester under nitrogen protection.

[0008] 3) Dilution stage: Add a diluent, a polymerization inhibitor, and a saturated polyester to the unsaturated polyester obtained in step 2), cool down and stir to obtain an unsaturated resin;

[0009] The saturated dibasic acid in step 1) is a 4, 5, 6-carbon dibasic acid, and the 4, 5, 6-carbon dibasic acid is a mixture composed of 12 - 23% by mass of adipic acid, 53 - 63% of glutaric acid, and 17 - 25% of succinic acid.

[0010] The specific operation of step 1) is as follows: Add the saturated dibasic acid, diol, antioxidant, and polymerization inhibitor to a reaction kettle, introduce nitrogen, start stirring, gradually heat up to 166 - 170 °C, keep warm for 20 - 40 minutes, then heat up to 202 - 208 °C at a rate of 15 - 25 °C / h, keep warm for reaction until the acid value drops to 16 - 20 mgKOH / g and the viscosity value is 2.6 - 3 Pa·s, then cool down to obtain a saturated polyester.

[0011] The specific operation of step 2) is as follows: Put the saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol, and antioxidant obtained in step 1) into a reaction kettle, introduce nitrogen, start stirring, gradually heat up to 167 - 173 °C, keep warm for 20 - 40 minutes, then heat up to 202 - 208 °C at a rate of 15 - 25 °C / h, keep warm for reaction until the acid value drops to 24 - 32 mgKOH / g and the viscosity value is 0.38 - 0.42 Pa·s, start to cool down. When it cools down to 177 - 183 °C, add a polymerization inhibitor and paraffin, continue to cool down. When it cools down to 122 - 128 °C, obtain an unsaturated polyester.

[0012] The specific operation of step 3) is as follows: When the temperature of the unsaturated polyester obtained in step 2) is 122 - 128 °C, add a diluent and a polymerization inhibitor, then add the saturated polyester in step 1), cool down and stir for 20 - 40 minutes to obtain an unsaturated resin.

[0013] The diol in step 1) is ethylene glycol, and the antioxidant in step 1) is triphenyl phosphite.

[0014] The saturated dibasic acid in step 2) is phthalic anhydride, the unsaturated dibasic acid in step 2) is maleic anhydride, the diol in step 2) is diethylene glycol, and the antioxidant in step 2) is triphenyl phosphite.

[0015] The diluent in step 3) is styrene, or a mixture of styrene and α-methylstyrene mixed in a mass ratio of 9.5 - 11:1. Preferably, the diluent in step 3) is a mixture of styrene and α-methylstyrene mixed in a mass ratio of 10.3 - 10.4:1. The reaction activity of α-methylstyrene is low, and a small amount of use can reduce the curing exothermic temperature, reduce the shrinkage rate, increase the flexibility, and 10.3 - 10.4:1 is the optimal ratio.

[0016] The addition amount of the saturated polyester described in step 3) accounts for 2%-4% by mass of the total feed amount of step 2) and step 3). The total feed amount of step 2) and step 3) refers to the sum of the weight parts of the raw material feed amount in step 2) and the raw material feed amount in step 3). Adding saturated polyester in the dilution stage of step 3) can make up for the curing shrinkage of the resin, reduce the resin shrinkage rate, and thus improve the quality problems of warping, deformation, and uneven surface of artificial stone products. The amount of saturated resin in step 3) should not be too much. If it exceeds 4% of the total feed amount of unsaturated resin, it will have an adverse effect on the final curing effect of the resin and reduce the product quality; if it is less than 2% of the total amount of unsaturated resin, it cannot play the role of reducing the shrinkage rate. Preferably, the saturated polyester described in step 3) is the saturated polyester synthesized by the reaction in step 1).

[0017] The polymerization inhibitor described in step 1), step 2), and step 3) is at least one of hydroquinone, p-tert-butylcatechol, and methylhydroquinone.

[0018] Preferably, the polymerization inhibitor described in step 1) is a mixture of hydroquinone and methylhydroquinone in a mass ratio of 1.8-2.2:1. Further preferably, the polymerization inhibitor described in step 1) is a mixture of hydroquinone and methylhydroquinone in a mass ratio of 2:1.

[0019] Preferably, the polymerization inhibitor described in step 2) is methylhydroquinone. Preferably, the polymerization inhibitor described in step 3) is hydroquinone.

[0020] The application of the unsaturated resin prepared by the preparation method is in the field of artificial stone for construction.

[0021] The technical solution of the present invention is described as follows:

[0022] Preferably, the 4,5,6-carbon dicarboxylic acid is a mixture composed of 20-22% by mass of adipic acid, 59-62% by mass of glutaric acid, and 18-20% by mass of succinic acid.

[0023] Further preferably, the 4,5,6-carbon dicarboxylic acid is a mixture composed of 20.7% by mass of adipic acid, 60.8% by mass of glutaric acid, and 18.5% by mass of succinic acid.

[0024] The 4, 5, and 6-carbon dicarboxylic acids are used in combination with adipic acid, glutaric acid, and succinic acid in this ratio. The chain extension is carried out with dibasic acids of three different alkane chain lengths to improve the toughness of the resin, ultimately improving the impact resistance of the obtained unsaturated resin, solving the problems of poor brittleness and poor impact strength in the application of artificial stone, and expanding the application range of the product. Among them, the alkane chain length of succinic acid is relatively short. If the dosage exceeds 25%, it will have an obvious adverse effect on the toughness of the resin. If the dosage of succinic acid is less than 17%, it will cause the hardness of the obtained resin to be too low, making the artificial stone too soft and losing the stone-like texture. A 17-25% addition ratio of succinic acid is a better addition ratio, and a further preferred 18-20% is the optimal ratio of succinic acid. The artificial stone made from the obtained resin has both good toughness and high hardness.

[0025] Step 1): Add the following parts by weight: 176-250 parts of saturated dibasic acid, 166.6-234 parts of diol, 0.05-0.071 parts of antioxidant, and 0.015-0.021 parts of inhibitor.

[0026] Step 2): Add the following parts by weight: 248.1-380.9 parts of the saturated polyester described in Step 1), 124-170 parts of saturated dibasic acid, 262-333 parts of unsaturated dibasic acid, 274.3-331 parts of diol, 0.48-1.11 parts of antioxidant, 0.16-0.28 parts of inhibitor, and 0.07-0.147 parts of paraffin.

[0027] Step 3): Add the following parts by weight: 340-357 parts of diluent, 0.032-0.071 parts of inhibitor, and 27.5-55.2 parts of saturated polyester.

[0028] In the unsaturated resin, the molar ratio of the unsaturated dibasic acid to the saturated dibasic acid is 1.1-1.2. The unsaturated dibasic acid is the unsaturated dibasic acid in Step 2); the saturated dibasic acid is the sum of the saturated dibasic acids in Step 1) and Step 2).

[0029] Compared with the prior art, the beneficial effects of the preparation method and application of an unsaturated resin for artificial stone of the present invention are:

[0030] 1. The unsaturated resin prepared by the preparation method of the present invention has high toughness, small shrinkage, and excellent curing effect.

[0031] First, C4-C6 dicarboxylic acids are introduced into the polyester as long-chain dicarboxylic acids. They are inexpensive and can reduce costs. At the same time, it is found that when the C4-C6 dicarboxylic acid is composed of 12-23% by mass of adipic acid, 53-63% of glutaric acid, and 17-25% of succinic acid, the prepared unsaturated resin has good toughness and impact resistance, and at the same time has high hardness and compatibility. When used in downstream processing, the artificial stone made from the unsaturated resin of the present invention can have a good stone-like texture both in terms of touch and usage experience.

[0032] Secondly, a long-chain saturated polyester is synthesized in step 1) to improve the wettability of the unsaturated resin to the filler. Then, maleic anhydride containing an unsaturated bond is connected in step 2), making the molecular chain of the resin relatively uniform, and at the same time the double-bond structure is relatively outside, which is easy to participate in subsequent cross-linking reactions, thereby improving the curing effect of the unsaturated resin.

[0033] Thirdly, a small amount of saturated polyester is added in step 3). Since the saturated polyester can be well dissolved in the diluent of the unsaturated resin and does not contain active double bonds and does not participate in cross-linking reactions, it can act as an anti-shrinkage agent, effectively reducing the curing shrinkage generated during the stone processing, avoiding cracking, making the surface of the cured artificial stone flat and shiny without ripples, and the obtained artificial stone is more suitable for making kitchen and bathroom countertops, window sill countertops, background walls, and column facings with high requirements for flatness and gloss.

[0034] 2. The unsaturated resin prepared by the preparation method of the present invention is suitable for the field of artificial stone for construction and is used as a binder for artificial stone. Detailed implementation mode

[0035] The following further details the present invention with specific examples, but the implementation of the present invention is not limited to this. Among them, Example 4 is the best example.

[0036] The C4-C6 dicarboxylic acid used in the examples is composed of 20.7% by mass of adipic acid, 60.8% by mass of glutaric acid, and 18.5% by mass of succinic acid.

[0037] The chemical formula of α-methylstyrene is C9H 10 , purchased from Merck Life Sciences.

[0038] The antioxidant used in step 1) and step 2) is triphenyl phosphite.

[0039] Table 1 Raw materials used in Examples 1-5 (by weight)

[0040] .

[0041] Examples 1-7

[0042] Preparation method of unsaturated resin for artificial stone, comprising the following steps:

[0043] 1) Saturated polyester synthesis stage: At room temperature of 25°C, add 4,5,6-carbon dicarboxylic acid, ethylene glycol, antioxidant and inhibitor into the reaction kettle, introduce nitrogen, start stirring, and gradually heat up at a rate of 15°C / h. When the temperature rises to 168°C, keep it warm for 30 minutes, and then heat up to 205°C at a rate of 15 - 25°C / h. React at 205°C until the acid value drops to 16 - 20mgKOH / g and the viscosity value is 2.6 - 3Pa·s, then cool down to obtain saturated polyester;

[0044] 2) Unsaturated polyester synthesis stage: At room temperature of 25°C, put the saturated polyester obtained in step 1), phthalic anhydride, maleic anhydride, diethylene glycol and antioxidant into the reaction kettle, introduce nitrogen, start stirring, and gradually heat up at a rate of 15°C / h. When the temperature rises to 170°C, keep it warm for 30 minutes, and then heat up to 205°C at a rate of 15 - 25°C / h. React at 205°C until the acid value drops to 24 - 32mgKOH / g and the viscosity value is 0.38 - 0.42Pa·s, then start to cool down. When the temperature drops to 180°C, add inhibitor and paraffin, and continue to cool down. When the temperature drops to 125°C, obtain unsaturated polyester;

[0045] 3) Dilution stage: Add diluent and inhibitor to the 125°C unsaturated polyester obtained in step 2), and then add the saturated polyester in step 1). Cool down and stir for 20 - 40 minutes to obtain unsaturated resin.

[0046] Example 6

[0047] The formula and preparation method of this example are the same as those of Example 4, the difference being that: in step 3), the diluent is a mixture of styrene and α-methylstyrene mixed by a mass ratio of 11:1. In this example, the amount of styrene is 311.6 parts and the amount of α-methylstyrene is 28.4 parts.

[0048] Example 7

[0049] The formula and preparation method of this example are the same as those of Example 4, the difference being that: in step 3), the diluent is a mixture of styrene and α-methylstyrene mixed by a mass ratio of 9.5:1. In this example, the amount of styrene is 307.7 parts and the amount of α-methylstyrene is 32.3 parts.

[0050] Comparative example

[0051] The comparative example is a comparative example designed to prove the technical effect of the present invention, and the specific differences are as follows.

[0052] Comparative example 1

[0053] This comparative example is the same as Example 4, except that: the C4-C6 dicarboxylic acid used in step 1) is replaced with phthalic anhydride of equal mass.

[0054] Comparative Example 2

[0055] This comparative example is the same as Example 4, except that: in step 3), no saturated polyester is added.

[0056] Comparative Example 3

[0057] This comparative example is the same as Example 4, except that: there is no operation in the saturated polyester synthesis stage of step 1), and only steps 2) and 3) are operated.

[0058] The saturated polyester used in step 2) and step 3) of this comparative example is replaced with: a mixture of 188 parts of C4-C6 dicarboxylic acid and 179 parts of oxalic acid. The composition of the C4-C6 dicarboxylic acid is the same as that in Example 4.

[0059] The purpose is to put the C4-C6 dicarboxylic acid and the unsaturated dibasic acid into the reaction kettle at the same time for one-step synthesis and polycondensation reaction to verify the performance of the obtained resin.

[0060] The C4-C6 dicarboxylic acid used in Comparative Examples 4, 5, and 6 is prepared by mixing commercially available adipic acid, glutaric acid, and succinic acid at room temperature according to mass percentage, aiming to verify the technical effect of the composition ratio of the C4-C6 dicarboxylic acid.

[0061] Comparative Example 4

[0062] This comparative example is the same as Example 4, except that: the amount of adipic acid is too small;

[0063] The C4-C6 dicarboxylic acid used in step 1) of this comparative example is a mixture composed of 9% by mass of adipic acid, 64% of glutaric acid, and 27% of succinic acid.

[0064] Comparative Example 5

[0065] This comparative example is the same as Example 4, except that: the amount of glutaric acid is too small;

[0066] The C4-C6 dicarboxylic acid used in step 1) of this comparative example is a mixture composed of 26% by mass of adipic acid, 45% of glutaric acid, and 29% of succinic acid.

[0067] Comparative Example 6

[0068] This comparative example is the same as Example 4, except that: the amount of succinic acid is too small;

[0069] The 4, 5, 6-carbon dicarboxylic acid used in step 1) of this comparative example is a mixture composed of 25% adipic acid, 64% glutaric acid, and 11% succinic acid by mass percentage.

[0070] Performance test

[0071] The unsaturated resins obtained in the examples and comparative examples were respectively subjected to performance tests, and the test results were respectively recorded in Table 2 and Table 3.

[0072] Sample preparation and performance tests were carried out according to standards GB / T24148, GB / T3854, GB / T2567, GB / T1634, and GB / T39818. The oil absorption value is effective data for detecting the wettability of the resin to the filler. 100 g of the resin and 200 g of 800-mesh calcium powder were dispersed evenly, and the viscosity test was carried out at a unified temperature. The lower the oil absorption value, the better the effect.

[0073] Table 2 Performance test results of the examples

[0074] 。

[0075] Table 3 Performance test results of the comparative examples

[0076] 。

[0077] It can be seen from Tables 2-3 that: in Comparative Example 1, 4, 5, 6-carbon dicarboxylic acid was not used. Compared with Comparative Example 1, the examples proved that the introduction of 4, 5, 6-carbon dicarboxylic acid significantly improved the toughness of the resin, and the elongation at break and impact strength increased significantly.

[0078] In Comparative Example 2, saturated polyester was not added in the dilution stage in step 3). Compared with Comparative Example 2, the examples proved that adding saturated polyester in the dilution stage reduced the curing shrinkage of the resin, improved the application performance of the resin, and made the surface of the prepared stone flat and shiny.

[0079] In Comparative Example 3, 4, 5, 6-carbon dicarboxylic acid and unsaturated dibasic acid were simultaneously put into the reaction kettle for one-step synthesis and polycondensation reaction. Compared with Comparative Example 3, the examples proved that: in the examples, long-chain saturated polyester was first synthesized in step 1), which significantly reduced the oil absorption value of the resin, improved the compatibility between the resin and the filler, shortened the curing time, and at the same time obtained good curing effects and excellent mechanical properties.

[0080] The ratio of the three acids in the C4-C6 dicarboxylic acids of Comparative Examples 4-6 is different from that of the Examples. The toughness and impact resistance of Comparative Examples 4 and 5 are inferior to those of the Examples. Comparative Example 6 becomes significantly softer and its hardness decreases. Comparative Examples 4-6 are not suitable for making artificial stone, which proves that if the amount of any one of the three acids is too small, the toughness and compatibility of the obtained unsaturated resin are not ideal. While using the ratio of C4-C6 dicarboxylic acids in the present invention can significantly improve the toughness and compatibility of the unsaturated resin, and at the same time has good hardness.

[0081] In Example 4, the mass ratio of styrene to α-methylstyrene is 10.33:1. The amount of diluent used in Example 4 is less than that in Examples 1, 2, 3 and 5, but the resin shrinkage rate is lower and the effect is better, which proves that styrene and α-methylstyrene have a synergistic effect.

[0082] In Examples 6-7, the mass ratio of styrene to α-methylstyrene in the diluent used is different from that in Example 4. It can be seen that although the shrinkage rates of Examples 6 and 7 are relatively good, they are lower than that of Example 4. The increase in the amount of α-methylstyrene in Example 7 affects the strength and hardness properties. Therefore, in Examples 6 and 7, the mass ratio of styrene to α-methylstyrene ranges from 9.5:1 to 11:1 as the end values, and Example 4 is the peak value. Within this range, mixing styrene and α-methylstyrene as the diluent has a better synergistic effect and can obtain a better curing effect, thereby reducing the shrinkage rate of the unsaturated resin of the present invention. Among them, the optimal ratio of the diluent is to mix styrene and α-methylstyrene at a mass ratio of 10.3-10.4:1.

[0083] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution content of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims

1. A preparation method of unsaturated resin for artificial stone, characterized in that, It includes the following steps: 1) Saturated polyester synthesis stage: From saturated dibasic acids, diols, antioxidants and inhibitors, under nitrogen protection, heat up and react to synthesize saturated polyester; 2) Unsaturated polyester synthesis stage: From the saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol, antioxidant, inhibitor and paraffin described in step 1), under nitrogen protection, react to synthesize unsaturated polyester; 3) Dilution stage: When the temperature of the unsaturated polyester obtained in step 2) is 122 - 128 °C, add diluent and inhibitor, then add the saturated polyester in step 1), cool down and stir for 20 - 40 minutes to obtain unsaturated resin; The saturated dibasic acid described in step 1) is a 4, 5, 6 - carbon dibasic acid, and the 4, 5, 6 - carbon dibasic acid is a mixture composed of 12 - 23% by mass of adipic acid, 53 - 63% of glutaric acid and 17 - 25% of succinic acid; The addition amount of the saturated polyester described in step 3) accounts for 2% - 4% by mass percentage of the total feeding amount in steps 2) and 3).

2. The preparation method of the unsaturated resin for artificial stone according to claim 1, characterized in that, The specific operation of step 1) is: Add saturated dibasic acid, diol, antioxidant and inhibitor into the reaction kettle, introduce nitrogen, start stirring, gradually heat up to 166 - 170 °C, keep warm for 20 - 40 minutes, then heat up to 202 - 208 °C at a speed of 15 - 25 °C / h, keep warm and react until the acid value drops to 16 - 20 mgKOH / g and the viscosity value is 2.6 - 3 Pa·s, then cool down to obtain saturated polyester.

3. The preparation method of the unsaturated resin for artificial stone according to claim 1, characterized in that, The specific operation of step 2) is: Put the saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol and antioxidant obtained in step 1) into the reaction kettle, introduce nitrogen, start stirring, gradually heat up to 167 - 173 °C, keep warm for 20 - 40 minutes, then heat up to 202 - 208 °C at a speed of 15 - 25 °C / h, keep warm and react until the acid value drops to 24 - 32 mgKOH / g and the viscosity value is 0.38 - 0.42 Pa·s, start to cool down, when it cools down to 177 - 183 °C, add inhibitor and paraffin, continue to cool down, when it cools down to 122 - 128 °C, obtain unsaturated polyester.

4. The preparation method of the unsaturated resin for artificial stone according to claim 1 or 2, characterized in that: The diol described in step 1) is ethylene glycol, and the antioxidant described in step 1) is triphenyl phosphite.

5. The preparation method of the unsaturated resin for artificial stone according to claim 1 or 3, characterized in that: The saturated dibasic acid described in step 2) is phthalic anhydride, the unsaturated dibasic acid described in step 2) is maleic anhydride, the diol described in step 2) is diethylene glycol; the antioxidant described in step 2) is triphenyl phosphite.

6. The preparation method of the unsaturated resin for artificial stone according to claim 1, characterized in that: The diluent described in step 3) is styrene, or a mixture of styrene and α - methylstyrene mixed in a mass ratio of 9.5 - 11:

1.

7. The preparation method of the unsaturated resin for artificial stone according to claim 1, 2 or 3, characterized in that: The inhibitor is at least one of hydroquinone, p - tert - butylcatechol, methylhydroquinone.

8. Use of the unsaturated resin prepared by the preparation method according to any one of claims 1 to 7, characterized in that: Application in the field of artificial building stones.