Preparation method and application of unsaturated resin for artificial stone

Abstract

The invention discloses a preparation method and application of unsaturated resin for artificial stone, and belongs to the technical field of unsaturated resin for buildings. Comprising the following steps: 1) heating saturated dibasic acid, dihydric alcohol, an antioxidant and a polymerization inhibitor under the protection of nitrogen, and reacting to synthesize saturated polyester; 2) reacting the saturated polyester in the step 1), saturated dibasic acid, unsaturated dibasic acid, dihydric alcohol, an antioxidant, a polymerization inhibitor and paraffin under the protection of nitrogen to synthesize saturated polyester; and (3) adding a diluent, a polymerization inhibitor and saturated polyester into the unsaturated polyester in the step (2), cooling and stirring to obtain the unsaturated resin for the artificial stone, the saturated dibasic acid in the step 1) is 4, 5, 6-carbon dicarboxylic acid and is formed by mixing 12-23% by mass of adipic acid, 53-63% by mass of glutaric acid and 17-25% by mass of succinic acid.The unsaturated resin prepared through the preparation method has the advantages of being high in toughness, small in shrinkage and excellent in curing effect and can be used as an adhesive of artificial stone for buildings.

Description

Technical Field

[0001] The invention discloses a preparation method and application of an unsaturated resin for artificial stone, belonging to the technical field of unsaturated resin for construction. Background Art

[0002] Artificial stone is made of unsaturated polyester resin as a binder, with powder filler, as well as an appropriate amount of coupling agent, flame retardant, and color. It is made by mixing ingredients, vibrating and compressing, and high-temperature curing. Depending on the usage scenario and process, the resin content in artificial marble is generally 22%-27% by mass, and the resin content in artificial quartz is 7%-13% by mass. The resin has a great influence on the performance and quality of artificial stone. During the resin curing transformation process, due to the increase in density and volume shrinkage, huge stress is generated inside the resin, which leads to cracking, warping, and uneven surface of the board. In order to pursue production speed, manufacturers hope that the resin will cure 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, which seriously affects the product quality and use effect of the product.

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

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

[0005] The technical solution adopted by the present invention to solve the technical problem is: the preparation method of the unsaturated resin for artificial stone comprises the following steps: 1) Saturated polyester synthesis stage: saturated dibasic acid, diol, antioxidant and inhibitor are heated and reacted to synthesize saturated polyester under nitrogen protection; 2) Unsaturated polyester synthesis stage: from step 1) saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol, antioxidant, polymerization inhibitor and paraffin, under nitrogen protection, unsaturated polyester is synthesized by reaction; 3) Dilution stage: add diluent, polymerization inhibitor and saturated polyester to the unsaturated polyester in step 2), cool and stir to obtain unsaturated resin; Step 1) The saturated dibasic acid is a 4,5,6 carbon dicarboxylic acid, which is a mixture of 12-23% by mass of adipic acid, 53-63% by mass of glutaric acid and 17-25% by mass of succinic acid.

[0006] The specific operation of step 1) is as follows: adding saturated dibasic acid, diol, antioxidant and polymerization inhibitor into a reaction kettle, introducing nitrogen, starting stirring, gradually heating to 166-170° C., keeping warm for 20-40 minutes, then heating to 202-208° C. at a rate of 15-25° C. / h, keeping warm for reaction until the acid value drops to 16-20 mgKOH / g and the viscosity value is 2.6-3 Pa·s, cooling to obtain saturated polyester.

[0007] The specific operation of step 2) is as follows: the saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol and antioxidant obtained in step 1) are put into a reaction kettle, nitrogen is introduced, stirring is started, the temperature is gradually increased to 167-173° C., and the temperature is kept at this temperature for 20-40 minutes, and then the temperature is increased to 202-208° C. at a rate of 15-25° C. / h, and the temperature is kept at this temperature for reaction until the acid value drops to 24-32 mgKOH / g and the viscosity value drops to 0.38-0.42 Pa·s, and the temperature is started to be lowered. When the temperature drops to 177-183° C., an inhibitor and paraffin are added, and the temperature is continued to be lowered to 122-128° C. to obtain an unsaturated polyester.

[0008] The specific operation of step 3) is: 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 and stir for 20-40 minutes, and obtain the unsaturated resin.

[0009] The diol in step 1) is ethylene glycol, and the antioxidant in step 1) is triphenyl phosphite.

[0010] 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.

[0011] Step 3) The diluent is styrene, or a mixture of styrene and α-methylstyrene at a mass ratio of 9.5-11:1. Preferably, the diluent in step 3) is a mixture of styrene and α-methylstyrene at a mass ratio of 10.3-10.4:1. α-methylstyrene has low reactivity, and a small amount of use can reduce the curing exotherm temperature, reduce shrinkage, and increase flexibility. 10.3-10.4:1 is the optimal ratio.

[0012] The amount of saturated polyester added in step 3) accounts for 2%-4% by weight of the total amount of materials added in step 2) and step 3). The total amount of materials added in step 2) and step 3) refers to the sum of the weight parts of the raw material addition amount in step 2) and the raw material addition amount in step 3). Adding saturated polyester in the dilution stage of step 3) can make up for the shrinkage of resin curing and reduce the shrinkage rate of resin, thereby improving 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 amount of unsaturated resin, it will have an adverse effect on the final curing effect of the resin and reduce the quality of the product; if it is less than 2% of the total amount of unsaturated resin, it will not play a role in reducing the shrinkage rate. Preferably, the saturated polyester in step 3) is the saturated polyester synthesized by the reaction in step 1).

[0013] The inhibitor in step 1), step 2) and step 3) is at least one of hydroquinone, p-tert-butylcatechol and methylhydroquinone.

[0014] Preferably, the polymerization inhibitor in step 1) is a mixture of hydroquinone and methyl hydroquinone in a mass ratio of 1.8-2.2:1. Further preferably, the polymerization inhibitor in step 1) is a mixture of hydroquinone and methyl hydroquinone in a mass ratio of 2:1.

[0015] Preferably, the polymerization inhibitor in step 2) is methyl hydroquinone. Preferably, the polymerization inhibitor in step 3) is hydroquinone.

[0016] The unsaturated resin prepared by the preparation method is applied in the field of artificial stone for construction.

[0017] The technical solution of the present invention is described as follows: Preferably, the 4,5,6-carbon dicarboxylic acid is a mixture of 20-22% by mass of adipic acid, 59-62% by mass of glutaric acid and 18-20% by mass of succinic acid.

[0018] More preferably, the 4,5,6-carbon dicarboxylic acid is a mixture of 20.7% by mass of adipic acid, 60.8% by mass of glutaric acid and 18.5% by mass of succinic acid.

[0019] 4,5,6 carbon dicarboxylic acids are used in combination with adipic acid, glutaric acid and succinic acid in this ratio. Three dibasic acids with different alkane chain lengths are used for chain extension to improve the toughness of the resin, and finally improve the impact resistance of the obtained unsaturated resin, solve the problems of poor brittleness and poor impact strength in the application of artificial stone, and expand the application of the product. Among them, the alkane chain length of succinic acid is relatively short. If the amount exceeds 25%, it will have a significant adverse effect on the toughness of the resin. If the amount of succinic acid is less than 17%, it will cause the hardness of the obtained resin to be too low, and the artificial stone made is too soft, and the artificial stone loses the imitation stone texture. 17-25% of succinic acid is a better addition ratio, and 18-20% is further preferred as the optimal ratio of succinic acid. The artificial stone made from the obtained resin has both good toughness and high hardness.

[0020] 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 polymerization inhibitor.

[0021] Step 2) Add the following parts by weight: 248.1-380.9 parts of the saturated polyester of 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.

[0022] 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.

[0023] The molar ratio of the unsaturated dibasic acid to the saturated dibasic acid in the unsaturated resin 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).

[0024] Compared with the prior art, the preparation method and application of an unsaturated resin for artificial stone of the present invention have the following beneficial effects: 1. The unsaturated resin prepared by the preparation method of the present invention has high toughness, small shrinkage and excellent curing effect.

[0025] First, 4,5,6 carbon dicarboxylic acid is introduced into polyester as a long-chain dibasic acid, which is cheap and can reduce costs. At the same time, it is found that when 4,5,6 carbon dicarboxylic acid is mixed with 12-23% by mass of adipic acid, 53-63% by mass of glutaric acid and 17-25% by mass of succinic acid, the obtained unsaturated resin has good toughness and impact resistance, and has high hardness and compatibility. During downstream processing, the artificial stone made by using the unsaturated resin of the present invention can have a good imitation stone texture in terms of touch and use experience.

[0026] Secondly, in step 1), a long-chain saturated polyester is synthesized to improve the wettability of the unsaturated resin to the filler, and then in step 2), maleic anhydride containing unsaturated bonds is connected to make the molecular chain of the resin more uniform and the double bond structure is relatively outward, which is easy to participate in the subsequent cross-linking reaction, thereby improving the curing effect of the unsaturated resin.

[0027] Again, in step 3), a small amount of saturated polyester is added. Since saturated polyester can be well dissolved in the diluent of unsaturated resin, does not contain active double bonds, and does not participate in cross-linking reaction, it can play the role of anti-shrinkage agent, effectively reducing the curing shrinkage produced in the stone processing process, avoiding cracking, and making the surface of artificial stone smooth and shiny after curing without ripples. The obtained artificial stone is more suitable for making kitchen and bathroom countertops, window sills, background walls and column veneers that have high requirements for flatness and gloss.

[0028] 2. The unsaturated resin prepared by the preparation method of the present invention is suitable for the field of artificial stone for construction as a binder for artificial stone. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with specific embodiments, but the implementation of the present invention is not limited thereto. Embodiment 4 is the best embodiment.

[0030] The 4,5,6-carbon dicarboxylic acid used in the example is a mixture of 20.7% by mass of adipic acid, 60.8% by mass of glutaric acid and 18.5% by mass of succinic acid.

[0031] The chemical formula of α-methylstyrene is C9H 10 , purchased from Merck Life Science.

[0032] The antioxidant used in step 1) and step 2) is triphenyl phosphite.

[0033] Table 1 Raw materials used in Examples 1-5 (by weight) .

[0034] Examples 1-7 The method for preparing unsaturated resin for artificial stone comprises the following steps: 1) Saturated polyester synthesis stage: at room temperature of 25°C, 4,5,6 carbon dicarboxylic acid, ethylene glycol, antioxidant and polymerization inhibitor were added to the reactor, nitrogen was introduced, stirring was started, and the temperature was gradually increased at a rate of 15°C / h to 168°C, and kept warm for 30 minutes, and then the temperature was increased to 205°C at a rate of 15-25°C / h, and kept warm at 205°C for reaction until the acid value dropped to 16-20 mgKOH / g and the viscosity value was 2.6-3 Pa·s, and the temperature was lowered to obtain saturated polyester; 2) Unsaturated polyester synthesis stage: at room temperature of 25°C, the saturated polyester obtained in step 1), phthalic anhydride, maleic anhydride, diethylene glycol and antioxidant are placed in a reaction kettle, nitrogen is introduced, stirring is started, and the temperature is gradually increased at a rate of 15°C / h to 170°C, and the temperature is kept at this temperature for 30 minutes. The temperature is then increased at a rate of 15-25°C / h to 205°C, and the temperature is kept at this temperature for reaction until the acid value drops to 24-32 mgKOH / g and the viscosity value drops to 0.38-0.42 Pa·s. The temperature is then lowered, and when the temperature drops to 180°C, an inhibitor and paraffin are added. The temperature is then continued to be lowered to 125°C to obtain an unsaturated polyester. 3) Dilution stage: Add diluent and polymerization inhibitor to the unsaturated polyester at 125°C obtained in step 2), then add the saturated polyester in step 1), cool and stir for 20-40 minutes to obtain the unsaturated resin.

[0035] Example 6 The formula and preparation method of this embodiment are the same as those of embodiment 4, except that: the diluent in step 3) is a mixture of styrene and α-methylstyrene in a mass ratio of 11:1. In this embodiment, styrene is 311.6 parts and α-methylstyrene is 28.4 parts.

[0036] Example 7 The formula and preparation method of this embodiment are the same as those of embodiment 4, except that: the diluent in step 3) is a mixture of styrene and α-methylstyrene in a mass ratio of 9.5:1. In this embodiment, styrene is 307.7 parts and α-methylstyrene is 32.3 parts.

[0037] Comparative Example The comparative examples are designed to demonstrate the technical effects of the present invention, and the specific differences are as follows.

[0038] Comparative Example 1 This comparative example is the same as Example 4, except that the 4,5,6 carbonyl dicarboxylic acid used in step 1) is replaced by an equal mass of phthalic anhydride.

[0039] Comparative Example 2 This comparative example is the same as Example 4, except that no saturated polyester is added in step 3).

[0040] Comparative Example 3 This comparative example is the same as Example 4, except that step 1) the saturated polyester synthesis stage is not performed, and only steps 2) and 3) are performed.

[0041] The saturated polyester used in step 2) and step 3) of this comparative example is replaced by a mixture of 188 parts of 4,5,6 carbon dicarboxylic acid and 179 parts of oxalic acid. The composition of the 4,5,6 carbon dicarboxylic acid is the same as that of Example 4.

[0042] The purpose is to put 4,5,6 carbon dicarboxylic acids and unsaturated dibasic acids into a reactor at the same time for a one-step synthetic polycondensation reaction and verify the performance of the resulting resin.

[0043] The 4,5,6 carbon dicarboxylic acids used in Comparative Examples 4, 5 and 6 are prepared by mixing commercially available adipic acid, glutaric acid and succinic acid according to mass percentage at room temperature, in order to verify the technical effect of the composition ratio of the 4,5,6 carbon dicarboxylic acids.

[0044] Comparative Example 4 This comparative example is the same as Example 4, except that: there is too little adipic acid; The 4,5,6-carbon dicarboxylic acid used in step 1) of this comparative example is a mixture of 9% by mass of adipic acid, 64% by mass of glutaric acid and 27% by mass of succinic acid.

[0045] Comparative Example 5 This comparative example is the same as Example 4, except that: there is too little glutaric acid; The 4,5,6-carbon dicarboxylic acid used in step 1) of this comparative example is a mixture of 26% by mass of adipic acid, 45% by mass of glutaric acid and 29% by mass of succinic acid.

[0046] Comparative Example 6 This comparative example is the same as Example 4, except that: there is too little succinic acid; The 4,5,6-carbon dicarboxylic acid used in step 1) of this comparative example is a mixture of 25% by mass of adipic acid, 64% by mass of glutaric acid and 11% by mass of succinic acid.

[0047] Performance Testing The unsaturated resins obtained in the examples and comparative examples were tested for performance, and the test results are recorded in Tables 2 and 3, respectively.

[0048] Sample preparation and performance testing are carried out according to standards GB / T24148, GB / T3854, GB / T2567, GB / T1634, and GB / T39818. Oil absorption value is an effective data for testing the wettability of resin to fillers. 100g of resin and 200g of 800 mesh calcium powder are evenly dispersed and the viscosity test is carried out at a uniform temperature. The lower the oil absorption value, the better the effect.

[0049] Table 2 Performance test results of the embodiment .

[0050] Table 3 Comparative Example Performance Test Results .

[0051] It can be seen from Table 2-3 that Comparative Example 1 does not use 4,5,6 carbon dicarboxylic acid. Compared with Comparative Example 1, the examples prove that the introduction of 4,5,6 carbon dicarboxylic acid significantly improves the toughness of the resin, and significantly increases the elongation at break and the impact strength.

[0052] Comparative Example 2 did not add saturated polyester in the dilution stage of step 3). Compared with Comparative Example 2, the addition of saturated polyester in the dilution stage reduces the curing shrinkage of the resin, improves the application performance of the resin, and makes the surface of the obtained stone smooth and glossy.

[0053] In comparative example 3, 4, 5, 6 carbon dicarboxylic acids and unsaturated dibasic acids are simultaneously put into a reactor for a one-step synthesis polycondensation reaction. Compared with comparative example 3, the embodiment proves that: the embodiment adopts the method of synthesizing long-chain saturated polyester in step 1), which significantly reduces the oil absorption value of the resin, improves the compatibility of the resin and the filler, shortens the curing time, and obtains a good curing effect, and has excellent mechanical properties.

[0054] The ratio of the three acids in the 4,5,6 carbon dicarboxylic acid of Comparative Examples 4-6 is different from that of the embodiment. The toughness and impact resistance of Comparative Examples 4 and 5 are not as good as those of the embodiment. Comparative Example 6 is obviously softened and the hardness decreases. Comparative Examples 4-6 are not suitable for making artificial stone, which proves that if any one of the three acids is used in too little amount, the toughness and compatibility of the obtained unsaturated resin are not ideal. The ratio of the 4,5,6 carbon dicarboxylic acid in the present invention can significantly improve the toughness and compatibility of the unsaturated resin, and at the same time, the hardness is better.

[0055] The mass ratio of styrene to α-methylstyrene in Example 4 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.

[0056] The mass ratio of styrene to α-methylstyrene in the diluent used in Examples 6-7 is different from that in Example 4. It can be seen that although the shrinkage rates of Examples 6 and 7 are better, they are lower than that of Example 4. The increased amount of α-methylstyrene in Example 7 affects the performance of strength and hardness. Therefore, the mass ratios of styrene to α-methylstyrene in Examples 6 and 7 are 9.5:1 and 11:1 as end values, and Example 4 is the peak value. Within this range, styrene and α-methylstyrene are mixed as diluents, which has a good synergistic effect and can obtain a good curing effect, thereby reducing the shrinkage rate of the unsaturated resin of the present invention. Among them, the optimal ratio of the diluent is that styrene and α-methylstyrene are mixed at a mass ratio of 10.3-10.4:1.

[0057] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing an unsaturated resin for artificial stone, characterized in that: The following steps are involved: 1) Saturated polyester synthesis stage: saturated dibasic acid, diol, antioxidant and inhibitor are heated and reacted to synthesize saturated polyester under nitrogen protection; 2) Unsaturated polyester synthesis stage: the saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol, antioxidant, polymerization inhibitor and paraffin described in step 1) are reacted under nitrogen protection to synthesize unsaturated polyester; 3) Dilution stage: add diluent, polymerization inhibitor and saturated polyester to the unsaturated polyester in step 2), cool and stir to obtain unsaturated resin; Step 1) The saturated dibasic acid is a 4,5,6 carbon dicarboxylic acid, which is a mixture of 12-23% by mass of adipic acid, 53-63% by mass of glutaric acid and 17-25% by mass of succinic acid.

2. The method for preparing an unsaturated resin for artificial stone according to claim 1, characterized in that: The specific operation of step 1) is as follows: adding saturated dibasic acid, diol, antioxidant and polymerization inhibitor into a reaction kettle, introducing nitrogen, starting stirring, gradually heating to 166-170° C., keeping warm for 20-40 minutes, then heating to 202-208° C. at a rate of 15-25° C. / h, keeping warm for reaction until the acid value drops to 16-20 mgKOH / g and the viscosity value is 2.6-3 Pa·s, cooling to obtain saturated polyester.

3. The method for preparing an unsaturated resin for artificial stone according to claim 1, characterized in that: The specific operation of step 2) is as follows: the saturated polyester, saturated dibasic acid, unsaturated dibasic acid, diol and antioxidant obtained in step 1) are put into a reaction kettle, nitrogen is introduced, stirring is started, the temperature is gradually increased to 167-173° C., and the temperature is kept at this temperature for 20-40 minutes, and then the temperature is increased to 202-208° C. at a rate of 15-25° C. / h, and the temperature is kept at this temperature for reaction until the acid value drops to 24-32 mgKOH / g and the viscosity value drops to 0.38-0.42 Pa·s, and the temperature is started to be lowered. When the temperature drops to 177-183° C., an inhibitor and paraffin are added, and the temperature is continued to be lowered to 122-128° C. to obtain an unsaturated polyester.

4. The method for preparing an unsaturated resin for artificial stone according to claim 1, characterized in that: The specific operation of step 3) is: 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 and stir for 20-40 minutes, and obtain the unsaturated resin.

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

6. The method for preparing an unsaturated resin for artificial stone according to claim 1 or 3, characterized in that: 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.

7. The method for preparing an unsaturated resin for artificial stone according to claim 1 or 4, characterized in that: Step 3) The diluent is styrene, or a mixture of styrene and α-methylstyrene in a mass ratio of 9.5-11:

1.

8. The method for preparing an unsaturated resin for artificial stone according to claim 1 or 4, characterized in that: The amount of saturated polyester added in step 3) accounts for 2%-4% by mass of the total amount of materials added in step 2) and step 3).

9. The method for preparing an unsaturated resin for artificial stone according to claim 1, 2, 3 or 4, characterized in that: The polymerization inhibitor is at least one of hydroquinone, p-tert-butylcatechol and methylhydroquinone.

10. Application of the unsaturated resin prepared by the preparation method according to any one of claims 1 to 9, characterized in that: Application in the field of artificial stone for construction.